Recent content by nomadradio

The very first caps to fail from age alone are frequently the ones rated for six or ten Volts. Around here we call that the "Ten Volt Blues". Manufacturing techniques have shrunk the size many radial caps found in a 45 or 60 year-old radio. We don't stock but one or two caps with a voltage...

Saw more than a few that had the low-profile heat dissipators on the plate caps, and a hole cut in the shield cover above each tube. The painted top cover would have a gap above the the tube cap sufficient to avoid arcs. Just can't use a heat dissipator that's taller than the tube's plate cap...

The difference is too small to worry about. People who obsess over a 15 or 20 percent power difference are impressed. But the S-meter at the other end of the conversation won't move more than the width of the pointer if that much. My practice has been to use the 1969 and not worry about a...

Some, but not all. 73

Must be getting old. Remembered this request as Uniden Washington. Yeah, same circuit board. Didn't find one picture of that procedure for that model. Did find the text file that got handed to a new tech. Here's the setup for that radio. Pretty sure the wire colors are the same. Find the wire...

Way cool! That radio had a devoted following 50 years ago. That was the era of "sideband clubs". Each one had a 'home' channel above channel 23. The AM operators considered them snobs. The console II is capable of excellent transmit audio when it's right. Pretty sure we ditched all the...

Darn well ought to. Reducing base bias to the mike amp is a lame way to control audio gain. 73

These folks have the genuine HG components. https://www.icamanufacturing.com/shop/p/hg-2sc1969 73

It's simpler. One diode comes loose, one resistor gets removed and one wire gets moved. My bedtime right now. I'll check back with the details later. 73

Sometimes it is. Especially when poopy audio is the issue. Just one problem. There's only one way to find out. Change them all and compare before audio to after audio. Or you could trace through the audio circuits, one capacitor at a time and identify the ESR for each. Replace the ones that...

So, how much did it drift before? Is this only a transmit-side problem, or does it drift on receive as well? All this mod does is to unook the fine control from the receive-only power source and connect it to the same one that powers the Coarse control. Any chance the clarifier only needs...

Pretty sure the chatroom thread he started concerns a Dentron GLA1000 that won't key. Unless this amplifier has been modified, you need either a foot switch plugged into the socket marked "relay" on the back panel, or a radio that has a linear-keying relay inside it. The GLA is a ham linear, and...

The "B" version of the tube is what the factory built it with also called 7034. The heater is rated at six point zero Volts, not 6.3. There are variations. The 4CX250R/7580 will deliver more power, but requires more negative-bias voltage to control it properly. The DX300's blower really isn't...

Way cool! I still have that LP. Somewhere... 73

I sell a pc board that simulates a zener with a string of forward-biased rectifier diodes. Has the advantage of being a bit less fragile than a zener in the face of a surge current. Its main appeal is to AM operators who ignore the factory's advice to select "CW/Tune" to operate AM. Cuts the...