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Stacking Winegard HD-6065P antennas
"Jeff Liebermann" wrote in message ... This is more fun: http://802.11junk.com/jeffl/antennas/connector-loss/index.html Just take every connector that you can find, put them in series, and measure the loss. In this case, it was done at 2.4Ghz and 450MHz. End to end loss at 2.4GHz was 2dB for about 25 adapters or about 0.08dB per adapter. At 250MHz, the loss was about 0.2dB or 0.008dB per adapter. I've done similar demonstrations using two wattmeters at the local radio club meeting. The results are typically that the adapter string has the same loss as an equivalent length of small coax cable. I had I have done something similar. Hook all the adaptors I could find to my hp 8924c and sweep from 30 to 1000 mhz (limit of the equipment). Not much loss at all. Best demonstration is to apply power. Even at 1 db of loss and running 1 kw you would have over 100 watts of heat. Enough to burn your hand in a few seconds. The only way I have seen demonstrared is when the connectors creat an impedance bump and it may take a couple of them in series so the effects multiply much greater than just adding the losses. They may have to be a certain ammount of wavelength apart for this to hapen. The effect is that you have a long piece of coax with a very high SWR. --- This email is free from viruses and malware because avast! Antivirus protection is active. http://www.avast.com |
Stacking Winegard HD-6065P antennas
On 1/10/2014 10:23 PM, Ralph Mowery wrote:
"Jeff Liebermann" wrote in message ... On Fri, 10 Jan 2014 19:36:59 -0500, Jerry Stuckle Actually, it's not the crimp job that kills the connection. It's the stripping of the coax that causes the most problems. I use various rotary contrivances that have razor blades to make the cuts at the correct spacing. Those work well initially, but after about 50 connectors, the blades become dull and useless. Of course, nobody has spare blades or knows how to adjust them. They either continue to use a dull razor or steal my new stripper. I don't know the quality of the cutters you use, but I have bought several from China off ebay for about $ 2 each including shipping. For the very few connectors I do, they work. At that price, you could order a lot of them and not worry about the replacement blades. Just like the disposiable razors. They seem identical to the ones that sell in stores for $ 10 to $ 15 . Ralph, They may seem identical, but they aren't. The $10-15 ones last much, much longer. However, unless you're doing it full time, it probably doesn't pay to get the more expensive ones. We tried one of the cheap ones. After about 3 weeks the tech threw it as far as he could because he was so frustrated. The ones we have now typically last a year or more (we don't really track them). -- ================== Remove the "x" from my email address Jerry, AI0K ================== |
Stacking Winegard HD-6065P antennas
On Fri, 10 Jan 2014 22:23:17 -0500, "Ralph Mowery"
wrote: "Jeff Liebermann" wrote in message .. . On Fri, 10 Jan 2014 19:36:59 -0500, Jerry Stuckle Actually, it's not the crimp job that kills the connection. It's the stripping of the coax that causes the most problems. I use various rotary contrivances that have razor blades to make the cuts at the correct spacing. Those work well initially, but after about 50 connectors, the blades become dull and useless. Of course, nobody has spare blades or knows how to adjust them. They either continue to use a dull razor or steal my new stripper. I don't know the quality of the cutters you use, but I have bought several from China off ebay for about $ 2 each including shipping. For the very few connectors I do, they work. At that price, you could order a lot of them and not worry about the replacement blades. Just like the disposiable razors. They seem identical to the ones that sell in stores for $ 10 to $ 15 . Those are the same cutters that I like to use. Good, cheap, easy to use, and throw away when dull. (I've tried resharpening the blades with poor results). This style is my favorite: http://www.ebay.com/itm/400525856013 but these also work and are usually cheaper: http://www.ebay.com/itm/360806269903 There are other designs, but I haven't used them. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
Stacking Winegard HD-6065P antennas
On Fri, 10 Jan 2014 18:06:54 -0800, Jeff Liebermann
wrote: (...) Actually, it's not the crimp job that kills the connection. It's the stripping of the coax that causes the most problems. I use various rotary contrivances that have razor blades to make the cuts at the correct spacing. Those work well initially, but after about 50 connectors, the blades become dull and useless. Of course, nobody has spare blades or knows how to adjust them. They either continue to use a dull razor or steal my new stripper. Oops... dinner... gone. The problem with the dull cutter usually creates problems where the dielectric ends, and where the solid center conductor is exposed. The dull blade pushes the aluminum shield over the end of the dielectric, shorting the aluminum or the braid wire to the center conductor. Even if it doesn't immediately short, some movement of the cable can cause it to short. When it gets to this point, I have to take a sharp knife and cut back the shielding so that it won't short. However, once the connector is pushed in place, it can't be checked or repaired. I can offer several other ways to do it wrong, but that should suffice for now. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
Stacking Winegard HD-6065P antennas
On 1/10/2014 11:13 PM, Jeff Liebermann wrote:
On Fri, 10 Jan 2014 18:06:54 -0800, Jeff Liebermann wrote: (...) Actually, it's not the crimp job that kills the connection. It's the stripping of the coax that causes the most problems. I use various rotary contrivances that have razor blades to make the cuts at the correct spacing. Those work well initially, but after about 50 connectors, the blades become dull and useless. Of course, nobody has spare blades or knows how to adjust them. They either continue to use a dull razor or steal my new stripper. Oops... dinner... gone. The problem with the dull cutter usually creates problems where the dielectric ends, and where the solid center conductor is exposed. The dull blade pushes the aluminum shield over the end of the dielectric, shorting the aluminum or the braid wire to the center conductor. Even if it doesn't immediately short, some movement of the cable can cause it to short. When it gets to this point, I have to take a sharp knife and cut back the shielding so that it won't short. However, once the connector is pushed in place, it can't be checked or repaired. I can offer several other ways to do it wrong, but that should suffice for now. We don't let them get even close to that dullness. Our techs can tell when they're starting to get dull and replace them because problems will start much before when the shield pushes the shield over. For instance, the inner dielectric will distort, making it harder to install the connector. -- ================== Remove the "x" from my email address Jerry, AI0K ================== |
Stacking Winegard HD-6065P antennas
"Jerry Stuckle" wrote in message ... , They may seem identical, but they aren't. The $10-15 ones last much, much longer. However, unless you're doing it full time, it probably doesn't pay to get the more expensive ones. We tried one of the cheap ones. After about 3 weeks the tech threw it as far as he could because he was so frustrated. The ones we have now typically last a year or more (we don't really track them). You probably do more connectors in a week than I will ever do. For me , it won't pay, but for you it will if they last that much longer. Must be the quality of the blades as I can not tell any differance in the couple I bought from China for $ 2 and the one I bought here for $ 15. I just bought one for each size and type of cable I use. I don't do the TV connectors, just the BNC,N,PL259 types. --- This email is free from viruses and malware because avast! Antivirus protection is active. http://www.avast.com |
