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New random Wire antenna in progress
Well, put up a new inverted-L antenna - 30 feet up a tree, 60 feet
across horz and over the house rooftop (nowhere else to go!), base ~20 feet from house. Using a winradio 9:1 unun matcher at the base, *not yet grounded*. In fact, so far none of the RF chain on this antenna is grounded. So far, so good - noise level *fairly* low (lower on almots all freqs than my DX-Ultra), AND signal strength on most bands roughly the same, varying depending on the band. One good thing I do notice is that on strong MW stations, he antenna does *NOT* reveal a 60 Hz background hum like the DX-Ultra does - I consider this a good sign. The far end is about 25 feet from the higher-tension power lines out back, and the near end is about 15 feet from the low-tension lines in front. Next steps - 1 - Ground the 9:1 unun 2 - Bury the coax from house to base of antenna (about 18 feet underground) 3 - Install RF isolator (Either Radioworks or Wellbrook AFI5030) at the house with or without a ground stake connection, depending on what works the best. Have not had great reception so far this week, so no chance to really give it a workout. Further reports to come. Thanks, guys, for all the input so far! |
New random Wire antenna in progress
On 01/31/2011 11:55 AM, bpnjensen wrote:
Well, put up a new inverted-L antenna - 30 feet up a tree, 60 feet across horz and over the house rooftop (nowhere else to go!), base ~20 feet from house. Using a winradio 9:1 unun matcher at the base, *not yet grounded*. In fact, so far none of the RF chain on this antenna is grounded. So far, so good - noise level *fairly* low (lower on almots all freqs than my DX-Ultra), AND signal strength on most bands roughly the same, varying depending on the band. One good thing I do notice is that on strong MW stations, he antenna does *NOT* reveal a 60 Hz background hum like the DX-Ultra does - I consider this a good sign. The far end is about 25 feet from the higher-tension power lines out back, and the near end is about 15 feet from the low-tension lines in front. Next steps - 1 - Ground the 9:1 unun 2 - Bury the coax from house to base of antenna (about 18 feet underground) 3 - Install RF isolator (Either Radioworks or Wellbrook AFI5030) at the house with or without a ground stake connection, depending on what works the best. Have not had great reception so far this week, so no chance to really give it a workout. Further reports to come. Thanks, guys, for all the input so far! It's a rule that putting up a new antenna causes bad dx space weather. Like washing your car makes it rain. |
New random Wire antenna in progress
On Jan 31, 4:13*pm, dave wrote:
On 01/31/2011 11:55 AM, bpnjensen wrote: Well, put up a new inverted-L antenna - 30 feet up a tree, 60 feet across horz and over the house rooftop (nowhere else to go!), base ~20 feet from house. *Using a winradio 9:1 unun matcher at the base, *not yet grounded*. *In fact, so far none of the RF chain on this antenna is grounded. *So far, so good - noise level *fairly* low (lower on almots all freqs than my DX-Ultra), AND signal strength on most bands roughly the same, varying depending on the band. *One good thing I do notice is that on strong MW stations, he antenna does *NOT* reveal a 60 Hz background hum like the DX-Ultra does - I consider this a good sign. *The far end is about 25 feet from the higher-tension power lines out back, and the near end is about 15 feet from the low-tension lines in front. *Next steps - 1 - Ground the 9:1 unun 2 - Bury the coax from house to base of antenna (about 18 feet underground) 3 - Install RF isolator (Either Radioworks or Wellbrook AFI5030) at the house with or without a ground stake connection, depending on what works the best. Have not had great reception so far this week, so no chance to really give it a workout. Further reports to come. *Thanks, guys, for all the input so far! It's a rule that putting up a new antenna causes bad dx space weather. Like washing your car makes it rain. ....or like a new telescope eyepiece means cloudy weather :-D |
New random Wire antenna in progress
On Feb 1, 1:48*am, bpnjensen wrote:
