Recent content by nomadradio

And if you can afford it the Icom IC-718 is a good performer for the price. 73

If it just needs an amplitude boost, I sell a board on fleabay that does this. https://www.ebay.com/itm/117262133570?mkcid=1&mkrid=711-53200-19255-0&siteid=0&campid=5336136228&customid=&toolid=10001&mkevt=1 Has a trimpot to set the desired drive level. It ain't cheap, but the schemo is posted...

The road to Hell is paved with good intentions. The DX300 I'm rehabbing this week was gonna be the photo model for my HV transformer substitute package instructions. But I got greedy and it's being rebuilt with the original HV transformer. I'll get paid sooner this way. But there's another...

Hmm. Displaying 10.695 does make it sound as if the PLL's 16 MHz output isn't getting into the counter module. Not since about 1973 have I tried to troubleshoot a counter problem without a 'scope. And that counter used vacuum tubes. Did get it working, though. I did have a schemo for that...

Why is it so hard to find a good 1978 Firebird I can just use as a daily driver? Aside from how many of them were totalled by adolescent or drunk (or drunk adolescent) drivers in the last 48 years, you'll need to basically rebuild one that isn't a genuine "barn find" with low mileage. 48 years...

Good point. You wouldn't choose a 50-year old model as your first car. Especially if it would need an overhaul before you could drive it to work every day. 73

The Amphenol "86" series of plugs included the 8-pin that was identical to the base of an octal tube. Basic number was "86-CP8". The suffix numeral showed the pin count. The radio above has a 86-CP9 sticking out the rear. The mating socket was the series 78 connectors. Original catalog number...

Excellent job! Just watch for glitchy connections from top side traces to bottom side foil traces. They used small pins commonly called "griplets" soldered to foil on both sides. They have a tendency to develop fatigue cracks and cause intermittent faults. 73

Just over 30 years ago, a customer wanted a roger beep that nobody else had. Started with a "Roger K" board and hacked it to become the infamous "Bump-Bump". The CAD system we used back then under DOS was called Supercad, sold by a company called Mental Automation. They have been gone for a...

Way cool! 73

Not to put too fine a point on it, but did you verfy the PLL chip has power? Troubleshooting a dead radio should begin with an inventory of all the power supply branches and regulated voltages. A radio old enough to use zener diodes to regulate critical circuits especially. Dead zeners were a...

That connector is for the power supply. Doesn't have one built in. That was a base or mobile radio. A separate power supply was used for DC-powered mobile and another for AC use indoors.

Rock on! Gotta love it when a plan comes together. 73

Hmm. The schematic above doesn't seem to indicate R1 and R2. Which ones are they? 73

https://www.worldwidedx.com/threads/pride-dx300-basket-case-no-maybe-more-like-body-bag-case.264657/ Found it. Shows the two transformers we use. Also shows that each power supply board has to be modded to accomodate the substitute transformer. Mostly a matter of larger filter caps. 73