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What Does "RG-6" {Coax Cable} Mean ?
David wrote: RHF wrote: On Dec 31, 9:17 am, msg wrote: RHF wrote: snip Extra Protection* for the Buried Coax Cable can be obtained by using Half-Inch (1/2") Black Polyethylene Drip Water Tubing {Hose} as an added Layer of Protection for Buried Coax Cable against damage from Plants, Tree Roots and Animals. I have coax running through 1 1/2" PVC buried at 2 feet but be advised that you must provide a means of draining condensation or include desiccants or provide dry air flow to avoid water in your cables. In my case, I periodically blow out the pipe with compressed air and also have a 1 inch per foot grade to encourage drainage to one end where the water can then be extracted (blown out). Regards, Michael MSG - Good Advise. ~ RHF . Belden makes a Direct Burial RG-8X, 7808 I think. Times Microwave also has LMR-240DB. Good luck buying a couple hundred feet. http://www.universal-radio.com/catalog/cable/coax.html See #2247. It's what dxAce uses! |
What Does "RG-6" {Coax Cable} Mean ?
dxAce wrote:
David wrote: RHF wrote: On Dec 31, 9:17 am, msg wrote: RHF wrote: snip Extra Protection* for the Buried Coax Cable can be obtained by using Half-Inch (1/2") Black Polyethylene Drip Water Tubing {Hose} as an added Layer of Protection for Buried Coax Cable against damage from Plants, Tree Roots and Animals. I have coax running through 1 1/2" PVC buried at 2 feet but be advised that you must provide a means of draining condensation or include desiccants or provide dry air flow to avoid water in your cables. In my case, I periodically blow out the pipe with compressed air and also have a 1 inch per foot grade to encourage drainage to one end where the water can then be extracted (blown out). Regards, Michael MSG - Good Advise. ~ RHF . Belden makes a Direct Burial RG-8X, 7808 I think. Times Microwave also has LMR-240DB. Good luck buying a couple hundred feet. http://www.universal-radio.com/catalog/cable/coax.html See #2247. It's what dxAce uses! Check the specs vs Belden 7808 or TM LMR-240 |
What Does "RG-6" {Coax Cable} Mean ?
David wrote: dxAce wrote: David wrote: RHF wrote: On Dec 31, 9:17 am, msg wrote: RHF wrote: snip Extra Protection* for the Buried Coax Cable can be obtained by using Half-Inch (1/2") Black Polyethylene Drip Water Tubing {Hose} as an added Layer of Protection for Buried Coax Cable against damage from Plants, Tree Roots and Animals. I have coax running through 1 1/2" PVC buried at 2 feet but be advised that you must provide a means of draining condensation or include desiccants or provide dry air flow to avoid water in your cables. In my case, I periodically blow out the pipe with compressed air and also have a 1 inch per foot grade to encourage drainage to one end where the water can then be extracted (blown out). Regards, Michael MSG - Good Advise. ~ RHF . Belden makes a Direct Burial RG-8X, 7808 I think. Times Microwave also has LMR-240DB. Good luck buying a couple hundred feet. http://www.universal-radio.com/catalog/cable/coax.html See #2247. It's what dxAce uses! Check the specs vs Belden 7808 or TM LMR-240 But that stuff isn't what dxAce uses! |
What Does "RG-6" {Coax Cable} Mean ?
dxAce wrote:
David wrote: RHF wrote: On Dec 31, 9:17 am, msg wrote: RHF wrote: snip Extra Protection* for the Buried Coax Cable can be obtained by using Half-Inch (1/2") Black Polyethylene Drip Water Tubing {Hose} as an added Layer of Protection for Buried Coax Cable against damage from Plants, Tree Roots and Animals. I have coax running through 1 1/2" PVC buried at 2 feet but be advised that you must provide a means of draining condensation or include desiccants or provide dry air flow to avoid water in your cables. In my case, I periodically blow out the pipe with compressed air and also have a 1 inch per foot grade to encourage drainage to one end where the water can then be extracted (blown out). Regards, Michael MSG - Good Advise. ~ RHF . Belden makes a Direct Burial RG-8X, 7808 I think. Times Microwave also has LMR-240DB. Good luck buying a couple hundred feet. http://www.universal-radio.com/catalog/cable/coax.html See #2247. It's what dxAce uses! How long is your run? |
RG-8X {50 Ohm} Coaxial Cable the Better Feed-in-lIne for ShortwaveRadio Listener (SWL) Antennas ?