Stacking Winegard HD-6065P antennas
In message , Jerry Stuckle
writes The best (and the ones we use) compress the entire base of the connector evenly, creating a smooth crimp. The end of the coax is evenly covered by the connector. In the CATV industry, for F-connectors, isn't Snap-n-Seal now de the norm? -- Ian |
Stacking Winegard HD-6065P antennas
On 1/10/2014 11:39 PM, Ralph Mowery wrote:
"Jerry Stuckle" wrote in message ... , They may seem identical, but they aren't. The $10-15 ones last much, much longer. However, unless you're doing it full time, it probably doesn't pay to get the more expensive ones. We tried one of the cheap ones. After about 3 weeks the tech threw it as far as he could because he was so frustrated. The ones we have now typically last a year or more (we don't really track them). You probably do more connectors in a week than I will ever do. For me , it won't pay, but for you it will if they last that much longer. Must be the quality of the blades as I can not tell any differance in the couple I bought from China for $ 2 and the one I bought here for $ 15. I just bought one for each size and type of cable I use. I don't do the TV connectors, just the BNC,N,PL259 types. Yup, one tech can do upwards of 50 connectors a day on a large project. Mostly F and RJ-45, but also some RCA and others. It counts up quickly! :) -- ================== Remove the "x" from my email address Jerry, AI0K ================== |
Stacking Winegard HD-6065P antennas
On 1/11/2014 5:24 AM, Jeff wrote:
As for handling more power - rubbish. The current in 75 ohm coax is lower than that in 50 ohm coax, for the same power rating. Can you not see the stupidity if that remark??? Jeff It is perfectly true. P=I^2xR. As R increases, I MUST decrease to handle the same power. And since current is the limiting factor in wire, you don't need as large a gauge of wire to handle more power. You really should learn what you're talking about before opening your "mouth". You only continue to show your ignorance. -- ================== Remove the "x" from my email address Jerry, AI0K ================== |
Stacking Winegard HD-6065P antennas
On 1/11/2014 3:44 AM, Ian Jackson wrote:
In message , Jerry Stuckle writes The best (and the ones we use) compress the entire base of the connector evenly, creating a smooth crimp. The end of the coax is evenly covered by the connector. In the CATV industry, for F-connectors, isn't Snap-n-Seal now de the norm? Maybe for cable companies who are trying to be cheap. But the professional integrators around here all use crimp-on. Not much more expensive and saving one callback pays for a lot of connectors. -- ================== Remove the "x" from my email address Jerry, AI0K ================== |
Stacking Winegard HD-6065P antennas
In message , Jerry Stuckle
writes On 1/11/2014 3:44 AM, Ian Jackson wrote: In message , Jerry Stuckle writes The best (and the ones we use) compress the entire base of the connector evenly, creating a smooth crimp. The end of the coax is evenly covered by the connector. In the CATV industry, for F-connectors, isn't Snap-n-Seal now de the norm? Maybe for cable companies who are trying to be cheap. But the professional integrators around here all use crimp-on. Not much more expensive and saving one callback pays for a lot of connectors. Snap-n-Seal certainly isn't trying to be cheap. https://www.google.co.uk/#q=snap+and+seal They enable an essentially watertight seal to be obtained without distorting (or even scratching) the connector, and therefore have little measurable effect on the impedance. -- Ian |
Stacking Winegard HD-6065P antennas
On 1/11/2014 10:25 AM, Ian Jackson wrote:
In message , Jerry Stuckle writes On 1/11/2014 3:44 AM, Ian Jackson wrote: In message , Jerry Stuckle writes The best (and the ones we use) compress the entire base of the connector evenly, creating a smooth crimp. The end of the coax is evenly covered by the connector. In the CATV industry, for F-connectors, isn't Snap-n-Seal now de the norm? Maybe for cable companies who are trying to be cheap. But the professional integrators around here all use crimp-on. Not much more expensive and saving one callback pays for a lot of connectors. Snap-n-Seal certainly isn't trying to be cheap. https://www.google.co.uk/#q=snap+and+seal They enable an essentially watertight seal to be obtained without distorting (or even scratching) the connector, and therefore have little measurable effect on the impedance. That's their claim, anyway. As I said - none of the professional integrators around here use it. The distributors don't even carry it. -- ================== Remove the "x" from my email address Jerry Stuckle JDS Computer Training Corp. ================== |
Stacking Winegard HD-6065P antennas
In message , Jerry Stuckle
writes On 1/11/2014 10:25 AM, Ian Jackson wrote: In message , Jerry Stuckle writes On 1/11/2014 3:44 AM, Ian Jackson wrote: In message , Jerry Stuckle writes The best (and the ones we use) compress the entire base of the connector evenly, creating a smooth crimp. The end of the coax is evenly covered by the connector. In the CATV industry, for F-connectors, isn't Snap-n-Seal now de the norm? Maybe for cable companies who are trying to be cheap. But the professional integrators around here all use crimp-on. Not much more expensive and saving one callback pays for a lot of connectors. Snap-n-Seal certainly isn't trying to be cheap. https://www.google.co.uk/#q=snap+and+seal They enable an essentially watertight seal to be obtained without distorting (or even scratching) the connector, and therefore have little measurable effect on the impedance. That's their claim, anyway. And they are true! As I said - none of the professional integrators around here use it "Professional integrators" covers a multitude of sins. Professional in what field? . The distributors don't even carry it. I suppose it depends which distributors you use. Such connectors are hardly unknown in the USA. www.tnb.com/pubint/docs/snapnseal.pdf In the UK cable TV industry, for most applications, it would be a hanging offence not to use an approved Snap-N-Seal connector. -- Ian |
Stacking Winegard HD-6065P antennas
On 1/11/2014 11:08 AM, Ian Jackson wrote:
In message , Jerry Stuckle writes On 1/11/2014 10:25 AM, Ian Jackson wrote: In message , Jerry Stuckle writes On 1/11/2014 3:44 AM, Ian Jackson wrote: In message , Jerry Stuckle writes The best (and the ones we use) compress the entire base of the connector evenly, creating a smooth crimp. The end of the coax is evenly covered by the connector. In the CATV industry, for F-connectors, isn't Snap-n-Seal now de the norm? Maybe for cable companies who are trying to be cheap. But the professional integrators around here all use crimp-on. Not much more expensive and saving one callback pays for a lot of connectors. Snap-n-Seal certainly isn't trying to be cheap. https://www.google.co.uk/#q=snap+and+seal They enable an essentially watertight seal to be obtained without distorting (or even scratching) the connector, and therefore have little measurable effect on the impedance. That's their claim, anyway. And they are true! That is their claim, anyway. As I said - none of the professional integrators around here use it "Professional integrators" covers a multitude of sins. Professional in what field? No, there is only one field of "Professional Integration". It covers everything from CCTV to security to automation systems to theaters (home and commercial). Residential, commercial, and anything in between. . The distributors don't even carry it. I suppose it depends which distributors you use. Such connectors are hardly unknown in the USA. www.tnb.com/pubint/docs/snapnseal.pdf In the UK cable TV industry, for most applications, it would be a hanging offence not to use an approved Snap-N-Seal connector. I didn't say they were unknown. Just that professional integrators (including us) use better quality connectors. And BTW, I checked with a couple of other integrator friends today. They've never seen the cable companies around here use them, either. In fact, the only place they've seen them used is by hobbyists and other consumers. No professionals. -- ================== Remove the "x" from my email address Jerry Stuckle ================== |
