Model 57 compensator values?
Posts: 15
Threads: 3
Joined: Apr 2015
City: Seattle, WA
Can anyone tell me the values of the four compensating capacitors (trimmers) on the model 57?
I took mine apart and carefully marked them but according to the schematic they were wired wrong. I want to put the radio together right so I am not sure where they go. Caps are 12, 15, 18, 19. Thanks.
Bob Atchison
Happiness is a warm glowing radio!
Posts: 5,088
Threads: 270
Joined: Nov 2012
City: Wilsonville
State, Province, Country: OR
Hi Bob, Welcome to the Phorum. Here's a schematic link for folks who might be able to help with answers.
Posts: 7,286
Threads: 268
Joined: Dec 2009
City: Roslyn Pa
Unfortunately the diagram and parts list don't divulge the actual values of the trimmers. You maybe able to find out via the part #s. Or if you have a capacitance meter you could measure them and take an educated guess as to where they go ( the lower the fq the higher the capacitance)
Definitely will need to use a generator to align the IF trimmers, they will make a big difference if they are off.
Terry
(This post was last modified: 04-08-2015, 07:26 AM by Radioroslyn.)
Posts: 15,825
Threads: 554
Joined: Oct 2011
City: Jackson, NJ
Why do you need values?
I think those mounted on tuning cap, osc and ant, are the same, and the two in the back are likely shown correct. One of them, the 19, is the feedback regenerative circuit cap.
My guess as to the value of the ones on the tuning cap is maybe 20-30pF. But as long as you have them, the value is of no concern.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
Posts: 7,286
Threads: 268
Joined: Dec 2009
City: Roslyn Pa
Well there two on the tuning condenser,one in the lo circuit, two across IF trans, the regen control. So there is six all together. Best I remember some of them are isolated from the chassis. It may turnout that they are close enough in value that it doesn't matter which one goes where.
Terry
Posts: 15,825
Threads: 554
Joined: Oct 2011
City: Jackson, NJ
Obviously regen cap should go where it was before as otherwise you won't have the regen control easily accessible as intended, from the back of the chassis.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
Posts: 7,286
Threads: 268
Joined: Dec 2009
City: Roslyn Pa
The regen control has the fiber nut on it the other are brass.
Terry
Posts: 15
Threads: 3
Joined: Apr 2015
City: Seattle, WA
OK That's one. There are still three that I can't figure out, and they are not the same value because there are a different number of plates. I do have a cap meter, but I need to know which one goes where. thanks all!
Happiness is a warm glowing radio!
Posts: 13,776
Threads: 580
Joined: Sep 2005
City: Ferdinand
State, Province, Country: Indiana
Take a look at the back side of each trimmer. The Bakelite insulator should have one letter stamped multiple times all over it. Match that letter to the parts list.
One should be stamped with the letter A, one with D, and one with S. The regeneration control, part (19), probably will not have a letter on it.
A - part (12), IF primary, part no. 04000-A
D - part (18 ), IF secondary, part no. 04000-D
S - part (15), low frequency padder, part no. 04000-S
--
Ron Ramirez
Ferdinand IN
Posts: 15
Threads: 3
Joined: Apr 2015
City: Seattle, WA
You'da man, Ron. Thanks!
Happiness is a warm glowing radio!
Posts: 15
Threads: 3
Joined: Apr 2015
City: Seattle, WA
I checked all the trimmers, they are correct. I still have this horrible oscillation at full volume, low frequency, not a hum, more like a screech. It breaks into it just about the time you get a station tuned in either on the main tuner or on one of the trimmers. Any ideas???
Happiness is a warm glowing radio!
Posts: 5,088
Threads: 270
Joined: Nov 2012
City: Wilsonville
State, Province, Country: OR
Too high (clockwise rotation) on the regen trimmer will cause screaching, does backing it off (counter clockwise rotation) help?
Posts: 13,776
Threads: 580
Joined: Sep 2005
City: Ferdinand
State, Province, Country: Indiana
This radio should have a tube shield over one or both of the 77 tubes - I do not remember as I do not own one, but it is one or both of the 77 tubes. In any event...is (are) the shield(s) in place?
--
Ron Ramirez
Ferdinand IN
Posts: 15
Threads: 3
Joined: Apr 2015
City: Seattle, WA
Nothing I do will stop it till I power it off then back on. I can back out the regen trimmer but then I lose everything
Happiness is a warm glowing radio!
Posts: 15
Threads: 3
Joined: Apr 2015
City: Seattle, WA
That makes sense but only one has a shield and only it has the ring at the bottom for it. my radio looks like the one here:
http://www.radiomuseum.org/r/philco_57.html
Happiness is a warm glowing radio!
Users browsing this thread: 1 Guest(s)
|
Recent Posts
|
Philco 38-7 Oscillation
|
I have let this one sit because of other duties. Now I am back, and I have a couple of questions. I hooked up a Hammond ...tludka — 11:16 PM |
Philco 38-7 Speaker
|
I know that when I first started working on this radio, I did not even have a speaker. Once I finally found one it was n...tludka — 11:00 PM |
Philco 60 Squealing
|
I seem to remember eliminating a squeal by changing the IF frequency by a few KHz. Not that you should put too much tru...fenbach — 08:48 PM |
Philco 42-390, code 121 speaker
|
These speakers pop up on eBay regularly, even if at bloated prices.
Honestly, have not seen many parts on swapmeets.morzh — 08:38 PM |
Philco 38-7 Speaker
|
The put-put is not like the speaker problem.morzh — 08:29 PM |
Mission Bell Model 19A Car Radio
|
Hello everyone,
As mentioned in my last post I was going to see if the vibrator / rectifier section could be persuaded...Antipodal — 08:21 PM |
Philco 60 Squealing
|
Wondering if I did it backwards.
If a coil was wound backwards, the oscillator would not work at all.
Old school...Chas — 07:23 PM |
Philco 38-7 Speaker
|
4-ohm speaker. Black, Green leads.tludka — 07:00 PM |
Philco 42-390, code 121 speaker
|
#87 on the schematic.
This radio had a 8" Zenith speaker attached to it when I got it. I do don't know the hist...Stevelog — 06:39 PM |
Philco 60 Squealing
|
I'm pretty sure I now have the litz wire soldered. This did not make any difference. Back in April I rewound the seconda...dconant — 06:25 PM |
Who's Online
|
There are currently 3411 online users. [Complete List] » 1 Member(s) | 3410 Guest(s)
|
|
|
|