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Could be a waste but maybe all it needs is a 1306 and 1307 set from an old 23 ssb. Vcc is the same, ground is ground, a littlr biasing and a coupe of protection diodes across the finals just might work. I got spare parts and im retired so it'll be a winter project.

Seems so

Ive heard that. I dont have the second gen to compare it with. I know that they removed that little board in the back of it. Thats all I know about it. Without a schematic its been a real treat NOT finding my way through it. Lucky its the finals. Simple layout. Id hate to have to figure out the...

I will be experimenting with replacing the transmitter section. But for now its on the back burner. If yours survived, thats good. Mine however will be modified.

Why you ask? Just read up about the history of the transmitter section of this radio and you will understand why. I could go on and on about the problems but I'd be writing boring stories for days.

Im going to figure out how I can make a new transmitter section with more common parts. I think the old standard 2078 transistor would work great on AM but on SSB wouldn't push more than 5 watts peak but using a small linear would fix that. 2078 transistors are cheap. Using a pair of 1306 and...

Thanks for that post about the Pres Mckinley box I appreciuate having the SM but its definityely not the same board as my 2 90s. A quick look at the board layout and my radios is so different its not funny. Example, on mine the ground is on the center pin of the final and the mckinley its on...

youre not kidding!

It might be but definitely not in my 2 980 ssb jobs. mine are RD16HHF1 and if there is a driver to the mosfet its not obvious.

Great history there! Love the johnson line. Very good output and rock solid modulation.

I wish there was a schematic somewhere. I have 2 first gen boxes. 1 had blown rd16hhf1 mosfet and the 1725 pnp transistor. Surface mount components and double sided board with eyelets. No hell to work on. Checked and compared the good radio to the bad. Resistance and then voltage checks. Anyhow...

Ok brother. Keep me posted. Need both for channel 6. 73s

Looking for a set of channel 6 crystals for my whiteface.

Well, you were right. I found a donor radio with an authentic set of finals and swapped them over. The known good radio dropped in power to less than half and the 448 got the known good original NEC set. Problem solved. Thanks guys for your support. I learned a good lesson. DO NOT TRUST CHEAP...

There are 3. Part of the 34mhz AM and SSB oscillator cct. T6, T7,T8. T7 has no inner cap. The other 2 do. Sams doesnt show the values on the schematic and the parts list doesnt show any tuning coils. T7 Feeds T8. There are 2 tuning caps in that circuitry. These culprits are all located under...

Could be fake. There are 3 different combinations of finals for this radio. 1306, 1307 is 1 combo, another is 2020 and 2098. The 3rd I can't recall.off hand. I have about 100 radios here in the shop. I could pull a set of known working ones from another rig but at this point I think there are...

A Audio its killer. Ears killer. O just gotta get it transmitting properly. Its not the driver or final. It has to be coming from the TX feed somewhere upstream

Ivecseen a similar issue with old zenith radios that have a silver sided cap in the can. They oxidize and short out causing smoke to escape. This particular can is located up front inside one of those shield covers. Its on the same side as the output. It may very welk be associated with both rx...

I aligned it with respect to the sams. Twice. I will do it again. I do have one slug flush withthe can. I think its a frequency alignment for the receive. All of that side seems to be pretty good now. Center of clarifier is pretty good too. It has very good ears. The voltages on the 2066 and the...