Admiral 14R12 Restoration

[Kevin Kuehn]

Originally Posted by Crist Rigott

Just an update on the alignment.
I decided to check the tuner and work back through the TV. When checking the tuner on channel 3 it wouldn't align. The frequencies were too far off. I then decided to check channel 4 and sure enough the freq. were much closer, so I decided to use channel 4 instead of channel 3. Channel 4 aligned perfectly with the waveform and frequencies where they should be.

So if I'm following this you injected the correct rf carrier signal into the antenna terminals for the selected channel? If so possibly the rf and oscillator coils for Ch 3 are interchanged with some other channel on the tuner drum.

Originally Posted by Crist Rigott

I used a meter to align the first step in the 4.5mc audio section. But the 2nd step didn't work out so well. I never could get the meter to zero out. I hooked up the sweep generator and o'scope and peaked per step 1, but never could get the cross over pattern in step 2. I ended up just tweaking by ear.

Were you using a vacuum tube voltmeter? Otherwise a standard 20,000 ohms per volt meter will load that circuit and you'll never get it to zero. You could also use a scope set to DC coupling.

[Crist Rigott]

Yes, I was using my VTVM. Next time I'll double check on the DC coupling. I just checked the scope settings and they were on AC coupling. that could have been the problem?

[Crist Rigott]

I finished making a new back. The original had several flaws besides the upper mounting holes being enlarged as to be ineffective.

The right side back brace was located too high and interfered with the upper mounting boss. This skewed the whole back and it warped badly from the chassis screws forcing the back back into position. With the brace too high this brought the whole edge down low and the bottom of the back overlapped the bottom of the cabinet. Also somewhere along the way, the interlock on the chassis was changed out probably because of the extreme pressure of the mal-aligned back.

All of these problems were corrected with the new back. I also added 2 1/16 ply shims to the back which runs up against the chassis so when the mounting screws are tightened, they won't warp the back. This is due to the metal interlock bracket. I used some Dewalt brad-point drill bits to drill the holes.

I changed the power cord and made up some new labels too.

[Crist Rigott]

I polished up the knobs and finished the project today. In reality, I still need the metal insert that goes into the channel selector knob. I must have lost it when at my daughters house.

I'd like to thank everyone who helped me get this one done. I learned a lot and you guys have spent some time with me helping me through the process. Thank you.

Here are the final pics.

[Kevin Kuehn]

Originally Posted by Crist Rigott

Yes, I was using my VTVM. Next time I'll double check on the DC coupling. I just checked the scope settings and they were on AC coupling. that could have been the problem?

Yes, at that point you're measuring a DC voltage that varies plus and minus.

Holy cow, that back looks like the real deal, excellent work!!

[Crist Rigott]

Originally Posted by Kevin Kuehn

Yes, at that point you're measuring a DC voltage that varies plus and minus.

Holy cow, that back looks like the real deal, excellent work!!

Thank you Kevin.