Stacking Winegard HD-6065P antennas
On 1/11/2014 11:33 AM, Jeff wrote:
On 11/01/2014 14:12, Jerry Stuckle wrote: On 1/11/2014 5:24 AM, Jeff wrote: As for handling more power - rubbish. The current in 75 ohm coax is lower than that in 50 ohm coax, for the same power rating. Can you not see the stupidity if that remark??? Jeff It is perfectly true. P=I^2xR. As R increases, I MUST decrease to handle the same power. And since current is the limiting factor in wire, you don't need as large a gauge of wire to handle more power. You really should learn what you're talking about before opening your "mouth". You only continue to show your ignorance. Perhaps you should actually look at the theory of coax transmission lines. If you did you would find that the optimum impedance for max power handling peaks at about 30 ohms and falls away either side of that impedance, 50 ohms being better than 75 ohms. It is a little more complicated than just Ohms Law. It would appear that it is you who are showing their ignorance, and inability to even look at the article that was linked in post that you were replying to!!! http://www.belden.com/blog/broadcastav/50-Ohms-The-Forgotten-Impedance.cfm Jeff Try again. I had it back in college in the early 70's (as an EE major), and I don't think the laws of physics have changed. And the best impedance for a coax is that which matches the input and output impedance of the system, or if the input and output are of different impedances, acts as a matching stub between the two. And yes, I read the article. But you obviously don't understand it. The 30 ohms they are talking about was for ONE SPECIFIC REQUIREMENT. That does NOT mean it is true in different situations. I suggest you learn what you're talking about before you make yourself look even sillier. - ================== Remove the "x" from my email address Jerry, AI0K ================== |
Stacking Winegard HD-6065P antennas
On Sat, 11 Jan 2014 19:41:20 -0500, Jerry Stuckle
wrote: I didn't say they were unknown. Just that professional integrators (including us) use better quality connectors. Could I trouble you for a photo or part number for the crimp type F connectors that you are using? I want to see what I'm missing. Incidentally, SCTE IPS-TP-401 specifies that F connectors should survive a 40 lb pull test. http://www.sbcatest.com/SBCA%20connector%20recommended%20practices.pdf I once built a fixture for testing this. Many of the cheap connectors that I randomly purchased on eBay failed the test. You might want to try it with your crimp connectors. And BTW, I checked with a couple of other integrator friends today. They've never seen the cable companies around here use them, either. In fact, the only place they've seen them used is by hobbyists and other consumers. No professionals. Once a year, CED Magazine[1] provides an F-connector cross reference wall chart. Here's the one for 2011. I don't recall seeing one in the past 2 years probably because the incompatibility problems have finally stabilized: http://www.cedmagazine.com/wallcharts/2011/10/f-connector-cross-reference-chart-2011 http://www.cedmagazine.com/sites/cedmagazine.com/files/Wall_Charts/1111_F-Cconnector-WC.pdf If you inspect the chart, you'll see the various SNS Snap-n-Seal part numbers. The advertisement in the lower right is for Belden/T&B SNS connectors. What I guess(tm) happened was prior to Belden purchasing Thomas and Betts in 2010, T&B had no interest in producing a connector that would work with all RG-6/u type cables. Having many different types means everyone has to carry a larger inventory. I'm too lazy to check, but my bin contains at least 4 different F plugs for various manufacturers cables and shield types of RG-6/u. I use the above chart to make sure I don't create a mismatch. The most common connector is the SNS1P6 LRC series, color coded "blue", which fits double shielded RG-6/u. http://www.tnb.com/pubint/docs/snapnseal.pdf (11 MBytes) http://www.youtube.com/watch?v=wBZAHhH4wCo (2 min) Immediately after the acquisition, Belden introduced the "red" connector, which is a universal replacement for most of the others and will fit double, triple, and quad shielded RG-6/u. My experience with this connector hase been quite good. However, I continue to use the "blue" for double shielded RG-6/u because I have about a years inventory of connectors left. When I reorder, it will probably be the universal (or ultimate) "red" type in cool looking nickel-tin plating. Locally, Comcast and Charter both use various types of T&B Snap-and-Seal connectors. I had Comcast install cable internet in our office building. That's all that I saw in use. In older installations, they use Augat LRC connectors, which are the predecessor of the current Belden/T&B connectors. You also mentioned compression and stripping tools. I have about 5 of them, ranging from cheap eBay junk to the T&B IT1000 which sells for about $100: http://www.mjsales.net/itemsearch.asp?FamilyID=202 The IT1000 seems to work best, although some odd extra long compression connectors, or the BNC or Phono compression connectors, require a different tool. I also stupidly bought a compression tool that only fits one manufacturers connectors, and none other. Most of my ham antennas use a compression BNC connector and/or F-connector to UHF or BNC adapter. My IT1000 is marked Augat LRC, which should give a clue as to its age. You also mentioned that you're using RG-59/u. Please note that RG-59/u lacks the foil shield(s) of RG-6/u which means that it leaks more and suffers from possible ingres problems. RG-59/u has higher attenuation: RG-59 RG-6 50 MHz 2.4 dB 1.5 dB 100 MHz 3.4 dB 2.0 dB 400 MHz 7.0 dB 4.3 dB 900 MHz 11.1 dB 6.8 dB 1000 MHz 12.0 dB 7.0 dB I've purged RG-59/u from my life many years ago. Are you sure you want to continue using the stuff. Not all RG-6/u cables are equal. Here's some junk: http://sewelldirect.com/RG6-Bulk-Cable-Black-60-Braided-1000ft-Spool.asp RG-6/u with no foil shield and only 60% coverage. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
Stacking Winegard HD-6065P antennas
On Fri, 10 Jan 2014 22:55:41 -0500, Jerry Stuckle
