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Old 11-08-2016, 04:31 PM
Kevin Kuehn's Avatar
Kevin Kuehn Kevin Kuehn is offline
Workin' Late Again
 
Join Date: Jan 2011
Location: WI
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Quote:
Originally Posted by Crist Rigott View Post
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.

Quote:
Originally Posted by Crist Rigott View Post
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.

Last edited by Kevin Kuehn; 11-08-2016 at 04:57 PM.
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