On Jan 31, 4:13*pm, dave wrote: On 01/31/2011 11:55 AM, bpnjensen wrote: Well, put up a new inverted-L antenna - 30 feet up a tree, 60 feet across horz and over the house rooftop (nowhere else to go!), base ~20 feet from house. *Using a winradio 9:1 unun matcher at the base, *not yet grounded*. *In fact, so far none of the RF chain on this antenna is grounded. *So far, so good - noise level *fairly* low (lower on almots all freqs than my DX-Ultra), AND signal strength on most bands roughly the same, varying depending on the band. *One good thing I do notice is that on strong MW stations, he antenna does *NOT* reveal a 60 Hz background hum like the DX-Ultra does - I consider this a good sign. *The far end is about 25 feet from the higher-tension power lines out back, and the near end is about 15 feet from the low-tension lines in front. *Next steps - 1 - Ground the 9:1 unun 2 - Bury the coax from house to base of antenna (about 18 feet underground) 3 - Install RF isolator (Either Radioworks or Wellbrook AFI5030) at the house with or without a ground stake connection, depending on what works the best. Have not had great reception so far this week, so no chance to really give it a workout. Further reports to come. *Thanks, guys, for all the input so far! It's a rule that putting up a new antenna causes bad dx space weather. Like washing your car makes it rain. ...or like a new telescope eyepiece means cloudy weather :-D- Hide quoted text - - Show quoted text - aka as Murphy's Law ! |
New random Wire antenna in progress
Do you run with RF gain all the way up? I don't. I use a lot of AF gain and turn the AGC off and ride the RF gain (use that for a volume control). That gets the noise way down (until somebody flips an incandescent light switch and the "pop" goes through my brain). I did my deep urban DXing on a 2010 (on a 30' umbilical) and an R390-A (120' random wire connected directly to back of radio). Biggest power lines overhead at right angle to random wire. The R390-A's what got me hooked on pro grade receivers. |
New random Wire antenna in progress
On Feb 1, 9:04*am, dave wrote:
Do you run with RF gain all the way up? I don't. I use a lot of AF gain and turn the AGC off and ride the RF gain (use that for a volume control). That gets the noise way down (until somebody flips an incandescent light switch and the "pop" goes through my brain). I did my deep urban DXing on a 2010 (on a 30' umbilical) and an R390-A (120' random wire connected directly to back of radio). Biggest power lines overhead at right angle to random wire. The R390-A's what got me hooked on pro grade receivers. It depends on the situation. I only rarely turn off the AGC, but I do ride the RF Gain quite a bit, partly because of this effect you describe and partly because it really helps the S-AM work properly (People complain about the Icom R-75 S-AM, even with Kiwa mods, but I can eliminate virtually all selective fading with the RF Gain set properly). However, I will give the method you describe a shot. How did those powerlines affect your reception? |
New random Wire antenna in progress
On Feb 1, 8:58*am, RHF wrote:
On Jan 31, 11:55*am, bpnjensen wrote: Well, put up a new inverted-L antenna - 30 feet up a tree, 60 feet across horz and over the house rooftop (nowhere else to go!), base ~20 feet from house. *Using a winradio 9:1 unun matcher at the base, *not yet grounded*. *In fact, so far none of the RF chain on this antenna is grounded. *So far, so good - noise level *fairly* low (lower on almots all freqs than my DX-Ultra), AND signal strength on most bands roughly the same, varying depending on the band. *One good thing I do notice is that on strong MW stations, he antenna does *NOT* reveal a 60 Hz background hum like the DX-Ultra does - I consider this a good sign. *The far end is about 25 feet from the higher-tension power lines out back, and the near end is about 15 feet from the low-tension lines in front. *Next steps - - 1 - Ground the 9:1 unun - 2 - Bury the coax from house to base of antenna - (about 18 feet underground) You can use 1/2" Polyethylene Tubing to Buryhttp://www.dripdepot.com/1045 your Coax in if you don't want to use PVC Pipe. *. Seal the Tubing ends with one of these.http://www.touch-n-foam.com/products.php *. - 3 - Install RF isolator (Either