On Dec 31, 12:03*pm, dxAce wrote:
David wrote: dxAce wrote: David wrote: RHF wrote: On Dec 31, 9:17 am, msg wrote: RHF wrote: snip Extra Protection* for the Buried Coax Cable can be obtained by using Half-Inch (1/2") Black Polyethylene Drip Water Tubing {Hose} as an added Layer of Protection for Buried Coax Cable against damage from Plants, Tree Roots and Animals. I have coax running through 1 1/2" PVC buried at 2 feet but be advised that you must provide a means of draining condensation or include desiccants or provide dry air flow to avoid water in your cables. *In my case, I periodically blow out the pipe with compressed air and also have a 1 inch per foot grade to encourage drainage to one end where the water can then be extracted (blown out). Regards, Michael MSG - Good Advise. ~ RHF *. Belden makes a Direct Burial RG-8X, 7808 I think. *Times Microwave also has LMR-240DB. *Good luck buying a couple hundred feet. - - - http://www.universal-radio.com/catalog/cable/coax.html - - - See #2247. It's what dxAce uses! - - Check the specs vs Belden 7808 or TM LMR-240 - But that stuff isn't what dxAce uses! RG-8X {50 Ohm} Coaxial Cable the Better Feed-in-lIne for Shortwave Radio Listener (SWL) Antennas ? OK - This Is The "Stuff" That 'DX Ace' Uses ! ~ RHF Universal-Radio P/N #2247 = RG-8X {Mini-8} Coaxial Cable http://www.universal-radio.com/catalog/cable/2247.html + Black - Non-Contaminating - Flexible Jacket. + Stranded Copper Center Conductor [16 AWG - 19sx29g] + Foam Dielectric + Braid Bare Copper Outer Conductor 98% Coverage + OD : 0.242" {Mini as in Small OD less than a 1/4"} -$- Price per Foot : 29¢ - That's a Low Price NOTE - Universal-Radio P/N #2247 RG-8X appears to be equivalent to Belden 9258 (RG-8X or Mini-8) Coax Cable. http://www.wehaveparts.com/pages/belden/9258.pdf Universal-Radio States : RG-8X is our most popular Coaxial Cable. It is a favorite for Shortwave Receiving Antennas. READY MADE CABLE ASSEMBLIES : Universal-Radio P/N #0515 - Pre-Assembled RG-8X Coaxial Cable http://www.universal-radio.com/catalog/cable/cable.html 100 Foot Length with PL-259 Plugs on both Ends Price : $29.95* -Note- Considering the 29¢ per Foot Price you get the Two PL-259 Plugs Installed - Sounds like a Deal to me. * This 100 Feet of RG-8X Coax Cable is a competitive Price with 100 Feet of Quad-Shield RG-6 Coax Cable at WalMart http://www.walmart.com/catalog/produ...uct_id=7811235 for $33 which is 33 Cents per Foot. MORE - Universal-Radio Coax Cable Info {Links} : http://www.universal-radio.com/catalog/cable/coax.html http://www.universal-radio.com/catal.../coaxperf.html http://www.universal-radio.com/catal...erf.html#atten INFO - More Info on RG-8X {Mini} Coax Cable http://www.bellscb.com/products/acce...RG-8X_coax.htm 9091 - http://www.therfc.com/coax.htm RG8X - http://www.davisrf.com/ham1/coax.htm 9258 - http://www.wehaveparts.com/pages/belden_cable.htm HOW TO - Fit a PL-259 Plug to RG8X Coaxial Cable. http://tinyurl.com/2w2vj7 eBay - Buying Belden Coax Cable - Beware ! -by- KC9EOA http://tinyurl.com/329nrt co ax ialy yours - iane and a short wave good bye ~ RHF {pomkia} |
RG-6 for HF?