wrote: That's theoretical. Reality is much different. I think I'll print that on a large piece of paper and have it framed for my office wall. Have you ever worked with a TDR? It's one of the tools we use regularly (and an expensive one, also). Sure. Also OTDR for fiber. I don't use the expensive stuff, unless you include the Acterna HST3000 tester that was stolen from my office a few years ago. Mostly, I built my own using a pulse generator and an oscilloscope. You stated that the losses come primarily from the "impedance bump" presumably produced by the non-50 ohm connector or adapter in the line. Well, time to put that to the test. 1. Take a length of RG-6/u coax with good connectors. Apply signal on one end from a generator. Measure the signal level on the other end with a spectrum analyzer that has a 1dB per division scale. I want to be able to see small changes. 2. After establishing a reference level, either beat on the coax cable with a hammer, squash it with a C-clamp, or flatten it with a bench vise. Squash it just enough to obtain an "impedance bump", but not a short between the center conductor and shield. Note the change in level, if you can see it. 3. Now, either un-squash the cable, or find another length of RG-6/u and attach a TDR. It can be open, shorted, or terminated. Doesn't matter. 4. Flatten the cable in the same manner as before and note the TDR display. What I expect that you'll see is that there will be almost no change in attenuation, while the TDR display will show a rather radical "impedance bump". That's because the only thing that the change in impedance along the cable length can do is create reflections. Those are a serious problem in a CATV system, but really don't involve serious signal level losses. That's theoretical. Reality is much the same. So? Dipoles aren't 50 ohm antennas. They're typically closer to 75 ohm. I guess you missed my point. If you can tolerate the 1.5:1 VSWR, the reduced attenuation and cost of 75 ohm coax makes the effort worthwhile. As for handling more power - rubbish. The current in 75 ohm coax is lower than that in 50 ohm coax, for the same power rating. Please re-read the article: www.belden.com/blog/broadcastav/50-Ohms-The-Forgotten-Impedance.cfm http://www.microwaves101.com/encyclopedia/why50ohms.cfm We use RG-59 where appropriate, like from an outlet to the set top box. But our in-wall coax runs are all RG-6 quad-shielded. RG-59/u doesn't have a foil shield, so it's more flexible. So, I guess that might work. For short lengths, the increased leakage, higher ingress, and higher attenuation can probably be tolerated. However, I use extra long RG-6/u, which somewhat compensates for the lack of flexibility. But we're also doing less and less coax and more and more Category cable nowadays. No MoCA installations? http://www.mocalliance.org They're OK for the hobbyist, but I don't know of any professionals who use them. In fact, checking our main wholesalers, they aren't even available through them (but other Beldon products are). Find a different distributor or ask for it by part number. Thomas and Betts SNS1P6U. Quick check: Stocked by Allied, Newark, Tessco, Farnel(UK), MCM. Not stocked by Digikey, Mouser, Arrow. T&B distributor search: http://www.tnb.com/ps/dls/dls?ca=corp -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
Stacking Winegard HD-6065P antennas
On 1/11/2014 11:51 PM, Jeff Liebermann wrote:
On Sat, 11 Jan 2014 19:41:20 -0500, Jerry Stuckle wrote: I didn't say they were unknown. Just that professional integrators (including us) use better quality connectors. Could I trouble you for a photo or part number for the crimp type F connectors that you are using? I want to see what I'm missing. I can't post an image to the list, and distributors websites require logins. It won't do you any good anyway - you won't find them on ebay and the link. Sale is restricted by the manufacturers to professionals. Incidentally, SCTE IPS-TP-401 specifies that F connectors should survive a 40 lb pull test. http://www.sbcatest.com/SBCA%20connector%20recommended%20practices.pdf I once built a fixture for testing this. Many of the cheap connectors that I randomly purchased on eBay failed the test. You might want to try it with your crimp connectors. They meet all requirements. These are not cheap connectors you find on ebay. And BTW, I checked with a couple of other integrator friends today. They've never seen the cable companies around here use them, either. In fact, the only place they've seen them used is by hobbyists and other consumers. No professionals. Once a year, CED Magazine[1] provides an F-connector cross reference wall chart. Here's the one for 2011. I don't recall seeing one in the past 2 years probably because the incompatibility problems have finally stabilized: http://www.cedmagazine.com/wallcharts/2011/10/f-connector-cross-reference-chart-2011 http://www.cedmagazine.com/sites/cedmagazine.com/files/Wall_Charts/1111_F-Cconnector-WC.pdf If you inspect the chart, you'll see the various SNS Snap-n-Seal part numbers. The advertisement in the lower right is for Belden/T&B SNS connectors. None of them are used by professionals over here. What I guess(tm) happened was prior to Belden purchasing Thomas and Betts in 2010, T&B had no interest in producing a connector that would work with all RG-6/u type cables. Having many different types means everyone has to carry a larger inventory. I'm too lazy to check, but my bin contains at least 4 different F plugs for various manufacturers cables and shield types of RG-6/u. I use the above chart to make sure I don't create a mismatch. The most common connector is the SNS1P6 LRC series, color coded "blue", which fits double shielded RG-6/u. http://www.tnb.com/pubint/docs/snapnseal.pdf (11 MBytes) http://www.youtube.com/watch?v=wBZAHhH4wCo (2 min) Immediately after the acquisition, Belden introduced the "red" connector, which is a universal replacement for most of the others and will fit double, triple, and quad shielded RG-6/u. My experience with this connector hase been quite good. However, I continue to use the "blue" for double shielded RG-6/u because I have about a years inventory of connectors left. When I reorder, it will probably be the universal (or ultimate) "red" type in cool looking nickel-tin plating. Belden makes great cables, but as a whole the industry has not embraced them. The major distributors don't even carry the connectors (my guess would be due to lack of sales). And you can't use one connector for different sizes of coax without causing an impedance bump and/or having mechanical issues. The connectors we use are all for RG-6 quad (we do not use less). Locally, Comcast and Charter both use various types of T&B Snap-and-Seal connectors. I had Comcast install cable internet in our office building. That's all that I saw in use. In older installations, they use Augat LRC connectors, which are the predecessor of the current Belden/T&B connectors. I haven't seen Comcast recently, but the last I looked they didn't use Snap & Seal connectors. I haven't seen it recently because people around here don't let Comcast wire their buildings. They hire companies like ours to do it. You also mentioned compression and stripping tools. I have about 5 of them, ranging from cheap eBay junk to the T&B IT1000 which sells for about $100: http://www.mjsales.net/itemsearch.asp?FamilyID=202 The IT1000 seems to work best, although some odd extra long compression connectors, or the BNC or Phono compression connectors, require a different tool. I also stupidly bought a compression tool that only fits one manufacturers connectors, and none other. Most of my ham antennas use a compression BNC connector and/or F-connector to UHF or BNC adapter. My IT1000 is marked Augat LRC, which should give a clue as to its age. You also mentioned that you're using RG-59/u. Please note that RG-59/u lacks the foil shield(s) of RG-6/u which means that it leaks more and suffers from possible ingres problems. RG-59/u has higher attenuation: RG-59 RG-6 50 MHz 2.4 dB 1.5 dB 100 MHz 3.4 dB 2.0 dB 400 MHz 7.0 dB 4.3 dB 900 MHz 11.1 dB 6.8 dB 1000 MHz 12.0 dB 7.0 dB I've purged RG-59/u from my life many years ago. Are you sure you want to continue using the stuff. We know what we're doing. You don't know anything about our installations, our customers or our needs. Don't try to tell someone who has done this professionally for years what they should be using. And you're trying to tell EVERY professional in the United States they're doing their job wrong. We all use RG-59 at times. RG-6 is NOT appropriate for everything. Not all RG-6/u cables are equal. Here's some junk: http://sewelldirect.com/RG6-Bulk-Cable-Black-60-Braided-1000ft-Spool.asp RG-6/u with no foil shield and only 60% coverage. We know what is good and what is not. You don't need to tell us our job. -- ================== Remove the "x" from my email address Jerry, AI0K ================== |