Radioworks or - Wellbrook AFI5030) at the house with or - without a ground stake connection, Usually you should try and get this Ground Rod were the Coax is coming out of the Ground; and as close as you can get it to were the Coax is about to enter the House. *. - depending on what works the best. - - Have not had great reception so far this week, - so no chance to really give it a workout. Then things can only get better. - Further reports to come. -*Thanks, guys, for all the input so far! Post It When You Hear Them :o) ~ RHF *. *. Good idea on the tubing. Since I already have the PL-259s on the cable, I may go for 3/4" or 7/8" ID tubing (they should snug through that size tube, IIRC). I already have the 8' ground stake in at the edge of the foundation, so it's practically plug and play if I ground that RF isolator. I was thinking of using CoaxSeal for the tube ends, since I have a mess of it. Question - does the additional Poly tube around the coax diminish the capacity to provide (presumably useful) inductive ground for the buried cable? If the coax is not "entubed", does the covering break down in soil? I have RG8X for the run...PVC coating IIRC. Bruce |
New random Wire antenna in progress
On 11-02-01 11:22 AM, bpnjensen wrote:
Question - does the additional Poly tube around the coax diminish the capacity to provide (presumably useful) inductive ground for the buried cable? Seems to me that anything resembling an inductive ground would be a bad thing. The inductive coupling effect would vary completely with the frequency of the signal, proximity, length, etc. Not good. Don't settle for anything less than a real, lowest possible impedance, honest to G_d, mechanically connected ground. I usually smear the wire connection and electrode with vaseline after having sandpapered them. Then do your clamping. A plastic cup inverted over the end of the ground rod will keep the rain out of the joint. mike |
New random Wire antenna in progress
On 2/1/11 12:41 , m II wrote:
On 11-02-01 11:22 AM, bpnjensen wrote: Question - does the additional Poly tube around the coax diminish the capacity to provide (presumably useful) inductive ground for the buried cable? Seems to me that anything resembling an inductive ground would be a bad thing. The inductive coupling effect would vary completely with the frequency of the signal, proximity, length, etc. Not good. Don't settle for anything less than a real, lowest possible impedance, honest to G_d, mechanically connected ground. I usually smear the wire connection and electrode with vaseline after having sandpapered them. Then do your clamping. A plastic cup inverted over the end of the ground rod will keep the rain out of the joint. mike Or you can wrap it with CoaxSeal. Teflon tape works very well, for this, too. |
New random Wire antenna in progress
On Feb 1, 10:41*am, m II wrote:
On 11-02-01 11:22 AM, bpnjensen wrote: Question - does the additional Poly tube around the coax diminish the capacity to provide (presumably useful) inductive ground for the buried cable? Seems to me that anything resembling an inductive ground would be a bad thing. The inductive coupling effect would vary completely with the frequency of the signal, proximity, length, etc. Not good. Don't settle for anything less than a real, lowest possible impedance, honest to G_d, mechanically connected ground. I usually smear the wire connection and electrode with vaseline after having sandpapered them. Then do your clamping. A plastic cup inverted over the end of the ground rod will keep the rain out of the joint. mike Well, that's not quite what I meant - I am sorry if I was unclear. IIRC, there is nothing at all wrong with burying a cable, and in fact it helps to keep the RFI away from the run, as well as keeping the outer braid near the earthen ground and helping to bleed away currents travelling along the braid. That is what I was asking about - whether a poly tube would lessen this desirable effect. I have every intention of grounding the 9:1 unun, presuming it will enhance performance (if it does not, I'll disconnect it). If necessary, I'll also install the RF Isolator and try it both grounded and ungrounded. I had never heard that it was necessary to keep a solid mechanical ground water-free, although I guess I can see the value. I don't understand what vaseline does - just protect against corrosion? I doubt if it would help the electrical connection. |
