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Yeah, we were a little harsh on the new guy... :unsure: Chainsaw660, maybe you could do some preliminary tests like check the voltages on the AM regulator/modulator with the radio keyed and also see if you can set the idle bias on the driver and final.

He mentioned that the meter light goes out when it's unkeyed. Being as the light gets voltage from the same switched source as the bias supply, I doubt the bias supply is staying on.

One of these will fix it so it never needs fixing again. Most reliable tool on any tech bench. ;) Joking of course.. Can you hear it transmitting on a radio sitting next to it on the bench?

Yeah..

I've seen before where the normally open side of the input contact of the relay gets shorted closed even though the contacts are unkeyed. This causes the base bias supply to turn on heating the transistors up. When this happens the meter light stays on whenever the power switch is on. If the...

It's a "46" style cap. Looking at the zoomed in pic it looks like it only has one mica layer so it's value is very low. It's probably like 5-30pf or 10-50pf, something like that.

Thanks @Marconi :D

I believe the "12 volt" TRW devices were specified at 13.5V. Yes, there aren't many TRW datasheets floating around on the net these days. I'm just going by memory as I'm an old fart and dealt with these parts a lot when they were being used. I used to have many of the datasheets back in the late...

Most of the older amps that had TRW transistors used the PT9847 (80 watt 30Mhz) device. The smaller 2 pill boxes used either the stud or flange mount PT9784 (60 or 75 watt 30Mhz depending on the datasheet). The Hercules was the only CB amp I've ever seen that used the robust PT9849 (100 watt...

At 11 meters, a wirewound higher than 1 ohm would start having significant inductance as the resistance wire is spiral wound. I'd recommend using carbon or metal film only, especially for a combiner/splitter. If a guy wants a 10 watt device there, specifically order non-inductive wirewound.

Are those white brick resistors non-inductive wirewound?

The old Scotch-Master https://www.cbtricks.com/ant_manuals/mosley/a_511_s/ad/index.htm

The emitter of TR-20

Welcome back!

I guess this thread is as good as any to add something I found out years ago. The top fiberglass whip on the Shakespeare - Super Bigstick also has three straight wires inside that are silver or at least silver plated. Here in 2022 a guy doesn't see one very often as they were either overpowered...

Is it a newer front-mic version?

To get a little more gain on the mic preamp, change the bootstrap cap C63 to a .22uF 50V or higher. Need a little more? Change R62 to a 100K, 1 watt.

Purty!

The original Skipshooters made in Hermiston, Oregon have a straight brass rod at the top with no head.

Smiley at Smiley CB in Cali was sent a sample of it as well with the promise it was gonna be the new best thing soon. I'm pretty sure the finished product never materialized.