Stacking Winegard HD-6065P antennas
On 1/12/2014 5:51 AM, Jeff wrote:
Jeff Try again. I had it back in college in the early 70's (as an EE major), and I don't think the laws of physics have changed. And the best impedance for a coax is that which matches the input and output impedance of the system, or if the input and output are of different impedances, acts as a matching stub between the two. And yes, I read the article. But you obviously don't understand it. The 30 ohms they are talking about was for ONE SPECIFIC REQUIREMENT. That does NOT mean it is true in different situations. I suggest you learn what you're talking about before you make yourself look even sillier. Well let me think; who am I doing to believe; text books on transmission line theory, data sheets for coax cables, and an article by well respected cable manufacturer), or your personal (and incorrect) theory?? Perhaps you should also point out to Belden that their article is wrong as well!! If you think that sending power over a matched cable is a specific requirement then you obviously do not understand the article. Jeff I go by my textbooks and professors. I don't believe someone who read an article about a specific installation and tried to apply that to the entire world. And I didn't say their article was wrong. I said YOUR APPLICATION of what the article said is wrong. Two entirely different things. -- ================== Remove the "x" from my email address Jerry, AI0K ================== |
Stacking Winegard HD-6065P antennas
On 1/12/2014 12:29 AM, Jeff Liebermann wrote:
On Fri, 10 Jan 2014 22:55:41 -0500, Jerry Stuckle wrote: That's theoretical. Reality is much different. I think I'll print that on a large piece of paper and have it framed for my office wall. Have you ever worked with a TDR? It's one of the tools we use regularly (and an expensive one, also). Sure. Also OTDR for fiber. I don't use the expensive stuff, unless you include the Acterna HST3000 tester that was stolen from my office a few years ago. Mostly, I built my own using a pulse generator and an oscilloscope. I'm not talking about fiber, and I'm not talking about some half-assed gadget cooked up in your basement. I'm talking about a real, professional-grade TDR. We use expensive stuff because it gives accurate results. You stated that the losses come primarily from the "impedance bump" presumably produced by the non-50 ohm connector or adapter in the line. Well, time to put that to the test. I didn't say anything about a non-50 ohm connector. The connector can be 50 ohm and still get an impedance bump. With a TDR you can see every connector on the cable (as long as they are far enough apart - typically 3-4 feet). 1. Take a length of RG-6/u coax with good connectors. Apply signal on one end from a generator. Measure the signal level on the other end with a spectrum analyzer that has a 1dB per division scale. I want to be able to see small changes. 2. After establishing a reference level, either beat on the coax cable with a hammer, squash it with a C-clamp, or flatten it with a bench vise. Squash it just enough to obtain an "impedance bump", but not a short between the center conductor and shield. Note the change in level, if you can see it. 3. Now, either un-squash the cable, or find another length of RG-6/u and attach a TDR. It can be open, shorted, or terminated. Doesn't matter. 4. Flatten the cable in the same manner as before and note the TDR display. What I expect that you'll see is that there will be almost no change in attenuation, while the TDR display will show a rather radical "impedance bump". That's because the only thing that the change in impedance along the cable length can do is create reflections. Those are a serious problem in a CATV system, but really don't involve serious signal level losses. That's theoretical. Reality is much the same. First of all, we don't crush cables to try to emulate something we can easily see in real life. Second of all, you can gimmick up something all you want with signal generators, spectrum analyzers, crushed cables, all you want. We SEE the results in real time in real installations with the appropriate test equipment. So? Dipoles aren't 50 ohm antennas. They're typically closer to 75 ohm. I guess you missed my point. If you can tolerate the 1.5:1 VSWR, the reduced attenuation and cost of 75 ohm coax makes the effort worthwhile. No, it's worthwhile because your coax will more closely match the antenna. And you can easily match the coax to the transmitter with a tuner. As for handling more power - rubbish. The current in 75 ohm coax is lower than that in 50 ohm coax, for the same power rating. Please re-read the article: www.belden.com/blog/broadcastav/50-Ohms-The-Forgotten-Impedance.cfm http://www.microwaves101.com/encyclopedia/why50ohms.cfm I read the article. Unlike you, I understand what it is saying. We use RG-59 where appropriate, like from an outlet to the set top box. But our in-wall coax runs are all RG-6 quad-shielded. RG-59/u doesn't have a foil shield, so it's more flexible. So, I guess that might work. For short lengths, the increased leakage, higher ingress, and higher attenuation can probably be tolerated. However, I use extra long RG-6/u, which somewhat compensates for the lack of flexibility. You don't know our installations. We've been in business for several years, with lots of satisfied customers. Trying to tell a professional what their job is only makes you look stupid. But we're also doing less and less coax and more and more Category cable nowadays. No MoCA installations? http://www.mocalliance.org Nope. It's used by few professionals. Coax ends up with too many problems. Category cable for runs under 100M or so and fiber for longer runs. They're OK for the hobbyist, but I don't know of any professionals who use them. In fact, checking our main wholesalers, they aren't even available through them (but other Beldon products are). Find a different distributor or ask for it by part number. Thomas and Betts SNS1P6U. We use several distributors - both U.S. and international companies. Quick check: Stocked by Allied, Newark, Tessco, Farnel(UK), MCM. Not stocked by Digikey, Mouser, Arrow. T&B distributor search: http://www.tnb.com/ps/dls/dls?ca=corp These are consumer (retail) outlets. They are not used by most professionals. -- ================== Remove the "x" from my email address Jerry Stuckle ================== |
Stacking Winegard HD-6065P antennas
On Sun, 12 Jan 2014 11:31:23 -0500, Jerry Stuckle