New random Wire antenna in progress
On Feb 1, 10:41*am, m II wrote:
On 11-02-01 11:22 AM, bpnjensen wrote: Question - does the additional Poly tube around the coax diminish the capacity to provide (presumably useful) inductive ground for the buried cable? Seems to me that anything resembling an inductive ground would be a bad thing. The inductive coupling effect would vary completely with the frequency of the signal, proximity, length, etc. Not good. - Don't settle for anything less than a real, - lowest possible impedance, honest to G_d, - mechanically connected ground. - I usually smear the wire connection and - electrode with vaseline after having sandpapered them. - Then do your clamping. - A plastic cup inverted over the end of the - ground rod will keep the rain out of the joint. - - mike Conductive Grease "NO-OX-ID" http://www.sanchem.com/aSpecialE.htm...FRiAgwodThlG2g CRC® Dielectric Grease http://www.acehardware.com/product/i...ductId=1443552 |
New random Wire antenna in progress
On 02/01/2011 12:38 PM, bpnjensen wrote:
Well, that's not quite what I meant - I am sorry if I was unclear. IIRC, there is nothing at all wrong with burying a cable, and in fact it helps to keep the RFI away from the run, as well as keeping the outer braid near the earthen ground and helping to bleed away currents travelling along the braid. That is what I was asking about - whether a poly tube would lessen this desirable effect. I have every intention of grounding the 9:1 unun, presuming it will enhance performance (if it does not, I'll disconnect it). If necessary, I'll also install the RF Isolator and try it both grounded and ungrounded. I had never heard that it was necessary to keep a solid mechanical ground water-free, although I guess I can see the value. I don't understand what vaseline does - just protect against corrosion? I doubt if it would help the electrical connection. You're not supposed to use braid for grounds. |
New random Wire antenna in progress
On 02/01/2011 12:47 PM, RHF wrote:
On Feb 1, 10:41 am, m wrote: On 11-02-01 11:22 AM, bpnjensen wrote: Question - does the additional Poly tube around the coax diminish the capacity to provide (presumably useful) inductive ground for the buried cable? Seems to me that anything resembling an inductive ground would be a bad thing. The inductive coupling effect would vary completely with the frequency of the signal, proximity, length, etc. Not good. - Don't settle for anything less than a real, - lowest possible impedance, honest to G_d, - mechanically connected ground. - I usually smear the wire connection and - electrode with vaseline after having sandpapered them. - Then do your clamping. - A plastic cup inverted over the end of the - ground rod will keep the rain out of the joint. - - mike Conductive Grease "NO-OX-ID" http://www.sanchem.com/aSpecialE.htm...FRiAgwodThlG2g CRC® Dielectric Grease http://www.acehardware.com/product/i...ductId=1443552 . Heat Sink Compound {Zink Oxide} http://www.radioshack.com/product/in...ductId=2102858 * Rite Aid Zinc Oxide, Ointment http://www.amazon.com/dp/B00009M8JK even remembering using fluoride toothpaste hey - what works... works ! - iane ~ RHF . . You are freaking nuts. |
New random Wire antenna in progress
On Feb 1, 8:28*am, dave wrote:
On 01/31/2011 11:09 PM, wrote: On Feb 1, 1:48 am, *wrote: ...or like a new telescope eyepiece means cloudy weather :-D- Hide quoted text - - Show quoted text - aka as Murphy's Law ! No. Murphy's Law is based on actual physical law. What we describe above is stupid coincidence. Murphy's Law states that the mechanism will perform as designed and built and that it cannot do otherwise. It is a very serious thing. I suggest you ask any Irishman/woman ! They WILL tell you ... |
New random Wire antenna in progress
On 02/01/2011 06:53 PM, m II wrote:
