circuit diagrams for National electric organ SX-3500R bought around1978

I recently turned on my electric organ after many years of not doing so, and find that the 16' tabs don't work, ie if only the tab is turned on, then the keys don't play any sound. My brother, now 85, used to be an electric organ and tv service/repair man, but had gotten rid of all his service manuals/circuit diagrams except for his wife's wulitzer, he forgot about my National. (National electric organ SX-3500R bought around1978),
He has looked at mine, but says he needs the circuit diagram.
Can anyone help please?
kind regards,
Abbe

Hi,
that also seems to be referred to as a Panasonic / Technics - made one.

None of the normal schematics sites I know of have any reference to that model, unfortunately...

This place appears to list a service manual in their collection, but presumably you have to contact them & purchase a photocopy, or something..

You could also try asking on one of these dedicated sites:

That one has the user manual visible;

It's a problem with a lot of pre-internet equipment; there were only ever paper copies of manuals, so nothing on line unless someone scans it and posts to a free site..


ps. Just try operating ALL switches, drawbars and controls a dozen times each - it's common for exposed contacts in switches to tarnish when unused, then the slightest movement or vibration can move the contacts to a tarnished area and things distort or stop working. Just operating the switch to scrub the contacts against each other can often clear that type of problem.

If you find any causing a problem, a tiny amount of 3 in 1 oil applied carefully, or a dedicated cleaner/lubricant such as Deoxit, can make a tremendous difference. They block air to prevent corrosion and reduce wear.