wrote: On 1/11/2014 11:51 PM, Jeff Liebermann wrote: On Sat, 11 Jan 2014 19:41:20 -0500, Jerry Stuckle wrote: I didn't say they were unknown. Just that professional integrators (including us) use better quality connectors. Could I trouble you for a photo or part number for the crimp type F connectors that you are using? I want to see what I'm missing. I can't post an image to the list, and distributors websites require logins. It won't do you any good anyway - you won't find them on ebay and the link. Sale is restricted by the manufacturers to professionals. Ah, secret sauce. A secret connector manufacturer and model number obtainable only from a secret distributor. No doubt made exclusively for professionals. The secret manufacturer probably made you sign an NDA before he would sell you the connectors. He can't have unprofessional hams using his secret connectors. The unobtainium plating probably makes it difficult for you to take a photograph and post it. We know what is good and what is not. You don't need to tell us our job. That's the problem. You haven't said anything about what you do, what type of systems you work on, how you do it, what connectors you use, what tools you use, where you obtain them, and the relative merits of your system to those in use by Comcast and Charter. You offer nothing that can be used, except that everything that I've been doing is wrong, that every connector that I use is junk, and that everyone in your area uses secret connectors and has magic cutters that last nearly forever. You might know what is good for "professionals", but I have no clue what that might be. For me, questioning authority, trying something different, and testing assumptions is a learning experience. I'm doing a 10 year running experiment on the effectiveness of using 1" PTFE wrap over commodity RF connectors for waterproofing. I'm testing 75 ohm coax where 50 ohms is standard. I use F connectors in a ham radio environment for which they were never intended. I've designed and build some rather odd antennas. I question and verify conventional wisdom, claims, standards, test results, and specifications. I've made both big and small mistakes, irritated the experts, and occasionally inspired vendors into modifying their data sheets and claims. I look for new ideas that I can use (or steal) and had hoped that perhpas your secret F connector was in some way better than the common Snap-n-Seal connector. I'm disappointed. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
Stacking Winegard HD-6065P antennas
On 1/12/2014 12:00 PM, Jeff wrote:
I go by my textbooks and professors. I don't believe someone who read an article about a specific installation and tried to apply that to the entire world. And I didn't say their article was wrong. I said YOUR APPLICATION of what the article said is wrong. Two entirely different things. The point that are missing is that the graphs in that article are independent of application. They represent the true picture for correctly terminated coax. You also seem not to understand how those graphs are derived. Jeff OK, I give up. From reading one chart, you know more than all of the physicists, professors and engineers in the world. And you can write the book that contradicts every physics textbook out there. You're THE MAN! I bow to your expertise. NOT! -- ================== Remove the "x" from my email address Jerry Stuckle ================== |
Stacking Winegard HD-6065P antennas
On 1/12/2014 11:14 AM, Jeff wrote:
Try again. I had it back in college in the early 70's (as an EE major), and I don't think the laws of physics have changed. And the best impedance for a coax is that which matches the input and output impedance of the system, or if the input and output are of different impedances, acts as a matching stub between the two. And yes, I read the article. But you obviously don't understand it. The 30 ohms they are talking about was for ONE SPECIFIC REQUIREMENT. That does NOT mean it is true in different situations. I suggest you learn what you're talking about before you make yourself look even sillier. Jerry, let me put you out of your misery. The peak power capability of coax is not set by the ohmic losses but by the breakdown voltage, that is where the ~30 ohms for best max power handling comes from. Which has absolutely nothing to do with what we were discussing. And breakdown voltage of the coax is dependent on the dielectric only (material and thickness). While these will affect impedance, saying 30 ohm impedance is the "best" impedance is not true. The max *average* power capability is governed by heating of the cable due to the losses per until length (both resistive and reactive). The losses being proportional not the the cross sectional area of the conductors but to *surface* area (due to skin depth considerations). Which is directly related to the square of the current through the coax. The lower the impedance of the coax, the higher the current for the same power. Now whilst it is true that 75ohm cable will have marginally lower loss than 50 ohm cable, this is only true when the inner conductor diameter is kept constant and the 75 ohm cable hase a larger shield diameter. For cables with the same outside diameter the losses for 75ohm are greater due to the smaller diameter (and hence lower surface area) of the inner. So in practical terms for the same size cable 50 ohm has lower loss, greater average power capability, and greater peak power capability. If you don't believe me these figures can be easily verified by looking at the specs of 50 & 75 ohm cable of the same shield diameter. Jeff But as I said - you're the man. You are able to interpret this chart and contradict every physics textbook, engineer and professor in the world. You are the expert! NOT! -- ================== Remove the "x" from my email address Jerry Stuckle ================== |
Stacking Winegard HD-6065P antennas
On 1/12/2014 12:40 PM, Jeff Liebermann wrote:
On Sun, 12 Jan 2014 11:31:23 -0500, Jerry Stuckle wrote: On 1/11/2014 11:51 PM, Jeff Liebermann wrote: On Sat, 11 Jan 2014 19:41:20 -0500, Jerry Stuckle wrote: I didn't say they were unknown. Just that professional integrators (including us) use better quality connectors. Could I trouble you for a photo or part number for the crimp type F connectors that you are using? I want to see what I'm missing. I can't post an image to the list, and distributors websites require logins. It won't do you any good anyway - you won't find them on ebay and the link. Sale is restricted by the manufacturers to professionals. Ah, secret sauce. A secret connector manufacturer and model number obtainable only from a secret distributor. No doubt made exclusively for professionals. The secret manufacturer probably made you sign an NDA before he would sell you the connectors. He can't have unprofessional hams using his secret connectors. The unobtainium plating probably makes it difficult for you to take a photograph and post it. Nope, professional grade connectors which are only available to professionals. But you obviously know more than the professionals about our business and our product. We know what is good and what is not. You don't need to tell us our job. That's the problem. You haven't said anything about what you do, what type of systems you work on, how you do it, what connectors you use, what tools you use, where you obtain them, and the relative merits of your system to those in use by Comcast and Charter. You offer nothing that can be used, except that everything that I've been doing is wrong, that every connector that I use is junk, and that everyone in your area uses secret connectors and has magic cutters that last nearly forever. No, and it doesn't matter. But even though you don't know, you know better then I what I do, and what components I should be using. Sorry. I don't use the cheap stuff available to you. No, they're not "secret sauce". But they aren't available on Ebay (or at Radio Shack). And unlike what you have told me, I haven't said ANYTHING you do is wrong. Neither did I say anything you use is junk. I just said PROFESSIONALS don't use it. You might know what is good for "professionals", but I have no clue what that might be. For me, questioning authority, trying something different, and testing assumptions is a learning experience. I'm doing a 10 year running experiment on the effectiveness of using 1" PTFE wrap over commodity RF connectors for waterproofing. I'm testing 75 ohm coax where 50 ohms is standard. I use F connectors in a ham radio environment for which they were never intended. I've designed and build some rather odd antennas. I question and verify conventional wisdom, claims, standards, test results, and specifications. I've made both big and small mistakes, irritated the experts, and occasionally inspired vendors into modifying their data sheets and claims. I look for new ideas that I can use (or steal) and had hoped that perhpas your secret F connector was in some way better than the common Snap-n-Seal connector. I'm disappointed. But you seem to be telling me left and right what I should and should not be using. You want to learn? Go to school. Learn what professionals use. I'm not about to waste my time here on usenet trying to educate someone who argues with everything I say. I'm outta here. -- ================== Remove the "x" from my email address Jerry, AI0K ================== |
