Posts: 451
Threads: 85
Joined: Nov 2011
City: Cumming, GA
I have a Philco 42-327 Rider 14-31 http://www.nostalgiaair.org/PagesByModel...013515.pdf
Changed the caps and replaced a couple of missing tubes and powered up the radio and got static no smoke so far so good. It works on the sw as I have gotten some foreign broadcast at the high end of the scale. On BC I get static, set the signal gen to 455 and got tone at 480 with the gang fully closed should I be able to adjust this down using 24 A&B because it doesn't seem to move the signal just fade it in and out?
Eric
Posts: 7,286
Threads: 268
Joined: Dec 2009
City: Roslyn Pa
Did you try moving the generator down a bit then repeaking the trimmers on both IF's?
Terry
Posts: 451
Threads: 85
Joined: Nov 2011
City: Cumming, GA
Yes I did, the tone will fade as I turn the screw (24B) but when I turn the dial on the signal gen it doesn't follow. 24A doesn't seem do anything?
Posts: 7,286
Threads: 268
Joined: Dec 2009
City: Roslyn Pa
Do you have plate voltage on both plates of the mixer tube?? Where are you injecting the IF signal??
Terry
Posts: 4,703
Threads: 51
Joined: Sep 2008
City: Sandwick, BC, CA
These sets are a bit weird, they don't use a conventional convertor tube they use a dual triode mixer oscillator tube called an XXD/14AF7, they also have an extra IF amplifier stage. A stupid question but is the band switch set on dial tuning instead of pushbutton tuning? There are three IF transformers, the first has two trimmers but the second and third ones have one trimmer each marked 29A and 35A respectively, the 455 kc signal should go into the antenna section of the tuning capacitor.
Regards
Arran
(This post was last modified: 02-07-2013, 11:59 PM by Arran.)
Posts: 4,703
Threads: 51
Joined: Sep 2008
City: Sandwick, BC, CA
It is entirely possible that the oscillator for the broadcast band isn't functioning for some reason, a bad resistor, a bad mica cap, or even an open oscillator coil could cause this. I would start checking voltages on the XXD tube, particularly the oscillator section.
Regards
Arran
Posts: 271
Threads: 12
Joined: Nov 2005
City: Nashville, TN
Hi Eric,
Check the tube pins and make sure they are clean. Loktals are know to sometimes have a little corrosion in them, causing bad contact. Something simple to check.
Posts: 893
Threads: 9
Joined: Mar 2008
City: Vieques, PR USA
State, Province, Country: PR
Agree you need to realign the IF and check all the things mentioned. I once had a 42-327 that had the same symptoms as yours and mine turned out to be the local oscillator was not working on BCB but was fine on SW. Bad mica cap.
Posts: 451
Threads: 85
Joined: Nov 2011
City: Cumming, GA
Got a lot of things to check now. Thanks to all I will post when I know more
Posts: 451
Threads: 85
Joined: Nov 2011
City: Cumming, GA
Ok, when I started to see what the voltages were on the XXD and put the meter lead on pin 4 the radio started playing and you could tune in stations I followed it back to the OSC lead #6 is this an indication of an open winding?
Posts: 451
Threads: 85
Joined: Nov 2011
City: Cumming, GA
This morning started looking at the OSC and the mica caps especially at point 6 on the OSC first checked #9 and it came in at 260pf. Then # 5on the print calls for 5pf but the dots on the cap say it should be 100 pf but reads 19pf so I put in a 10 and nothing then put in a 100 and the radio plays fine. Thanks for the help now to clean the chassis and the cabinet. Love this site!
Eric
Posts: 2,128
Threads: 18
Joined: Oct 2008
City: Merrick, Long Island, NY
Me too, was on my Philco. SSDD. Glad you gort it working.
Posts: 893
Threads: 9
Joined: Mar 2008
City: Vieques, PR USA
State, Province, Country: PR
Congrats, Eric. I can't recall which was my bad cap...I'm thinking it was #9. What I remember most is that it was the most buried one in that part of the circuit!
Users browsing this thread: 1 Guest(s)
|
Recent Posts
|
HiFi (Chifi) tube amp build - but my own design.
|
Tim,
nice write up and thanks for sharing !!
Sincerely Richardradiorich — 02:47 AM |
HiFi (Chifi) tube amp build - but my own design.
|
Well, this was a real "Hum-Dinger" :lol: ! This will be kinda long, but hopefully it will help others having t...TV MAN — 01:55 AM |
Shadow Meter Bulb
|
Phorum members, I am trying to find the bulb # for PHILCO Shadow Meter part number 45-2180 that is from a 37-640 chassis...georgetownjohn — 06:53 PM |
Philco 41-608 changer coupler
|
3D-printing...short of machining, of course.
Or molding.morzh — 05:20 PM |
Philco 41-608 changer coupler
|
Thanks, Morzh.
That solves the issue of the rubber pieces. Now, I need to find a way to replicate the pot metal piec...alangard — 05:07 PM |
12' Philco
|
If it is 12', either Kareem or Andre would have to jump pretty high to look at the front panel.
Kareem would have an e...morzh — 01:48 PM |
12' Philco
|
And here's a story about the tires on the truck. Same "no-stoop" guy must have installed these! Take care a...GarySP — 01:17 PM |
Hickok AC51 tube tester
|
I think they have only shown the secondaries of the transformer.
Two of them feed the rectifiers' filaments.morzh — 12:58 PM |
IF can wire size and Rubber mounts?
|
Arran
If the wire inside cans is the gauges you mentioned, the sole reason for that would be mechanical, to stiffen t...morzh — 12:56 PM |
12' Philco
|
Rod,
Yes, I know, but the Giant Philco is not around anymore either, so I go by whoever was alive fairly recently.
H...morzh — 12:54 PM |
Who's Online
|
There are currently no members online. |
|
|