Dave Hockaday WB4IUY, Youngsville NC USA FM05
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The WB4IUY Workshop

Engineering Projects @ WB4IUY/AC4QD

I really enjoy repairing and building things... I've assembled some Heathkit gear, built RF Amps of several flavors, built several repeaters, and designed/built so many items and widgets since 1974 I have lost track. I'll post items on here from time to time that I've built, or am in the process of building.

I also love restoring old radio gear. If you look at the Vintage listing on the Equipment Page under the WB4IUY header in the top menu, you'll see what I mean. I've probably got more old boat anchors to restore than I'll get around to in many years :-)

Homebrew Repeater Controller

Here's a homebrew Repeater Controller that I designed. It's purely analog, and provides 20 seconds of voice memory for ID's and messages; configurable courtesy tone generator; pre-tone, tone duration, timeout and hang timers; buffered COS and PTT connections as well as on-board audio gating. This was one of those "engineered-on-the-fly" projects, hi!

Homebrew Repeater Controller

Re-capping the Ameritron AL-82

I bought this Ameritron AL-82 amplifier from good friend and owner of Omega Electronics, Bill Edwards K4BWC (now SK) back around 1998. It finally began to make a loud "CRACK" every now and then from the HV supply, as one of the filter caps was beginning to go bad. I was talking with WIllie K3VW on the air about it, and he had replacement caps in stock for the repair. Willie works on lots of amps, and is very familiar with the AL-82. The caps he has were 220uf @ 500wvdc as opposed to the original 210uf @ 450wvdc, and only about 1/3 the physical size! More HV headroom, higher capacity, and smaller...you gotta love the progression of technology. Here are a few pics of the interior of the amp during the re-capping process.

You can see the original caps (blue) in one of the pics on the right. In another pic, you can barely see the pics through the perforated side of the cabinet...but you can see that they are MUCH shorter. There is also a pic of the RF deck in the amp, while I had the cover off. Click the pics for a larger image.

AL-82 Amplifier
AL-82 Amplifier

AL-82 Amplifier
AL-82 Amplifier

70cm Repeater Duplexers

This is a set of UHF Duplexers that I just finished modifying. They were orininally used in another service. I disassembled these and modified the internals to move them into the UHF 70cm amateur band. These are set up as "band pass" cavaties.

70cm Repeater Duplexers

220 Duplexers

This is a set of 220 Duplexers that I just finished modifying. They were orininally used in another service. I also disassembled these and modified the internals to move them into the UHF 1.25m amateur band. These are set up as "band pass" cavaties.

220 Duplexers

Repeater under construction...

This is a new repeater I'm working on for part of the 10m & 6m repeater system. It'll house new 10m and 6m transmitters, as well as the 70cm link radio and controller.

Repeater under construction

New HF Amp Project

Here are the tubes for my new HF Amplifier project. The big tubes are 4-1000's, and that's what I'm using in my new amp. There is a 3-500 in the picture to give a you a point of reference for the size of 4-1000's. They are beautiful tubes!

New HF Amp Project


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