Welcome Guest! Be sure you know and follow the Phorum Rules before posting. Thank you and Enjoy! (January 12, 2025) x

Thread Closed

37-690 Alignment
#1

The IF's aligned easily, except for this step where it appears you are expected to get two peaks on either side of the IF freq. That just doesn't  happen, and I'm not sure how it ever would unless I'm misunderstanding the instructions. My interpretation: "adjust signal generator back and forth between 460 and 480, you should get equal 2 signal peaks, one at 465 and one at 475.  If you don't, adjust the primary padder of 94 left and right of peak until you do".  I can wrench on that padder all day long and never get anything other than a single peak at the 470 IF.  Any thoughts as to what I'm doing wrong?
           

RJ Dial
"Radiodial"
Mendocino, CA
#2

The coils have probably degraded, holding corrosion and moisture and your won't get that double high fidelity peak. Make sure your sig gen and hookups are in good shape and not causing it. Old test leads that have bad connections in the alligator clips can mess it up, leading you down the wrong path. Clean the fidelity contriol also.
#3

I got the double peak alignment part to work by:
1- Discovered that "Fidelity control in expanded position" means turn the Selectivity/Treble control Counter-Clockwise.
2- Wearing hearing protection and increasing the volume to full and setting the signal generator output to high.
The other key was all it takes is minuscule adjustments on the 94P coil, and sure enough, you are able to get dual peaks 5khz eeither side of the 470 khz IF.

RJ Dial
"Radiodial"
Mendocino, CA




Users browsing this thread:
[-]
Recent Posts
54C Complete Teardown/Rebuild
Hello Roy, here is this one sincerely Richardradiorich — 12:45 AM
54C Complete Teardown/Rebuild
Richard, Had grabbed it already but thank you just the same.  I find myself wanting to find some way to block out the...glyphmon — 12:03 AM
54C Complete Teardown/Rebuild
Hello roy, here is a link to the schematic . Sincerely Richardradiorich — 11:54 PM
54C Complete Teardown/Rebuild
Richard, The Silvertone 2014 also is a transformerless set, so I am incorporating a 1:1 600 ohm audio isolation transfo...glyphmon — 11:37 PM
Preliminary work on wife's Silvertone 2014
Did an alignment today which was interesting.  IF alignment went great, almost all was already spot-on.  Adjusting on th...glyphmon — 11:35 PM
54C Complete Teardown/Rebuild
The main problem with adding a Bluetooth input is that this set lacks a traditional power transformer to isolate it from...radiorich — 11:19 PM
54C Cabinet Refinish
I started stripping this cabinet before it got super chilly out because I knew I wasn't going to be able to work on ...glyphmon — 11:18 PM
54C Complete Teardown/Rebuild
While I'm waiting to wrap up the final steps on my wife's Silvertone 2014, I started disassembly on the next project.  O...glyphmon — 11:07 PM
Preliminary work on wife's Silvertone 2014
Hello roy, that great news glad it worked out for you !! Sincerely Richardradiorich — 10:50 PM
Preliminary work on wife's Silvertone 2014
Safety caps arrived today.  Soldered one in and had a successful first power-up.  No magic smoke escaped and it tunes in...glyphmon — 09:53 PM

[-]
Who's Online
There are currently no members online.

>