In article ,
David wrote: Telamon wrote: In article , "Brian" wrote: I finally got a house out in the woods on five acres and I'm going to set up a couple of pretty long wires and my Wellbrook ALA-1530. I've pretty much decided on RG-6 for a couple of 150 ft. runs because the stuff's dirt cheap and I can pick it up at the local Home Depot. Is the impedance mismatch here going to be negligible, or should I just bite the bullet and go with RG-8 or a similar 50 ohm coax? I would not buy cable with the wrong impedance especially on the Wellbrook because I don't know how well the amplifier at the head end stands up to reflections. Some amplifiers become less stable into a load other than what it was designed for. Why don't you fire off that question to them. On the wire antennas you will take a hit on performance depending on frequency unless you use transformers on both ends. I'd give it a try. I doubt modern active devices will have any trouble with such a small difference. "I'd give it a try" is meaningless to me in this context because it is going to work. There is no question that it will work. What is in question is how well will it work. Here there would be no harm in "trying" if he already had the coax but he doesn't. He has to buy the coax and he may be able to save a few bucks. Then again he may not save any money. If the transmission line is not properly terminated on both ends then it will have resonances that may interfere with his reception. This is not much different than putting regular in a high compression engine that needs premium gas. The engine will still run OK it's just that you will not get the full performance that the engine can give you. -- Telamon Ventura, California |
Building a 75-to-50 Ohm [1.5:1] Matching Transformer for RG6 Coax Cable
In article ,
D Peter Maus wrote: Telamon wrote: In article , D Peter Maus wrote: RHF wrote: On Dec 30, 9:37 pm, D Peter Maus wrote: Brian wrote: I finally got a house out in the woods on five acres and I'm going to set up a couple of pretty long wires and my Wellbrook ALA-1530. I've pretty much decided on RG-6 for a couple of 150 ft. runs because the stuff's dirt cheap and I can pick it up at the local Home Depot. Is the impedance mismatch here going to be negligible, or should I just bite the bullet and go with RG-8 or a similar 50 ohm coax? -Brian - Alone, your receiver won't care. I doubt that the Wellbrook would, - either. - As a complex, however, you're going to have not one mismatch, - but - two. One at the output of the Wellbrook loop, and one at - the input - of - the antenna interface. This may result in standing waves on the - transmission line which, in turn may result in irregularities in - performance. - - With a reasonably well designed receiver, you'll likely not - notice - any losses in practical listening. And unless you are working at the - very limits of performance on signals very far down in the noise and - doing A/B tests of one coax over another, you'll not detect the - performance irregularities. - DPM, Then it becomes a Practical Implementation and CBA type Problem. CBA = Cost Benefit Analysis http://en.wikipedia.org/wiki/Cost-benefit_analysis http://en.wikipedia.org/wiki/Implementation Cost of RG58/RG8 Coax Cable -versus- Cost of RG6 Quad-Shield Coax Cable with a 75-to-50 Ohm Matching Transformer at each end. Starting with the Concept of a 9:1 Matching Transformer for General Broad-Band Shortwave Radio (High Frequency 3~30 MHz) Use and Application with 30 Turns (9-Side) and 10 Turns (1-Side) and the Same Ferrite Core Material : We now need a Matching Transformer to take the Antenna and Radios SO-239 Jack/Plugs {BNC Connector Optional} -to- the 75 Ohm Coax Cable with an F-Connector {BNC Connector Optional} . The 50 Ohm 10 Turns (1-Side) should be understood. Getting to the 75 Ohm (X-Side) should be simple Math : 75 / 50 = 1.5 Square Root of 1.5 = 1.225 Therefore the 75 Ohm (X-Side) would have 12 Turns. A 75 Ohm to 50 Ohm [1.5:1] Matching Transformer would have 12 Turns (1.5-Side) and 10 Turns (1-Side) and the Same Ferrite Core Material -as- 9:1 Matching Transformer for General Broad Band Shortwave Radio (High Frequency 3~30 MHz) Use and Application. Anyone Else Have Any Ideas : On a Building Your Own {DIY} a 75 Ohm to 50 Ohm [1.5:1] Matching Transformer ? - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - The Next Question Becomes : At What Cost ? * Are the 75 Ohm to 50 Ohm [1.5:1] Matching Transformers commercial available ? - a Ready Made Item ? Price ? * Are the 75 Ohm to 50 Ohm [1.5:1] Matching