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A resistor that's "quieter" may improve a circuit that handles very small signals. But in a power amplifier with large signal voltages you'll have no way to tell the difference. A capacitor with lower eqivalent series resistance will make some circuits work better. But other circuits won't...

I helped screen new-member signups on the old cbtricks forum years ago. It was relentless. Ten or twenty obvious bogus signups for every one legit member. It never ends. 73

Just don't sell him anything. Horror stories abound. 73

The Toshiba transistors were in production for decades. This product lifespan is a lot longer than many semiconductor products. It was normal in the 1980s for a transistor to get discontinued after only a few years. A new improved part would take its place. The result of a long production life...

Umm, what kind of amplifier? 73

Now you know why I quit trying to troubleshoot oscillators with a frequency counter. Just not sensitive enough. Tried using a preamp with a scope probe feeding it, but it was twitchy when the signal level was high enough to overdrive it and make it produce harmonics. A receiver calibrated for...

The Galaxy 1000 in this diagram is definitely different on the inside from your 600. But there's a family resemblance. Just to start, the tubes have 6.3-Volt heaters in parallel on this diagram. Yours apparently has the tube heaters wired in series to power directly from the 120-Volt line. What...

I would start with testing the tubes. More than one way to get this fault, but the tubes can fail and cause this. There's a post up above asking about the tube's "cathode fuse". No, it's not meant to be a fuse, just acts like one. Operating at high power with the output tuned wrong seems to be...

Ya found that quick! Rock on! 73

Can't remember if the out-of-lock detector is high or low when locked. Pretty sure it's high. If you haven't pulled up that line coming from the original PLL the transmit will shut down as if the PLL were unlocked, even though your source of local-oscillator input to the mixers isn't coming...

So, this is what we often see when coil slugs have been tweaked, one by one until they're all at random settings. The tweaker finally sees the wattmeter move a little and then gives up. The way the Mark 3 mixes three oscillators to get the channel frequency leaves open a lot of tuning slugs to...

T1 is the "whine" choke, meant to reduce noise from a vehicle's alternator. The mobile 140GTL model has this, the base 142 radio does not. Sounds like your trimpot is VR12, the modulation meter calibrate pot. That's what the 142 schematic suggests, since the mobile 140 doesn't have a...

Lordy.. Measure twice, cut once. My pinouts above may be wrong. I may have numbered them out of sync by one letter. The upper-right segment should be "a", the lower right "b", the bottom segment "c" and on clockwise to the top "f". Center segment is "g". Looks like I started with the top...

Here is a pinout we reverse-engineered with a power supply, resistors and gator leads. . This is a top-side view, not the usual bottom-side pinout you would see on a legit data sheet. The one on the top is the original three-digit 0.56-inch stick that came on the PLJ counter board. We removed...

I may have a part number at work. We use a pair of three-digit common-anode sticks like this. The character height is a big deal. They sell 0.28, 0.36 and 0.4 inch three-digit sticks. Pretty sure they don't easily intermix. We have some 0.36 we use for a 6-digit counter display that fits in the...

Quick test to see if the final and driver transistor both have enough bias current with no drive. Clarify the radio's signal on a second radio. Turn down the mike gain on the test radio until the peak power is below 2 Watts. If it sounds gritty this way and clears up at higher power levels...

Rather than reconnect the old capacitor, I'd just replace C114 the 47 uf cap that has the positive side on pin 10 and the negative side on pin 9. Use a 25-Volt or higher-rated part. The original is probably marked 10 Volts. If you have one, of course. And maybe someone unhooked it pursuing...

Just noticed you said "Gee Tee Ell". That makes the radio 40 years old or more, pretty sure. If the radio has a lot of miles on it, might be time to replace all the electrolytic caps. That kind of component is built from materials that predictably degrade from age alone. And if it's used a lot...

Hey, you're getting there. Fixing a sabotage radio tends to have hairpin turns, switchbacks and blind corners. Does bring to mind the old saw "More issues than National Geographic". Or maybe "Rougher than a stucco bathtub". Just hope the relay is okay. The MX3P is one relay I probably won't...

Check bias diodes on the driver and finals. And the bias trimpots. 73