Posts: 322
Threads: 62
Joined: Mar 2007
City: Toledo
State, Province, Country: OH
Working on this 46-200 and its a version where the 35Y4 has been replaced with a 35Z5, code 122. There is a cadohm resistor in this that Riders does not show. Connects between pin 2 of the 50L6 (filament) and pin 7 of the 35Z5.
Pin 7 of the 35Z5 corralates to pin 8 of the 35Y4 which would be part of the filament string. I'm measuring 83 ohms across this. Is this a good reading for this or has it drifted way out of tolerance?
Posts: 1,703
Threads: 55
Joined: Sep 2005
City: Evanston, IL
Riders most often shows the original Code 121 version schematics and sometimes in later volumes any production change notes - many times not.
Let me check the Code 122 version service bulletin when I get home and I'll get back to you here...
Posts: 322
Threads: 62
Joined: Mar 2007
City: Toledo
State, Province, Country: OH
Posts: 1,703
Threads: 55
Joined: Sep 2005
City: Evanston, IL
That candohm, R100 is the same in the Code 121 schematic and in the Code 122 version schematic - didn't change. 80 ohms.
Posts: 322
Threads: 62
Joined: Mar 2007
City: Toledo
State, Province, Country: OH
Thanks Chuck, but now I'm confused. Riders says the 46-200 is in volume 16 page 9 for Philco. That schematic has no R100 or a resistor with a value of 80 ohms. Also it shows a tube lineup of 7A8, 14A7, 14B6, 50L6, and 35Y4.
The label on my cabinet clearly states a model 46-200 codew 122 with a tube lineup of 7A8, 7B7, 7C6, 50L6, and 35Z5. The chassis is also stamped as a 46-200 code 122. So what gives?
Posts: 1,703
Threads: 55
Joined: Sep 2005
City: Evanston, IL
You have a Code 122 version. Have not seen the Riders, but it sounds like it's not correct. R100 (as called out in the Philco service Bulletin PR-1135 for Code 121 and Bulletin PR-1298 for the 122) is an 80 ohm candohm unit (filament string ballast). The 46-200 Code 121 did NOT have a 14B6 in it.
The Model 48-200 has that tube lineup in the Rider's you are referring to. There also is no R100 filament string ballast resistor in the 48-200 because the IF tube has a 14 volt filament (14A7) instead of the 6.3 volt (7B7), the difference which R100 makes up.
Riders got it mixed up. There's the confusion.
Posts: 322
Threads: 62
Joined: Mar 2007
City: Toledo
State, Province, Country: OH
Chuck, Mallorys also shows the same tube line up for the 46-200 that I have: 7A8, 7B7, 7C6, 50L6, and 35Z5. So did Mallorys copy from Riders?
Might it be possible that Philco made a mistake when they labeled this radio? Pictures of the 46-200 match mine to a tee.
Posts: 1,703
Threads: 55
Joined: Sep 2005
City: Evanston, IL
Don't know about Mallory. I did some further checking and the schematic that Riders shows as the "46-200" is actually the CODE 125 version of the 46-200. My Production Changes for the Code 125 version reflect the two 14 volt tubes and omission of R100 in the fil string.
Your set, with that tube complement, is a Code 122 version. The changes from the original Code 121 are only the rectifiers and filter cap and the addition of dropping resistors R101 and R102. This permitted the use of a PM speaker. The new three section filter cap and two resistors were added because of the field coil elimination.
Chuck
Posts: 322
Threads: 62
Joined: Mar 2007
City: Toledo
State, Province, Country: OH
Thanks Chuck. Well at least Beitmans got it right. Just downloaded the schematic.
Posts: 322
Threads: 62
Joined: Mar 2007
City: Toledo
State, Province, Country: OH
Another question. There is a 120K resistor from pin 4 to pin 6 on the 35Z5. Pin 4 corresponds to B- and pin 6 is the same point as pin 4 of the 7A8.
According to the schematic it should be either a 47K or a 100K resistor. Is there another cgange I don't know about?
Posts: 322
Threads: 62
Joined: Mar 2007
City: Toledo
State, Province, Country: OH
Users browsing this thread:
|
Recent Posts
|
Philco 610B oscillator wiring
|
> The cathode as noted is wired directly to the ground side of the heater filament for that tube, not to the #17 and ...Radioroslyn — 08:12 PM |
HiFi (Chifi) tube amp build - but my own design.
|
Tim;
I noticed your post a little late, but I would take one of the junk sockets and try to break a chunk out of it wi...Arran — 08:07 PM |
Need to purchase some accessories for restoration of my Old Philco Radio
|
Here is a list of resources found in our online library that you might find useful. Mike's Gobs of Knobs email addres...klondike98 — 01:46 PM |
First Radio restoration
|
Hi Tubeman,
Welcome to the Philco Phorum. Phamily Phriendly Pfun with Phine Pholks Phull of Philco Phacts. (See a p...MrFixr55 — 12:33 PM |
First Radio restoration
|
You could post in the WANTED ADs section here on the Phorum and see if anyone has an RF generator that they want to sell...klondike98 — 11:55 AM |
Zenith H725
|
Good ideas, thank you Arrange and Rich. I have the adhesive aluminum foil already and can try that immediately.
More ...EdHolland — 10:18 AM |
Graphics for majestic 1050 dial glass.
|
Murf;
I found this thread on the ARF, the first photo has a pretty good view of the dial glass.
Regards
ArranArran — 01:12 AM |
Zenith H725
|
hello Ed,
how about that speacial tape used for ducting it's like foil or how about thin piece of
aluminum roof flash...radiorich — 12:19 AM |
Zenith H725
|
Ed;
One material that I have seen, but never tried for this was material for making exhaust gaskets, it's similar to ...Arran — 11:42 PM |
Zenith H725
|
I just remembered, I have some hi temp silicone rubber material which could do the trick. Or a piece of FR4 laminate. Th...EdHolland — 08:39 PM |
Who's Online
|
There are currently 1611 online users. [Complete List] » 1 Member(s) | 1610 Guest(s)
|
|
|

|