Posts: 825
Threads: 113
Joined: Aug 2012
City: The Villages
State, Province, Country: Florida
I'm working on a 48-482 and I've run into a problem. The only schematic I have been able to find shows a 6SQ7 as the first audio even though all sets have a 7B6 in its place. I have a tube diagram for the 7B6 but it would sure be a help if I had a schematic that shows the 7B6.
Does anyone know where I can get one?
Thanks,
Eric
BTW. The problem is: squeal like feedback when turning up the treble control and with a long wire antenna I can only get one local station all over the dial. Has been re-caped. Tubes and resistors replaced as nec.
Eric
The Villages, FL
Member: Philco Phorum, ARF, ARCI & Radiomuseum.org
(This post was last modified: 12-10-2012, 07:05 PM by Eric Adams.)
Posts: 2,128
Threads: 18
Joined: Oct 2008
City: Merrick, Long Island, NY
Schematic here
http://www.nostalgiaair.org/PagesByModel...013637.pdf
Tube data here for 6SQ7, 7B6 and anything else you wish.
http://www.nj7p.org/Common/Tube/SQL/Tube...?Type=6sq7
Both tubes do the same thing, and often whatever was available was used in production and changes were not always documented.
Posts: 825
Threads: 113
Joined: Aug 2012
City: The Villages
State, Province, Country: Florida
Thanks Codefox1, The schematic is the same as I have but the tube digrams are much clearer. Everything checks out at the 7B6. I guess it's back to the trouble shooting guide.
Eric
The Villages, FL
Member: Philco Phorum, ARF, ARCI & Radiomuseum.org
Posts: 151
Threads: 4
Joined: Oct 2005
City: Sullivan, MO
There is a factory service manual for this model on this page although it also shows the 6SQ7. It is in DJVU format so you will need a reader.
http://www.audiophool.com/Philco.html
Sean
WØKPX
(This post was last modified: 12-11-2012, 10:35 AM by Sean.)
Posts: 825
Threads: 113
Joined: Aug 2012
City: The Villages
State, Province, Country: Florida
Thanks Sean, that's the info I have now. I'm looking for something that shows the 7B6.
Eric
Eric
The Villages, FL
Member: Philco Phorum, ARF, ARCI & Radiomuseum.org
Posts: 289
Threads: 40
Joined: Oct 2011
City: Las Vegas, NV
Eric, AFAIK all the published prints show the 6SQ7, but the only difference is the pin numbers. That said, this weekend when I have some time, I'll pull a working chassis and take some voltage and resistance measurements. Maybe we can pin down the problem that way.
John
Las Vegas, NV USA
Posts: 825
Threads: 113
Joined: Aug 2012
City: The Villages
State, Province, Country: Florida
Thanks John, hope to hear from you soon.
Eric
Eric
The Villages, FL
Member: Philco Phorum, ARF, ARCI & Radiomuseum.org
Posts: 21
Threads: 3
Joined: Sep 2023
City: Eagle River
State, Province, Country: Wisconsin
6SQ7
https://www.nj7p.info/Tubes/SQL/Tube_que...?Type=6sq7
If this link above doesn't work, go directly to NJ7P's website and enter the tube your looking for
Tube Database Website:
https://www.nj7p.info/Tubes/SQL/Tube.php
Posts: 2,263
Threads: 164
Joined: Jan 2013
City: Westland, MI
The schematic in the Philco Radio Library accessed at the bottom of the Home page shows the 7B6.
https://philcoradio.com/library/index.ph...year-book/
Take care and BE HEALTHY! Gary
Thought I'd point it out, even though the thread is 11 years old!
"Don't pity the dead, pity the living, above all, those living without love."
Professor Albus Dumbledore
Gary - Westland Michigan
Posts: 13,776
Threads: 580
Joined: Sep 2005
City: Ferdinand
State, Province, Country: Indiana
EagleRiverMike,
Welcome.
I use Bill's (NJ7P) SQL tube database query all the time - it's much easier than getting out one of my tube manuals.
But I should mention this thread is 11 years old, and the OP (original poster) hasn't visited here in nearly two years (I hope he's ok).
--
Ron Ramirez
Ferdinand IN
Posts: 2,263
Threads: 164
Joined: Jan 2013
City: Westland, MI
Guess Ron and I commented simultaineously! Take care and BE HEALTHY! Gary
"Don't pity the dead, pity the living, above all, those living without love."
Professor Albus Dumbledore
Gary - Westland Michigan
Users browsing this thread: 1 Guest(s)
|
|
Recent Posts
|
|
Plug Voltages Needed For A 1943 CRV-20130 Power Supply
|
| That looks a lot like an aircraft connector of some kind, even if it's a U.S.N power supply. I have a book somewhere abo...Arran — 02:56 AM |
|
Plug Voltages Needed For A 1943 CRV-20130 Power Supply
|
| hello david,
I have a similar generator in my collection that features a cast iron, single-cylinder Briggs & Stratt...radiorich — 01:00 AM |
|
under chassis parts locator diagram for 1938 Zenith 9s262
|
| Has anyone gone to the trouble of creating an under chassis parts locator image? Yes, I can identify components by foll...bobloney — 08:57 PM |
|
Plug Voltages Needed For A 1943 CRV-20130 Power Supply
|
| Try looking at this site the book mark is for a old generator that I was given. David https://radionerds.com/index.ph...David — 08:36 PM |
|
Plug Voltages Needed For A 1943 CRV-20130 Power Supply
|
| Hello Everyone,
I am looking for voltage identification for all the pin positions on the socket of a CRV-20130 power su...Tonym4704 — 08:16 PM |
|
Philco P45-6365 Universal Transformer Instruction Manual
|
| Can anyone guide me to where this may be found?GRG — 03:00 PM |
|
54C Complete Teardown/Rebuild
|
| I don't think that I have encountered a 12Z3 before, curious how it uses one of those but includes a #43, which is a 25 ...Arran — 02:17 PM |
|
HiFi (Chifi) tube amp build - but my own design.
|
| It's the other forum. I'm also in DIY, but mostly read there. Honestly, I kinda jumped into this without much thought to...TV MAN — 10:43 AM |
|
Philco 71 Code 125
|
| Hello,
I am in need of a schematic for this radio. Mine has the three separate circular tube shields and a shadow me...dconant — 08:06 AM |
|
Stromberg Carlson 1500 Squeal
|
| And life just keeps getting more complicated.dconant — 07:57 AM |
|
Who's Online
|
| There are currently no members online. |
|
 
|
![[-]](https://philcoradio.com/phorum/images/bootbb/collapse.png "[-]")
