Capacitor ID numbers wrong? (AG-1980/5710)
 

I'm preparing to re-cap my AG-5710. I've got the service manual for both the AG-1980 and the AG-5710. I also have the wonderful capacitor list download from here.Sadly, few if any of the Cnnnn ID numbers in the documentation or the list actually match what's on my circuit boards, even though the board ID's do match!


I've searched and not found a discussion of this issue here.


QUESTION: am I missing some kind of translation table, or do people simply ignore the ID codes and only look at actual volts/capacitance/etc?

Parts list and schematic numbers frequently (but not always) are of the form C#### and often the first one or two digits reference the board on which they are to be found.
The circuit boards often use fewer digits and may omit the digits that refer to the board.

The C#### numbers on the schematic and parts list should match. The number on the board may not be an exact match; e.g., C6751 on the parts list should correspond to C51 on the mic jack board. But there may be exceptions.

When replacing components be sure values match, do not rely on the "C" numbers only.

At the very least, it's true that on the board it may have a much shorter number.My first several random samples also showed that the number may not match even a little.
Hopefully there's an approximate match of quantity of caps, and values.
I'll try to record a reasonably accurate table of reality vs theory on this as I go ;)

Also keep in mind that there may be slight variations in boards. These variations may not be in the original FSMs. In some cases they would be shown in addenda pages added to the manuals later on. Consider the FSM a guide that requires some interpretation of details. The factory techs would have covered this in their training, and perhaps also covered in some of the Radio/TV repair trade press.

In another AG-1980 thread it was noted that there are at least two variants of the Y/C board. Mine came from the factory with a couple components added after production of the board including (from memory) a jumper wire and ceramic cap. Another old thread on the AG-1980 has photos of it.

When I did my Y/C and other board SMD caps several years ago I bought parts based on the parts list, and replaced per the values marked on the part removed. Some of the manual part numbers were discontinued, I ordered replacements based on the value, physical size, and in some cases special features such as low ESR.

Good luck with your project.

Being almost done with my component catalog, I've learned three other factors:

• Yes there are board variations. AFAIK they are generally marked as version numbers (eg my Timer is VEP07800-B not -A)
• Yes there are additional "tweaks" - I have several caps, particularly on the back side of some PCB's, that are unlabeled and clearly not part of the original design.
• On the main PCB, there are so many components that the board is divided (virtually) into about a dozen "Series" (eg "Ref No 2000 Series") Each section absolutely can have identical component ID's (eg three different C31 caps, 16v 10uF, 16V 100uFG, 50V 1uF.)

To wrap up this thread... I just created a new thread to upload a spreadsheet and other data: I've fully documented the boards, the series, the physical markings and how they match to the service manual / schematics / parts lists.

Hope that's helpful to someone someday.