Can't find a schematic?

FrankB wrote:

You may need to get an approximate date of the set you are trying to find a schematic on and look at schematics by other companies about that time period.

A similar approach is to look for chassis with the same tube lineup. A good way to do that is with Sams' "Radio Industry Red Book," which gives the tube lineup for each chassis. I use the 1948 first edition because I collect only pre-WWII radios.

It can be either a TV or a radio. One person posted looking for a schematic, but it appears they left off part of the number.

Are you referring to a TV or a radio?
 
For radios I went to Universal Schematic Locator.
I came up with several:
Montgomery Wards
 
 BEITMANS VOL 12 (1952) PAGE 78-79
 
25WG1570B, .
25WG-1570B.
25WG1570C.
25WG-1570C.
25WG1571B
25WG-1571B
25WG1572B
25WG-1572B
 
RIDERS VOL 16 PAGE1
PURE OIL CORP.
5D25WG5025
 
Sams (i think they may be tvs)
Quasar a19t25wg-set612-folder2
Quasar a19t25wga-set627-folder3
Quasar a19t25wgl -set627-folder3
 
Wards over 30 serial numbers (too tired to type them all) they all have 25wg27xxx
 
There are other sources
Which aren't used as much or as popular.

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Factory service publications)
And like what you stated other brand names
Some other companies may even have the same chassis number .

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I CAN"T FIND A DARNED SCHEMATIC!

This happens to us all at times.
Extremely annoying and frustrating.

 So here are some things to try:

 The big chain stores like Sears, Montgomery Wards, Western Auto, etc. NEVER made their own radios or TV sets. They contracted them out.

 Now Wells Gardner I know for certain made sets for many companies as did Toshiba, Magnavox, and a few others.

You may need to get an approximate date of the set you are trying to find a schematic on and look at schematics by other companies about that time period. You may luck out and find one close enough to use, or if the "Electron Gods" truly smiled on you, the exact schematic by the company who made it. They often made the exact set for several different companies, just different model numbers and cabinets. Sometimes the only difference, especially in TV sets was adding more parts to the high end sets to include more features. The PC boards already had all the circuitry on them, awaiting the addition of the parts to make it a "Higher End" set.

Using Montgomery Wards as a prime example (Just tried to find a schematic for a poster here), the model number might be 25WGXXX- Indicating Wells Gardner most likely made the set.
 Little tell tale hints can help.  If you are really lucky, you may find the original tubes in the set to help. I once found a schematic for a Sears set close enough to use by finding it had the original Toshiba tubes in it, and that characteristic "Japanese chassis" look inside the TV. A Toshiba schematic did the trick.

IIRC there were many radio sets made by "Plant A" that were just radio chassis sold under many names, just different cabinets brand names, and styles.
 
Hope this info can help.