Transformers a Low Cost "Built-it-Yourself" Item ? - DIY Price ? - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - DPM - I go back to your first statement : "Alone, your receiver won't care. I doubt that the Wellbrook would, either." IMHO - For the vast majority of Shortwave Radio Listeners (SWLs) Practical Implementation Says : Just Do It ! - Use the RG6 Coax Cable -and- enjoy listening to your radios - iane ~ RHF . Which was precisely my point. It's dumb to buy cable or anything else that is not matched to the task unless there is some kind of over riding factor such as cost. In your universe, and mine, yeah, you buy the best, brightest, matched, optimized, or NFL approved. Truth is, that in real world operations within the normal parameters hobbyists achieve, there is likely no detectable difference between the 'correct' choice, and the most economical choice for transmission line in this application. And given that the OP was concerned about cost, his choice is a decent one. And unless the OP is intending to operate his system at the limits of performance, any losses incurred will not be relevant to his operation. Would I do it that way? No. Would you do it that way? I'm thinking not. But we're in a different position to make these decisions. And we both have the hardware to not only notice the difference in antenna/transmission line performance, but we operate closer to the limits than the OP. For you and me, the choice of coax may well make a detectable difference. In my case, it would also bother me to install a line that I knew wasn't correct for the application. There are others here with the same attention to detail. And still others who will not hear or detect the differences. You're running RX-340. The minutiae at the antenna can be heard. It's not the case when the best receiver you've ever encountered is Sat-800. Well, yes performance is a critical parameter but I would not frame the discussion around a high performance radio. The radio I own is not the issue as ANY table top radio will be adversely affected in reception performance. The performance issue that will affect ANY radio is due to a recombination of forward and reflected waves that run the gamut of reinforcement to cancelation. Where reinforcement or cancelation of incoming signals will occur will depend on several factors and as a consequence not easy to calculate. You may not ever hear a signal on some frequency because that is where the cancelation occurs. The cancelation has to happen somewhere in the frequency band. If you never listen to that spot or spots then no problem but if it happens where you want listen then tough luck. The general rule in a broad band system is to have components matched in order to prevent these complex results of significant reflections. I'll state again that if you already own the coax to try it, especially if you only have interest in certain frequencies or have another radio and antenna to check propagation. If it works where you want to listen then that's just fine but buy the wrong coax? I would not recommend that. -- Telamon Ventura, California |
Building a 75-to-50 Ohm [1.5:1] Matching Transformer for RG6Coax Cable
Telamon wrote:
In article , D Peter Maus wrote: Telamon wrote: In article , D Peter Maus wrote: RHF wrote: On Dec 30, 9:37 pm, D Peter Maus wrote: Brian wrote: I finally got a house out in the woods on five acres and I'm going to set up a couple of pretty long wires and my Wellbrook ALA-1530. I've pretty much decided on RG-6 for a couple of 150 ft. runs because the stuff's dirt cheap and I can pick it up at the local Home Depot. Is the impedance mismatch here going to be negligible, or should I just bite the bullet and go with RG-8 or a similar 50 ohm coax? -Brian - Alone, your receiver won't care. I doubt that the Wellbrook would, - either. - As a complex, however, you're going to have not one mismatch, - but - two. One at the output of the Wellbrook loop, and one at - the input - of - the antenna interface. This may result in standing waves on the - transmission line which, in turn may result in irregularities in - performance. - - With a reasonably well designed receiver, you'll likely not - notice - any losses in practical listening. And unless you are working at the - very limits of performance on signals very far down in the noise and - doing A/B tests of one coax over another, you'll not detect the - performance irregularities. - DPM, Then it becomes a Practical Implementation and CBA type Problem. CBA = Cost Benefit Analysis