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Here's the breezy version of extra transmit channels for the Browning Mark 4A transmitter. Not the Mark 4. Different transmitter altogether. This setup requires two toggle switches and wire. One DPDT on-on switch and a SPST switch. Or any substitute. The focus of this trick is nine...

Revisions continue for this idea. We have used four 1N5408 rectifiers to replace the Mark 4A 4-legged bridge "block". Had too many of the factory bridge cause a headache after a repair. But simplifying the labor for this procedure is probably a good idea, so this list now starts with a one-piece...

Mostly I avoid making negative statements about a particular product. I'll just channel grandma to describe the 350Z. She said "If you can't say anything good, don't say anything. " Besides that we won't fix one. 73

Has to be a broken wire connection between the channel selector and the PLL chip. Or maybe a solder bridge between two of those wires? 73

Gotta figure it's in the thousands. But if the transistor's unit cost is well under a buck, it's worth somebody's while to do. Now that everybody uses laser etching instead of ink it has to be easier than ever to buy what they used to call a "house number" part. 73

Most amplifiers are not directly compatible with a stock legal 40-channel CB. The amplifier tends to exaggerate the carrier, and limit the audio peaks. There are two ways to fix it. One is to turn down the amplifier if it has a High/Low or H/M/L switch. This is the cheap fix, but not so popular...

Ah, "both"? It came with one fusholder on the rear of the RF deck. We adopted the habit of putting a 15 Amp fuse in a holder on the power transformer to protect the low-voltage winding. Found that a short on the 12 Volts alone might not trip the AC fuse in time to protect the 12-Volt winding...

The speaker amp chip has nothing at all to do with AM transmit audio. Another job for a cheap outdated o'scope. Seeing is believing. 73

It was Uniden's captive brand back in the day. 73

What I mean by false peak is the behavior of the tuning slug. It reaches the rim of the opening and appears to exhibit a peak because turning it further reduces inductance as the slug rises above the rim. Max inductance gets you closest to resonance without reaching it. Max inductance is...

Didn't change C9? Its directly between the chip's output on pin 9 and the speaker. A 'scope would reveal at a glance if that were causing trouble, just comparing what goes into it with what comes out of it. 73

I think we have one that got converted to use as a VFO on Browning base-station transmitters. Wasn't a good conversion, but that part of it still worked last time I powered it up. Just doesn't drive the Browning hard enough. Can't sell them on fleabay. Always get a nastygram that it's not...

I'm certainly ready for Alan to make the Browning-only parts available again. Greg Barkett stopped selling the day he got paid to close out that stuff. Alan didn't purchase the e-commerce site nor the database that goes with it. Getting it all listed online will take some effort. Just glad I...

So here's another idea that hasn't quite graduated to half-baked. More like half defrosted. Back in the day, if the hired help had a slow day, he would put together parts kits for rehabbing the tube CB radios. The pieces they would need is predictable up to a point. But there is always a fixed...

The six digits are multiplexed. If you hold a fan between your eyes and the display, you'll see a strobe pulsation as the fan blades spin. Only one digit is powered at a time. The individual segments are all wired in parallel. The "a" segment of all six digits are wired together, and so on for...

To turn a "2" into a "6" the a segment has to be shut off when it should be on and the e segment turned on when it should be off. All the later frequency displays wire the digits in an altogether different format from that one. Just not remotely compatible with the display wiring in a pre-1995...

The side-by-side 3-pin headers have the PTT pins tied from one header to the other. The echo board just passes the PTT line from the mike socket through the echo board to the main pc board. It's not connected inside the echo board. A digital echo, however is different. The PTT line will serve...

Never underestimate the power of resonance. 73

I remember a test setup from decades ago that switched a fixed capacitor in parallel with the IF transformer winding. This tester was an oscillator circuit, and the change in frequency could be used to calculate the value of a transformer's internal capacitor. This is a spec you never see on a...

I sympathize. The alternative is to "audit" the assembly and compare every part to the correct type. Not efficient. But maybe a little less inefficient than finding a 'wrong' part the hard way. 73