Re: Topband: TV coax + F-connectors
On 2/21/2022 3:28 AM, Rob Atkinson wrote: I'm already deaf and don't need for it to be any worse than it is. Loss in coax is not an issue if we're limited by RX noise. It only matters when where we live is very quiet. I use Commscope flooded RG6 extensively for RX antennas from 160 up to UHF TV. And for FM and UHF TV, I have a preamp and the antennas. 73, Jim K9YC _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: TV coax + F-connectors
Good luck with that voltage breakdown rating for foam RG6 running high power through it and other than a flat line. As to the milliwatt loss on transmit, okay FB but on rx with microvolts, I'm already deaf and don't need for it to be any worse than it is. 73 Rob K5UJ _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: TV coax + F-connectors
On 2/20/2022 7:46 AM, Radio KH6O wrote: Reading the comments about possible lack of uniform impedance and other short-comings, I remind myself that I'm an amateur, not a professional. A few milliwatts loss doesn't concern me. 73, Jeff KH6O _ The issue of non-uniform impedance and VF vs frequency is not one of "amateur vs professional", but rather simple antennas vs phased arrays. Junky coax can noticeably mess up the array pattern. 73 Rick N6RK _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: TV coax + F-connectors
On Sun, Feb 20, 2022, 2:55 PM Jim Brown wrote: > On 2/20/2022 10:53 AM, Mike Waters wrote: > > And RG-6 has a power handling curve very similar to RG-213. > > WRONG! This may be true of SOME RG6 cables, but definitely NOT true of > many. > Point well taken, Jim! I actually use a couple different types of Commscope F-6, bonded aluminum foil with braid(s). 73 Mike W0BTU > _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: TV coax + F-connectors
On 2/20/2022 10:53 AM, Mike Waters wrote: And RG-6 has a power handling curve very similar to RG-213. WRONG! This may be true of SOME RG6 cables, but definitely NOT true of many. For at least 50 years, RG numbers have not been a spec, but rather a general description defining impedance and approximate outer diameter. There are hundreds of RG6 cables, many of them quite different from each other, and there are many different connectors. There are 63 "RG6 type" cables in what is probably the last printed version of Belden's catalog (from 2006). The vast majority of RG6-type cables are made for MATV and CATV applications, with copper-coated steel centers and Al foil/braid shields, and the number of those braids and foils varies from one to four. There's at least one RG6 in the Belden catalog with a solid copper center and a double copper braid shield. I have some of a Pasternak-branded cable that appears to be built to that spec, and I suspect it was for analog video inside studios. I also have about 500 ft of a very similar Belden RG11, also designed for analog video. 73, Jim K9YC _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: TV coax + F-connectors
I can testify that F connectors with RG-6 will handle the legal limit on at least 160 and 80 without even getting warm. This is true here with 2500 watts into a dummy load and CW contesting. I waterproof mine by partially filling them with silicone dielectric grease. Been doing that here for many years without a single problem. Outdoors, I use waterproof F connectors. If you use RG-6, the rough points on the center conductor should be filed smooth with a small fine file. Otherwise, the contacts in the male receptacle can be damaged. And RG-6 has a power handling curve very similar to RG-213. 73 Mike W0BTU _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: TV coax + F-connectors
Greetings. I do not know if they still do use them. But the MAJOR Amateur AND PROFESSIONAL antenna maker M Squared uses "F" connectors in their antennas ALL the time. They even use a variation that is weatherproof. They use them from below 1 meg antennas up to antennas in the Gig ranges. Mainly at the feedpoint to connect the phasing line in the 4 to 1 balun feed design. Joe WB9SBD / W9ET On 2/20/2022 9:46 AM, Radio KH6O wrote: Colleagues, I was very happy to see the discussion regarding the use of television feedline and F-connectors. I thought I was the only ham in the universe using that combination. While it's true that the connectors are not weather-resistance, a coating of black asphalt sealant* takes care of that. Reading the comments about possible lack of uniform impedance and other short-comings, I remind myself that I'm an amateur, not a professional. A few milliwatts loss doesn't concern me. * For example:https://www.lowes.com/pd/Henry-Company-Asphalt-Emulsion-1-Gallon-Waterproofer-Roof-Sealant/50255565 73, Jeff KH6O _ Searchable Archives:http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Topband: TV coax + F-connectors
Colleagues, I was very happy to see the discussion regarding the use of television feedline and F-connectors. I thought I was the only ham in the universe using that combination. While it's true that the connectors are not weather-resistance, a coating of black asphalt sealant* takes care of that. Reading the comments about possible lack of uniform impedance and other short-comings, I remind myself that I'm an amateur, not a professional. A few milliwatts loss doesn't concern me. * For example: https://www.lowes.com/pd/Henry-Company-Asphalt-Emulsion-1-Gallon-Waterproofer-Roof-Sealant/50255565 73, Jeff KH6O _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
