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I forgot to say, the only antenna using rg6u quad shield is my vertical. the rest is using ladderline. I have a simple balun to help match impedances and my simple match unit i built. 73 David ac9xh
On Friday, August 5, 2022 at 05:57:31 PM EDT, david todd via groups.io <ac9xh@...> wrote:
I used to use an ammeter and a neon bulb. tune to max on both. Also,It helps to cut the antenna to band resonance. I have several antennas ,one for each band i run, also i use a homebrew vertical 3 ft above ground with no radials and this one is the one i use? from 80 to 6 meters. i actually have to use my homebrew match for it. All my antennas have been cut for band resonance, i dont use a commercial match except for my ubitx v6 which i installed inside of it.. For my other ubitxs and bitxsi use a homebrew match using 15 turns of #22 gauge wire with a 100 pf variable? to help match to the antenna and a $5 dollar swr meter inline. Ive used this setup for all my radios, and including ubitx v3,v6,bitx40, patcomm pc 500, argonaut 509,. Sometimes, if your antenna is crappy or not designed properly, or have feedline problems etc ,you can"tune" the "antenna tuner and receive almost a 1:1 and never get out very well because of the false sense of security with an antenna tuner. I dont like the term tuner We all use, because you are not tuning the antenna,but just creating a compatible match from radio to cable. You might check your coax,fittings and antenna connections. With an open circuit(break in the coax at the fitting or antenna)you will take awhile to get any match impedance wise. If you have an auto antenna match, and it starts clicking for over 6 to 14 seconds, more than likely an open somewhere or a really big problem with your antenna, .I personally experienced this with the ldg z100. had a cable break right at the fitting. Just my personal take of it all. And i have never popped a final on any of my ubitxs or bitxs. 73 David ac9xh
On Wednesday, August 3, 2022 at 03:09:45 PM EDT, Jerry Gaffke via groups.io <jgaffke@...> wrote:
Here is one of many posts from Allison that are worth reviewing, mentions the 6m 225W power amp she built using 4+4 IRF510's in push-pull. The whole thread is worth a read. ??/g/BITX20/message/22597 She has been contributing to the forum for some time now: ??/g/BITX20/message/14514 ??/g/BITX20/message/869 Just plugging a new fet into the sBitx likely won't solve anything. The circuit around it should be designed specifically for that part for good performance. Jerry, KE7ER On Wed, Aug 3, 2022 at 10:14 AM, Jerry Gaffke wrote: The IRF510 can work dependably, Allison reports years of success with HF amps at 40W push-pull, |