http://en.wikipedia.org/wiki/Cost-benefit_analysis http://en.wikipedia.org/wiki/Implementation Cost of RG58/RG8 Coax Cable -versus- Cost of RG6 Quad-Shield Coax Cable with a 75-to-50 Ohm Matching Transformer at each end. Starting with the Concept of a 9:1 Matching Transformer for General Broad-Band Shortwave Radio (High Frequency 3~30 MHz) Use and Application with 30 Turns (9-Side) and 10 Turns (1-Side) and the Same Ferrite Core Material : We now need a Matching Transformer to take the Antenna and Radios SO-239 Jack/Plugs {BNC Connector Optional} -to- the 75 Ohm Coax Cable with an F-Connector {BNC Connector Optional} . The 50 Ohm 10 Turns (1-Side) should be understood. Getting to the 75 Ohm (X-Side) should be simple Math : 75 / 50 = 1.5 Square Root of 1.5 = 1.225 Therefore the 75 Ohm (X-Side) would have 12 Turns. A 75 Ohm to 50 Ohm [1.5:1] Matching Transformer would have 12 Turns (1.5-Side) and 10 Turns (1-Side) and the Same Ferrite Core Material -as- 9:1 Matching Transformer for General Broad Band Shortwave Radio (High Frequency 3~30 MHz) Use and Application. Anyone Else Have Any Ideas : On a Building Your Own {DIY} a 75 Ohm to 50 Ohm [1.5:1] Matching Transformer ? - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - The Next Question Becomes : At What Cost ? * Are the 75 Ohm to 50 Ohm [1.5:1] Matching Transformers commercial available ? - a Ready Made Item ? Price ? * Are the 75 Ohm to 50 Ohm [1.5:1] Matching Transformers a Low Cost "Built-it-Yourself" Item ? - DIY Price ? - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - DPM - I go back to your first statement : "Alone, your receiver won't care. I doubt that the Wellbrook would, either." IMHO - For the vast majority of Shortwave Radio Listeners (SWLs) Practical Implementation Says : Just Do It ! - Use the RG6 Coax Cable -and- enjoy listening to your radios - iane ~ RHF . Which was precisely my point. It's dumb to buy cable or anything else that is not matched to the task unless there is some kind of over riding factor such as cost. In your universe, and mine, yeah, you buy the best, brightest, matched, optimized, or NFL approved. Truth is, that in real world operations within the normal parameters hobbyists achieve, there is likely no detectable difference between the 'correct' choice, and the most economical choice for transmission line in this application. And given that the OP was concerned about cost, his choice is a decent one. And unless the OP is intending to operate his system at the limits of performance, any losses incurred will not be relevant to his operation. Would I do it that way? No. Would you do it that way? I'm thinking not. But we're in a different position to make these decisions. And we both have the hardware to not only notice the difference in antenna/transmission line performance, but we operate closer to the limits than the OP. For you and me, the choice of coax may well make a detectable difference. In my case, it would also bother me to install a line that I knew wasn't correct for the application. There are others here with the same attention to detail. And still others who will not hear or detect the differences. You're running RX-340. The minutiae at the antenna can be heard. It's not the case when the best receiver you've ever encountered is Sat-800. Well, yes performance is a critical parameter but I would not frame the discussion around a high performance radio. The radio I own is not the issue as ANY table top radio will be adversely affected in reception performance. The performance issue that will affect ANY radio is due to a recombination of forward and reflected waves that run the gamut of reinforcement to cancelation. Where reinforcement or cancelation of incoming signals will occur will depend on several factors and as a consequence not easy to calculate. You may not ever hear a signal on some frequency because that is where the cancelation occurs. The cancelation has to happen somewhere in the frequency band. If you never listen to that spot or spots then no problem but if it happens where you want listen then tough luck. Not every receiver will detect such cancellations at this operating level, and with this magnitude of mismatch. Noise floor, location and ambient noise will render some antenna losses irrelevant in practical listening, and depening on frequency. If you're not working at the limits of performance, small mismatches in a receiving transmission line are trivial. We're not talking about military grade monitoring of picowatt signals, here. The general rule in a broad band system is to have components matched in order to prevent these complex results of significant reflections. I'll state again that if you already own the coax to try it, especially if you only have interest in certain frequencies or have another radio and antenna to check propagation. If it works where you want to listen then that's just fine but buy the wrong coax? I would not recommend that. Sometimes, the economics ARE the issue. |
