Service Data- Errors- & Info.

Quite the progression Frank. A good read.

Funny, when you mentioned Muntz at the end. That immediately brought back the memory of me in my younger years listening to the musical jingle that played constantly on the radio..... "There's something about a Muntz TV, in oh so many ways, etc." 

Service Data Errata:

 Sams quite often had errors in their schematics. If you subscribed to their POM Program (Photofact of the Month) they would include corrections. These did not appear in the normal Photofact folders, to my knowledge when you just bought one folder from the supplier. The only way I got the correction sheets was when I bought out a shop that had the subscription to the POM program.
In later years Sams appeared to just copy the OEM service manuals. This seemed apparent on their VCR and Computer service data. 

Early Sams contained as many as up to 30+ schematics. In later years, you were paying ($80.00?) a month for a single folder covering 1 set. many shops dropped the POM at this poing. It was cheaper to buy the service data from the OEM, which would include any errata sheets and run change info.

Now on the Riders Radio and their TV manuals, I personally never saw any errata sheets. Basically Riders appeared to be just copies of the mfgr's. schematics. 

  Originally Sams would buy the models of radios and TV sets, then reverse engineer the circuitry to make the manuals.  This WAS very labor intensive and costly to buy all the models of TV's, radios, phono's and amps. I m not sure when they stopped this practice.

   Sound Design OEM service manuals were apparently exact copies of the Sams schematics.  I have some Sound Design OEM schematics, and they have the same layout style that Sams used. Once you got used to Sams method of laying out the circuits, it was very apparent. From an economic standpoint it does make sense.

  Most mfgr's. had their own specific way of laying out the circuitry in the service data. Most of the time I did prefer the Sams layout, as it seemed to me to be easier for me to follow.

 When it got to the VCR,s and Rear projection TV sets with the multiple pages for each set it got to be a real PITA as it meant flipping from one page to another to try to trace out the circuit paths.

 And don't even get me started on the MicroFiche service manuals. What an idiotic idea! Hauling a microfiche reader with you on a service call and having to drag it into the customers home was totally insane. If you wanted to print off the microfiche  manuals you either had to buy an extremely expensive reader - printer that was very large, (About 3' square), heavy, and VERY expensive, or take the fiche to a library to have them printed off there. (Oh the joys of having to align and tape together up to 30 + pages to read the printed out schematic, plus the library that I used charged by the page. Then you had a schematic that could be up to 6+ feet square. And yes, I still have the service manuals on Fiche, and the reader-printer.) I doubt that the libraries even still have the Fiche printer- readers anymore.

  Zenith (The ORIGINAL, not the LG) went to the "Sight and Sound" training manuals before computers were really around. Nicely done training manuals and you listened to the audio tape as it walked you through the instructions.

   Training manuals progressed from paper to Video tape. Some were very well done and some were....well...poorly done.
   Example: Magnavox "training" manuals were generally a rehash of the  exact same repair, moved to the next model training tape. "Dead set on Chassis XXX; Check diodes in power supply. Here we find CRXXX is shorted. Replace diode". In the mass of Magnavox/PCE training tapes on video I never once found a training service tip for repair that I ran into in the the real life world. Cookie cutter "training" tapes.

Otoh, The best training info were the RCA paper training manuals. They went into exacting detail on how the circuits worked and troubleshooting information. They saved my bacon a few times, by using them with the schematics and following both. The info on them for the CTC 176-179 for aligning the tuner after replacing the blown EEPROM and setting the EEPROM parameters was pretty easy to follow, and was very exact, if time consuming, in each step.  Zenith was pretty good also.

 Then in a stroke of "wisdumb"  the OEM's started putting the service manuals on disk, which required a laptop to read them for doing in home service, or print the entire schematic out at the shop before going on the service call. Trying the follow the schematics on a laptop or desktop computer was, at least for me, a real nightmare.  
 This nightmare  was then multiplied when the outside tech needed the disk for a service call and the schematic you needed for the set you were in the middle of working on in the shop was on the same disk. PCE - in order to read the disks, you had to have a special password embedded in your computer too. AARGHHHHH! You couldn't copy the schematics to your computer memory at that time, as it required the original disk, just like some computer games required. Oh, and IIRC there was a "fee" for the 2nd password to read the disks on the techs laptop too from one company also.

They went from paper to 5-1/4" disk to the 3.5" disks, then to the CD Rom, and finally to the DVD's. Likely they are on USB thumb drives now, or only downloadable online. One tech had to upgrade his laptop 4 times out of his own pocket just to be able to read the service data in the field. 


Also Many manufacturers OEM service data would contain errors. If you were a subscriber to the OEM service data, you would receive correction sheets . I found this to be the case with RCA, Zenith, and "Magnavox/PCE/Phillips/Sylvania/Crosley" (Basically all the same chassis in the different brand names in later years, but with some differences. This was when Phillips/PCE owned the entire lines.

Often when the circuit boards were made for PCE products, Sears, and likely others- The circuit boards contained the traces for the "higher end" sets, minus the parts. So if you are working on a set with many vacant areas with thru holes and traces, this is the most likely reason.

Many sets, especially the lowest end ones, were built with only the minimal number of parts to meet the contracts specifications. (This brings back memories of "Mad Man Muntz".) If you wanted, say remote control, those parts would be added at time of mfg., but the set would cost more. Sometimes sets were made with specific parts that were only available from the retail sellers parts dept, Sears for example was the best example of this that I found during the years I serviced TV sets.