Stacking Winegard HD-6065P antennas
On Sun, 12 Jan 2014 16:32:40 -0500, Jerry Stuckle
wrote: Nope, professional grade connectors which are only available to professionals. Please advise when you are able to identify or photograph your secret connectors. I would also be interested in the name of your distributor that has a private stock of professional only connectors, but since I don't intend to buy from them, that's optional. But you obviously know more than the professionals about our business and our product. I've been very careful to only mention what I do, and what the local cable companies are doing. My only suggestion to you was to measure the loss and view the reflections of an "impedance bump" artificially produced with a squashed coax cable. If you would like me to tell you how to run your business and manage your product, please email for my list of services and I will provide an estimate. No, and it doesn't matter. But even though you don't know, you know better then I what I do, and what components I should be using. True. I know nothing about what you are doing, what you are using, and how you are doing it. Most commonly, you only indicate what you are NOT doing. That's not very helpful. But you seem to be telling me left and right what I should and should not be using. See above. Except for testing your "impedance bump" theory of attenuation, I haven't told you what you should be doing or using. I normally charge for commercial advice. You want to learn? Go to school. Learn what professionals use. That probably wouldn't be a bad idea if I had the time. I could use some more wallpaper. However, if I do go back to skool, it will probably be to teach. Learning how to use compression connectors does not require a class. There are YouTube videos and instruction documents that are more than adequate. Some people learn best from a formal classroom education. I do better getting my hands dirty. I'm not about to waste my time here on usenet trying to educate someone who argues with everything I say. It's called a discussion, which has been interesting, but not very informative. I'm outta here. Please come back when you are able to identify your secret connectors. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
Stacking Winegard HD-6065P antennas
On Sun, 12 Jan 2014 11:48:13 -0500, Jerry Stuckle
wrote: I'm not talking about fiber, and I'm not talking about some half-assed gadget cooked up in your basement. I'm talking about a real, professional-grade TDR. Make and model please? I used to drag around a Tek 1503 but rarely used it. It was most useful for find broken cables, usually where the rats chewed through the wires. Also, for measuring the length of cables on a roll that didn't have ft markers. One day, I needed it, and it was dead, probably from bouncing around in my truck. Rather than fix it, I sold it as-is. http://www.ebay.com/itm/131091152872 I was already carrying a scope, so I saw no reason to buy another scope just to get a TDR. So, I designed and built a TDR, mostly checking CAT5 and telco wires, not coax. Something like this: http://www.epanorama.net/circuits/tdr.html We use expensive stuff because it gives accurate results. I use cheap stuff because I know its limitations and can work within those limitations. Much as I value my money, old test equipment is good enough for most things. http://www.learnbydestroying.com/jeffl/pics/home/slides/test-equip-mess.html You stated that the losses come primarily from the "impedance bump" presumably produced by the non-50 ohm connector or adapter in the line. Well, time to put that to the test. I didn't say anything about a non-50 ohm connector. The connector can be 50 ohm and still get an impedance bump. With a TDR you can see every connector on the cable (as long as they are far enough apart - typically 3-4 feet). If the connectors were a prefect 50 ohms, you wouldn't see any reflection. Therefore, either the connectors are not quite 50 ohms, your coax is not quite 50 ohms, you have a high resistance shield connection, or this is one of your cases where theory fails to accommodate your reality. That's theoretical. Reality is much the same. First of all, we don't crush cables to try to emulate something we can easily see in real life. I crush, chop, dissect, and set fire to cable to see how they're built. Amazing what you find if you look inside of things. However, since you have an aversion to crushing coax able, you can get the same effect with a short length of different impedance coax cable and some adapters. Just insert where I suggested you crush the coax, and you should see it clearly on the TDR. Then replace it with an identical length of the correct impedance cable and compare the losses. At worst, the loss difference will be fractions of a dB. That suggests that your "impedance bump" isn't really responsible for much loss. Of course, you have set fire to plenum, non-plenum, and riser CAT5 cables to see how they burn. I think you might be surprised. Learn by Destroying(tm). Second of all, you can gimmick up something all you want with signal generators, spectrum analyzers, crushed cables, all you want. For those that believe theory, proof by bench testing is possible. For those who do not believe or understand theory, no amount of test equipment will ever prove anything. Theory and testing go hand in hand. If there's a discrepancy, then either one of them is wrong, or the procedure is flawed. We SEE the results in real time in real installations with the appropriate test equipment. You see the results, but for some odd reason, I haven't seen your results or list of appropriate professional test equipment. Why always so vague and non-specific? FoN (Fear of Numbers)? So? Dipoles aren't 50 ohm antennas. They're typically closer to 75 ohm. I guess you missed my point. If you can tolerate the 1.5:1 VSWR, the reduced attenuation and cost of 75 ohm coax makes the effort worthwhile. No, it's worthwhile because your coax will more closely match the antenna. And you can easily match the coax to the transmitter with a tuner. Tuners can be lossy. Try this T-tuner Java app on the lower bands. http://fermi.la.asu.edu/w9cf/tuner/tuner.html The starting values (hit the AutoTune button) produce a 2dB loss at 160 meters. The losses are much less on the higher bands. Q=100 for the inductor seems a bit high. Please re-read the article: www.belden.com/blog/broadcastav/50-Ohms-The-Forgotten-Impedance.cfm http://www.microwaves101.com/encyclopedia/why50ohms.cfm I read the article. Unlike you, I understand what it is saying. What part of the following do you disagree with and why? (It's all in the above articles). Please try to be specific: 1. Loss for approximately equal size is less for 75 ohm cable. 2. 50 ohm cable will tolerate a higher power due to a higher voltage breakdown. 