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That counter can be a hair-puller when it breaks. It takes the 8 Volt regulator output and passes it through a 3-Volt zener diode to supply the 5-Volt chips. We got in the habit of taking a 3-terminal TO-220 7805T regulator and placing it face down with the input and output pins in the holes...

The meter that was used to obtain the numbers in the Heath manual would have been one of their VTVM models, most likely. Used a 1.5-Volt flashlight cell to power the Ohms scale. You need a meter that uses DC to measure resistance when comparing to the manual's numbers. Worn-out front-panel...

Our answer to the ground loop problem is to connect a .001uf disc cap from the coax shield to the circuit board ground near the synthesizer circuit. This grounds the braid for the RF circuit, and blocks any DC-ground loop issues. Very cool! Which DDS did you use? The 985x or the 5351? 73

20 Watts of carrier per transistor shouldn't be out of reason at all. 73

Like restoring a '63 Vette that's been at the bottom of a creek for 20 years. And you'll have to come up with your own circuit diagram unless there's one hiding inside it. 73

Found on Scribd. 73

Home brew. The Dymo label tape is a hint. 73

Sales hype. If he wants 800 Watts he needs eight of those, not four. 73

Here's the schemo for the "old" version, without the string of NightRider lights along the bottom. Should be similar. 73

Here's Motorola's original specs. They call it a 100-Watt PEP part. Your builder is recommending twice that from four parts. Maybe he wants you to blow it up and come back for another one? Soon? 73

Age and mileage both matter. Not all capacitors are created equal. Wish I had a database of which brands survive longest on the shelf. I have unloaded my share of decades-old electrolytics on fleabay, either because they were types we'll never use, or because they were just too old to risk...

Skipp has aggregated just about everything ever written about the 1011 radios that's worth seeing. I swore off repairing them and unloaded all our parts radios a while back. Still haven't regretted it. 73

Hmm. A la Dunning Krueger? Feel free to wiki it if it doesn't sound familiar. 73

Nextel reincarnated. 'bout time. 73

Sounds like a good spot to avoid. 73

What is it the young folks say? "Pics or it didn't happen". This crystal's lead wires did rot away because of the brown glue holding this crystal to the pc board. New crystal made this Cobra 25GTL a lot happier. Made sure to scrape away all signs of this stuff. 73

The brown glue is bad juju. Gets corrosive eventually. Best to find every spot where it was used and scrape it off. Denatured alcohol will soften it, or 99% isopropyl. The advantage of using alcohol as a solvent is that it can't attack any plastic materials in the radio. Is there a chunk of...

Here's the followup to the Mark 4A receiver crystal substitute mod. The Browning Mark 3 receiver is an older dog than the Mark 4/4A. Does use a crystal for each tuneable band. The first version from 1970 had only one tuneable band and two fixed-crystal channels. The one and only band crystal...

Never forget the rule of the Shadetree Mechanic: If it ain't broke, keep fixing it until it is. A radio with zero miles probably functions just fine. I'd wait to worry about caps until it exhibits a fault. My experience has been that once the first one or two caps goes bad, the falling dominoes...

Those two added parts are what make the AM limit in other models adjustable. Just left them out of this model. 73