Building a 75-to-50 Ohm [1.5:1] Matching Transformer for RG6 CoaxCable
On Jan 3, 9:21*pm, Telamon
wrote: In article , *D Peter Maus wrote: Telamon wrote: In article , *D Peter Maus wrote: Telamon wrote: In article , *D Peter Maus wrote: RHF wrote: On Dec 30, 9:37 pm, D Peter Maus wrote: Brian wrote: I finally got a house out in the woods on five acres and I'm going to set up a couple of pretty long wires and my Wellbrook ALA-1530. I've pretty much decided on RG-6 for a couple of 150 ft. runs because the stuff's dirt cheap and I can pick it up at the local Home Depot. Is the impedance mismatch here going to be negligible, or should I just bite the bullet and go with RG-8 or a similar 50 ohm coax? -Brian - *Alone, your receiver won't care. I doubt that the Wellbrook would, - either. - As a complex, however, you're going to have not one mismatch, - but - two. One at the output of the Wellbrook loop, and one at - the input - of - the antenna interface. This may result in standing waves on the - transmission line which, in turn may result in irregularities in - performance. - - With a reasonably well designed receiver, you'll likely not - notice - any losses in practical listening. And unless you are working at the - very limits of performance on signals very far down in the noise and - doing A/B tests of one coax over another, you'll not detect the - performance irregularities. - DPM, Then it becomes a Practical Implementation and CBA type Problem. CBA = Cost Benefit Analysis http://en.wikipedia.org/wiki/Cost-benefit_analysis http://en.wikipedia.org/wiki/Implementation Cost of RG58/RG8 Coax Cable -versus- Cost of RG6 Quad-Shield Coax Cable with a 75-to-50 Ohm Matching Transformer at each end. Starting with the Concept of a 9:1 Matching Transformer for General Broad-Band Shortwave Radio (High Frequency 3~30 MHz) Use and Application with 30 Turns (9-Side) and 10 Turns (1-Side) and the Same Ferrite Core Material : We now need a Matching Transformer to take the Antenna and Radios SO-239 Jack/Plugs {BNC Connector Optional} -to- the 75 Ohm Coax Cable with an F-Connector {BNC Connector Optional} . The 50 Ohm 10 Turns (1-Side) should be understood. Getting to the 75 Ohm (X-Side) should be simple Math : 75 / 50 = 1.5 Square Root of 1.5 = 1.225 Therefore the 75 Ohm (X-Side) would have 12 Turns. A 75 Ohm to 50 Ohm [1.5:1] Matching Transformer would have 12 Turns (1.5-Side) and 10 Turns (1-Side) and the Same Ferrite Core Material -as- 9:1 Matching Transformer for General Broad Band Shortwave Radio (High Frequency 3~30 MHz) Use and Application. Anyone Else Have Any Ideas : On a Building Your Own {DIY} a 75 Ohm to 50 Ohm [1.5:1] Matching Transformer ? - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - The Next Question Becomes : At What Cost ? * Are the 75 Ohm to 50 Ohm [1.5:1] Matching Transformers commercial available ? - a Ready Made Item ? Price ? * Are the 75 Ohm to 50 Ohm [1.5:1] Matching Transformers a Low Cost "Built-it-Yourself" Item ? - DIY Price ? - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - DPM - I go back to your first statement : "Alone, your receiver won't care. I doubt that the Wellbrook would, either." IMHO - For the vast majority of Shortwave Radio Listeners (SWLs) Practical Implementation Says : Just Do It ! - Use the RG6 Coax Cable -and- enjoy listening to your radios - iane ~ RHF *. * *Which was precisely my point. It's dumb to buy cable or anything else that is not matched to the task unless there is some kind of over riding factor such as cost. * *In your universe, and mine, yeah, you buy the best, brightest, matched, optimized, or NFL approved. * *Truth is, that in real world operations within the normal parameters hobbyists achieve, there is likely no detectable difference between the 'correct' choice, *and the most economical choice for transmission line in this application. And given that the OP was concerned about cost, his choice is a decent one. * *And unless the OP is intending to operate his system at the limits of performance, any losses incurred will not be relevant to his operation. |
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