3. Maximum power is with about 30 ohm coax cable. http://www.microwaves101.com/encyclopedia/coax_power.cfm 4. Mismatch loss from 75 ohm cable in a 50 ohm system is 0.18dB. 5. If the mismatch loss from using 75 ohm cable is less than the difference in attenuation for a comparable 50 ohm cable, and there are no high power levels involved, then it is better to use 75 ohm cable and tolerate the mismatch. You don't know our installations. We've been in business for several years, with lots of satisfied customers. Trying to tell a professional what their job is only makes you look stupid. I only debate a persons ideas and never attack them personally. If you are unable to do that, you lack "professionalism" which presumably goes with your professional title. No MoCA installations? http://www.mocalliance.org Nope. It's used by few professionals. Coax ends up with too many problems. Category cable for runs under 100M or so and fiber for longer runs. Fiber is generally better and much more expensive. I also do fiber where possible. However, when faced with a large apartment complex, with no possible way to economically rewire the building, I was forced to consider what could be done with the existing wiring. The building had CAT3 going to all the apartments, but CAT3 is useless (no twists). Even DSL had crosstalk problems. I tried to use the CAT3 as a pull line to drag in CAT5, but that also failed (no smurf tubes in the walls). I also tried 2.4/5.7 wireless, which proved erratic because of aluminum foil backed insulation, untouchable firewalls, and interference from existing Wi-Fi systems. So, I tired MoCA and it worked. http://www.netgear.com/service-providers/products/in-home-connectivity/moca-bridges/ http://www.netgear.com/service-providers/products/in-home-connectivity/moca-bridges/wm2500rp.aspx They're now bringing in Comcast TV, internet, and phone via coax, using MoCA to distribute internet around each apartment. Depending on wiring, Jperf shows about 100-300 Mbits/sec between clients (16 maximum). Speedtest shows whatever was ordered from Comcast from/to the internet, typically 22/2 Mbit/sec. To be honest, things did not go smoothly. MoCA is expensive. The isolation between apartments on the main Comcast splitter was not enough to prevent leakage between bridges. Using couplers instead of splitters were a big help. I also needed to select a different channel, which is not allowed by every MoCA unit. I started with Actiontek, which was cheaper, but does NOT offer channel selection and was therefore useless. Some of the apartments had satellite TV, which had to be accommodated with diplexers. However, the worst problem was that I rapidly became the single point of contact for any problem with the system. Fortunately, I was conveniently underbid for the maintenance contract by another service company, which has taken over the system. To the best of my knowledge, it's still running nicely after about 18 months. Next time you run into a situation that does not economically allow a retrofit of fiber or CAT5/6, and there's existing coax, think about MoCA. Find a different distributor or ask for it by part number. Thomas and Betts SNS1P6U. We use several distributors - both U.S. and international companies. Did you any of them if they specifically carry T&B or stock T&B SNS1P6U connectors? Where we left off, you were having difficulties finding a stocking distributor. Are either of your unspecified distributors on the T&T distributor search page? http://www.tnb.com/ps/dls/dls?ca=corp Within 25 miles of your location, it shows 5 stocking distributors with 13 locations. Quick check: Stocked by Allied, Newark, Tessco, Farnel(UK), MCM. Not stocked by Digikey, Mouser, Arrow. T&B distributor search: http://www.tnb.com/ps/dls/dls?ca=corp These are consumer (retail) outlets. They are not used by most professionals. None of those listed above have a retail (brick and mortar) store. Many do sell online and from catalogs, but even the largest distributors do that. Legally, if they charge sales tax, they are a "retail" operation. Offhand, I can't think of a single large distributor that does not accept taxable sales or requires a resale permit in order to process an order. There used to be those as B2B (business to business) operations, but not any more, because the growth of internet commerce has made retail processing a necessity. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
Stacking Winegard HD-6065P antennas
On 1/12/2014 7:24 PM, Jeff Liebermann wrote:
On Sun, 12 Jan 2014 11:48:13 -0500, Jerry Stuckle wrote: I'm not talking about fiber, and I'm not talking about some half-assed gadget cooked up in your basement. I'm talking about a real, professional-grade TDR. Make and model please? It's in my office, and not my lap. And quite frankly, I'm not about to go out of my way to follow up because it's none of your business. You're trolling now, and I don't respond to trolls. rest of garbage snipped because it just proves you have no idea what you're talking about. One other comment. No, you won't go back to school not because you don't need another piece of paper on the wall. You already think you know everything. And it just might ruin your day to find out how wrong you are. -- ================== Remove the "x" from my email address Jerry Stuckle ================== |
Stacking Winegard HD-6065P antennas
On Sun, 12 Jan 2014 21:10:17 -0500, Jerry Stuckle
wrote: On 1/12/2014 7:24 PM, Jeff Liebermann wrote: On Sun, 12 Jan 2014 11:48:13 -0500, Jerry Stuckle wrote: I'm not talking about fiber, and I'm not talking about some half-assed gadget cooked up in your basement. I'm talking about a real, professional-grade TDR. Make and model please? It's in my office, and not my lap. And quite frankly, I'm not about to go out of my way to follow up because it's none of your business. No doubt a private label TDR made especially for professionals and considered a trade secret by it owners. Gosh, I want one of those. You're trolling now, and I don't respond to trolls. Not exactly trolling but close. I'm asking you to substantiate your claims and to supply specific makers and model numbers. rest of garbage snipped because it just proves you have no idea what you're talking about. One other comment. No, you won't go back to school not because you don't need another piece of paper on the wall. You already think you know everything. I'm not sure I can decode your comment with it's 3 negations. I said that I *DO* need another piece of paper for my wall. My 2013 calendar expired last week, and I need something to fill the wall space. Obtaining a new 2014 calendar is both costly and time consuming. It's easier to just fill the space with another diploma. www.ebay.com/sch/i.html?_nkw=fake+university+diploma And it just might ruin your day to find out how wrong you are. You first, then you can cross examine me. You stated that I don't understand the two articles on 50 versus 75 ohms. You also stated that you do understand the articles. Then please explain them to me. The following are my claims, all derived from the articles. Where in the following am I wrong and why? 1. Loss for approximately equal size is less for 75 ohm cable. 2. 50 ohm cable will tolerate a higher power due to a higher voltage breakdown. 3. Maximum power is with about 30 ohm coax cable. http://www.microwaves101.com/encyclopedia/coax_power.cfm 4. Mismatch loss from 75 ohm cable in a 50 ohm system is 0.18dB. 5. If the mismatch loss from using 75 ohm cable is less than the difference in attenuation for a comparable 50 ohm cable, and there are no high power levels involved, then it is better to use 75 ohm cable and tolerate the mismatch. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
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