Zenith table radio - phono works, no AM/FM

FM works!

:banana:

With some detailed directions from TV Engineer, I recapped all the IF transformers over a series of afternoons and evenings. That was some incredibly delicate work.

FM works now, although with hiss and sometimes distortion, indicating it needs to be aligned. Stations come in stronger on AFC than without.

I get a little mains hum on AM, and if I rotate the dial quick, I can get "thumps" that are probably stations, so AM probably works, but the alignment is WAY off. Although when I first brought the set up on the variac, there was a little bit of static followed by a small POP, so maybe something toasted. I pray it's not inside one of the cans (coil grounded to chassis). I can get some small pops when I touch a screwdriver to the AM antenna connection, so that's a hopeful...
 
FM performance has gotten better with time, and it's now playing Gunsmoke loud 'n clear (within the fidelity and distortion of the old recordings).
 
Alignment tools, PE signal generator & 40mhz USB oscilloscope on order. Everyone specifies a VTVM, but I figured as long as I wanted the IF frequency dead-on, for the cost of a combo signal generator/frequency counter (or separates) & 11meg VTVM, I could have a cheapie analog frequency generator (hopefully nice 'n stable) and a "do it all" o-scope with x10 probe. All calibrated & under warranty, to boot!
 
Aligning the tuner!

OK, here I go, trying to align the thing. I've got an RF signal generator, oscilloscope, and the special plastic tools to do it with. Also, I have the Sams Photofact instructions, and a glass of chocolate milk.

Starting with AM, per the instructions. Wish me luck!
 
All done- happy ending!

So, I halted work following an alignment-related computer blowup (smoke & sparks). Then I continued to halt work while I stripped the exterior of my house down to studs & re sheathed, insulated, windowed & Hardie'd. Then I halted again while I re-bathroomed the master suite. Now I'm halted because my first daughter was born last week.

But I did turn the set back over to the friend who gave it to me, after he recapped & refinished a 1941 10-tube Zenith curbside scroe, which is fabulous now. With a USB o-scope, Parts Express signal generator, and just the simple instructions on the Sams page, he aligned the set in about 30 minutes, and it's playing really strong. AFC is still wonky, but that's another bug to trace. Maybe a weak tube.

I think he is an ace radio tech. Doesn't know much tube theory, but he's awesome at recapping, rewiring, and cabinet restoration. I will be turning several chassis over to him without hesitation, and he is hungry for more vacuum tube adventure. Some of my sets will involve circuit mods & some tube theory (Maggie balance pot removal, preamp redesign on an organ amp), which I think is the next step in his learning. Finally, we'll do something with the 900V B+ Altec 1570B I've got in my basement. Maybe we'll pair that mutha with a refinished 4x12 cabinet and an Alembic preamp clone. Maybe we'll build some flea-powered 12au7 stereo amps. So many ways to go.

I will try to get pictures of the finished '61 Zenith if I can.
 
DAMN! You HAVE been at the "Honey-DO's! How the hell did you find time to have a kid, too??? Congrat's! I just became a Grandpa last Saturday. Little Girl.

Gotta come down and check out the house (having seen it as a before "This old house"). The Nordmende is still working, but the DUAL in it bit the big one. Gotta find a replacement table one of these days.

Glad you finally got this one done. It's been a long road.

Larry
 
Thanks, Larry! And congratulations to you too!

For the kid, I just showed up. Dad is just an accessory at the hospital, but the real work for me started when we got home. All is well.

What took me over a year to slowly do in spurts would take my tenacious friend an afternoon including alignment. I have humbly turned my skills to being an ace diaper tech. Where the Nordmende sat is now hardwood floors and a nursing station. Glad to hear the set still plays strong.
 
All cleaned up

Cabinet expertly cleaned, knobs repainted, this thing looks fabulous in person. I gave my friend an orphan 70's hifi tweeter out of my stock to replace the dead original unit, and it sounds good. Doesn't blend seamlessly, there's a hole around what I think is the xover freq, but it's a good improvement. Will try reversing the polarity.

The best part of all, is this set is ready just in time to be given back to my friend's dad (it was his set all along) for his birthday later this week.

FM AFC works strong, FM works now (took a while to "come in"). There's just one AM station that comes in, but nobody is going to listen to AM on this set, so it's OK.

That's it for this set!
 

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