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I'll check that but did you mean TR1? TR11 emitter is tied to ground in the Sams schematic and TR1 looks to be the oscillator. 73,

Howdy, y'all! Just picked up the above radio with a few problems. It was totally dead when received and I found two exploded diodes on the PS board along with a 25A line fuse!! :oops: After replacing the diodes everything seemed fine until I keyed the mic and ka-boom, diodes fragged again...

Thank you, Dan!

Dan - You are always appreciated!! As usual, I am also in need, as usual. I picked up a Pearce Simpson Bengal SSB that has a couple of "issues" so I am in need of a Sams for it.\ Again, thanks for everything you do for the radio hobby.

Yeah, I gave all of the trimmers a good hosing and nothing changed but I noticed a few felt really "loose" when turning so maybe some are not making good contact at the wiper.

I decided it would be a good idea to pull down my collection of radios, dust them off, test, and pack in big zip-lock bags with a couple of desiccant packets. Maybe I should have left well enough alone as about half of them have developed "issues" while being on the shelf for a few years...

I took a look at the transmitting "purity" with my TinySA and with the VFO injecting a square wave I couldn't see any spurious signals so I guess I'm good to go!

Interesting little board. I'm running the 9850 output to the radio through a .oo1 uf cap so I doubt it would be loading it down. It seems to work fine with the gnarly square wave but I've read that using a square wave might result in some spurious emissions. I need to drag out my Tiny SA and...

After my successes with adding a VFO to my pair of Midland 13-898Bs I pulled my old Pace Sidetalk off the shelf and started messing with it. Here are some observations: 1. The VFO can be added using the same method as for the Midland. 2. The "standard" sine wave output (1V PP)from the DDS...

Dan - I'll take it! I'll PM you my details...

I basically used the code and hookup diagram from here: https://www.ad7c.com/projects/ad9850-dds-vfo/ About the only thing I changed was using an I2C interface display. Parts needed are the Arduino, AD9850 board, rotary encoder, a 1K resistor, wire, and some perfboard. Here's the VFO on a...

Finally finished up this project. I added a SPDT switch to the back of the chassis to switch channel 23 position between VFO and the original crystal. Everything works great and if I can ever find a clock motor this will be a perfect base station. Here's some final pics: I removed the .001...

My brain started getting tired so I pulled the RT40 back out. I probed around all over the place and none of the voltages made any sense. After beating my head on the bench for more than an hour I realized that I can't ground the meter to the chassis, like all other radios I've worked on, but...

Thanks, Nomad. I can't remember but will check next time I get the cover off. Right now I'm in the middle of writing new Arduino code for my VFO. I may take a break from it later today and check.

Hopefully somebody can help me with this or tell me it just needs to go into the scrap bin! I picked this up a couple of years ago and stuffed it into the "someday" pile. The someday pile is nearing the end so I pulled it out the other day and started messing with it. Lights work, slight...

The parts showed up this evening and I took my goodies out to the shop. I replaced the 16V zener, Q1 with a 2N3904, and the pass transistor (Q5) with a TIP41. Firing it up everything was perfect and I was able to adjust the voltage to spec so I'm a happy camper. Q5 was completely shorted so...

OK, ordered a bunch of parts from Amazon. 1. I removed Q1 and found it "open" all the way around so subs for 2sC900 on order. 2. With the transistor out of the circuit I still get +22 V out so I found that the "pass transistor" Q5 2SD333 can have a TIP41 subbed so that's on order as...

After messing around with this I have made some determinations. A previous "goober" replaced X102 and X103 to get different channels. X103 was replaced with a 7.9100 MHz crystal which puts channels 9-12 at channels 36, 37, 38, and 40. X102 was replaced with a 7.9433 MHz crystal which will put...

OK, putting my signal generator (1.5V signal) across the 11.295 MHz crystal the receiver came alive! I tested a few channels by testing it with a walkie and the reception was OK. I now have what I hope is one last problem to solve. In SSB I get full output on dead-key so the balanced...

After removing the sig gen from crystal I tweaked the trimmer for that crystal and it started working! I've had h\Heathkit HET Osc do that, too. I think I jynxed myself wondering about what else the "tech" that twisted the wires together and taped on the replacement lamps might have jacked...