On 11-02-01 05:46 PM, dave wrote: I haven't used petroleum jelly since WD-40 started showing up in spray cans. The point is to keep air away from the metal, a thin layer works as well as copious globs. I don't buy WD40 anymore. I've had two large cans in a row get clogged internally, so nothing would come out. The cans were still pretty much full. Full and useless.... The stuff doesn't do very much successfully. It makes a rotten lubricant. The only thing it actually does well is displace water, which is where it got its name, WaterDisplacer. One can assume it was recipe #40 that finally worked. I think Howard Hughes had something to do with it. mike I think I have the same can I bought in 1981. I use Liquid Wrench on stuck bolts, 3 in 1 Oil for light lubricating. 5W30 is in my old school pump can for the swamp coolers, pillow blocks, etc. |
The Wet Head is Dead "Greasy Kids' Stuff"
On 02/01/2011 07:03 PM, RHF wrote:
On Feb 1, 4:46 pm, wrote: On 02/01/2011 03:52 PM, RHF wrote: - You are freaking nuts. Dave, Let's see some sort of stay-in-place 'conductive' paste -or- 'Vaseline' {pure Petroleum Jelly} which gets hot and runs-off a/o gets dirty. like a squirrel getting ready for winter ~ RHF . - I haven't used petroleum jelly since WD-40 - started showing up in spray cans. The point - is to keep air away from the metal, a thin layer - works as well as copious globs. Dave 'copious globs' works for me ...cause... I was never a "Brylcreem" kind of guy ~ RHF http://www.collectibles-articles.com...0599778204.jpg . . |
New random Wire antenna in progress
On Feb 1, 6:53*pm, m II wrote:
On 11-02-01 05:46 PM, dave wrote: I haven't used petroleum jelly since WD-40 started showing up in spray cans. The point is to keep air away from the metal, a thin layer works as well as copious globs. - I don't buy WD40 anymore. I've had two large cans - in a row get clogged internally, so nothing would come - out. The cans were still pretty much full. - Full and useless.... - - The stuff doesn't do very much successfully. - It makes a rotten lubricant. The only thing it actually - does well is displace water, which is where it got its - name, Water Displacer. One can assume it was - recipe #40 that finally worked. - - I think Howard Hughes had something to do with it. - - mike CAUTION : The Spray Fumes from WD40 are relatively Toxic and for some people with an Asthmatic a/o other Respiratory Conditions can bring on an attack a/o Chest Cold like Symptoms. * Use a Filter/Mask when using WD40. * Use WD40 in a well ventilated area. * Wash your Hands after use {Wear Gloves} White Lithium Grease in a Tube works well http://www.amazon.com/dp/B000KXLR7M and generally stays put. ~ RHF |
New random Wire antenna in progress
On Feb 2, 5:14*am, dave wrote:
On 02/01/2011 06:53 PM, m II wrote: On 11-02-01 05:46 PM, dave wrote: I haven't used petroleum jelly since WD-40 started showing up in spray cans. The point is to keep air away from the metal, a thin layer works as well as copious globs. I don't buy WD40 anymore. I've had two large cans in a row get clogged internally, so nothing would come out. The cans were still pretty much full. Full and useless.... The stuff doesn't do very much successfully. It makes a rotten lubricant. The only thing it actually does well is displace water, which is where it got its name, WaterDisplacer. One can assume it was recipe #40 that finally worked. I think Howard Hughes had something to do with it. mike I think I have the same can I bought in 1981. I use Liquid Wrench on stuck bolts, 3 in 1 Oil for light lubricating. 5W30 is in my old school pump can for the swamp coolers, pillow blocks, etc. Ah the good old "3-In-One Oil" Company http://en.wikipedia.org/wiki/3-in-1 -why- The Name "3-In-One Oil" -to- "Clean, Lubricate and Protect" -now- "The Tool Kit In A Can" http://www.3inone.com/ Since 1894 . . . Now That’s a Long Lasting Oil ! http://www.3inone.com/about/history/ |
New random Wire antenna in progress
On Feb 1, 6:53*pm, m II wrote:
On 11-02-01 05:46 PM, dave wrote: I haven't used petroleum jelly since WD-40 started showing up in spray cans. The point is to keep air away from the metal, a thin layer works as well as copious globs. - I don't buy WD40 anymore. - I've had two large cans in a row get clogged - internally, so nothing would come out. - The cans were still pretty much full. - Full and useless.... Have you tried the "Non-Aerosol" WD-40 Trigger Pro ? http://www.wd40.com/products/trigger-pro/ |
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