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Yesterday I was checking dc voltages as listed in Sams and so far everything checks out. I have a dummy load connected to the 458 and when I would key it up, the radio I was listening to dx on was picking up the signal, from about a foot away, so it's putting something out. My rf probe showed up...

Power supply is fixed. I checked all the voltages shown in the Sams schematic and found 6.16v instead of 15.06v at the base of TR302. I pulled and checked TR302, TR301, RT301, and R304. All checked fine. On a hunch, I lifted a leg of C410 and the capacitor check on my meter couldn't get a...

I do have an external power supply and several good working radios so that's not a problem. I'm going to build an rf probe for my multimeter, been wanting to for a while anyway, and when Sams CB#207 shows up I can do some probing and maybe get a better grip on this thing. I do want to get the...

Figured you meant RT301 and adjusting it made very little difference and actually the lowest voltage I see, right at 17v, is about dead center. Clockwise brings it up to maybe 17.5, counterclockwise never gets it below 17v. I went in small increments both ways after noting my starting point and...

I figured as much. Thanks! 8.14V When I initially went to take voltage readings, I had my negative test lead connected to the chassis but was getting way wrong voltages. I connected the negative lead to a known ground on the board and got accurate readings. Is the chassis not grounded? I also...

Thanks for that. TR24 on tx Collector 13.68v Base 9.08v Emitter 8.14v I also checked the voltage at my power supply and it's right at 17 volts. I feel like that's high and should be closer to 13.8?

I forgot to mention D28 and R112 got hot enough to start melting the insulation covering the long wire leads. I pulled R112 and it tested fine, haven't tested D28 yet. Also tantalum C188 got hot enough too scar C183 and L33 on either side. Hot enough to be an issue? Bonus points for the broken...

I ended up with two TRC-458s in a trade. One worked and the other had been hacked on pretty bad, probably be good for parts. Knowing they both have original caps, I rolled the dice and started using the one that works. A few days in I heard a bit of a hum and figured it was outside interference...

My first recap almost finished.

I personally don't care for linked GMRS repeaters. There is a large linked private network in my area and they've had up to three channels (channelized service so I'm calling them channels) monopolized at the same time on several occasions rendering all other local repeaters on the same channels...

DX is hopping near St Louis right now. A half hour sitting in my Jeep on the barefoot McKinley has netted the most contacts I've ever made.

I see it referred to as a 1:1 coax loop balun elsewhere. 1/4 wave and 3/4 wave sections, VF corrected.

This is the one I used. It's been spot on so far. Used it on simplex and the usual repeaters with great results. Haven't been able to get it in the air yet, tested on a camera tripod. https://3g-aerial.biz/en/online-calculations/antenna-calculations/dl6wu-yagi-uda-antenna-online-calculator

A little fun with some 8awg ground wire and a (surprisingly straight) 1/2 x 3/4" furring strip. Swept well and works great. I call it Jacob's Ladder.

Oh man thanks, great info and I appreciate you taking time to post that. Impedance and SWR was initailly balun only into 50 ohm load with impedance around 45-46 ohms and SWR 1.25 and once assembled with antenna, pretty close to the same results. I may be calling it a 1:1 balun mistakenly. Here...

A little more research leads me to think that wasn't the correct way to test the balun. The antenna works great though. I'm building a 12 element now and I'm just going to use the calculated measurements and see how it works. If anyone can give me insight on how to properly test a 1:1 UHF coax...

Well I cut all that extra shield off that I twisted together as i imagine that skews something, connected a 50 ohm load (that's used for calibrating my vna) across the feed and ended up snipping about 1/8" off the 1/4 wave section and about 3/8"off the 3/4 section. Got it real close to 50 ohms...

I figured it out. Best antenna I've made so far.

I'm going to start experimenting with GMRS Yagis and so now I'm building my first balun ever. The plan I'm using calls for a 1:1 coax balun using a 1/4 and 3/4 wave sections. Am I correct that I can connect a 50 ohm load across the leads and check impedance on my nanovna and adjust? I went ahead...