At a surplus sale, a friend picked up a large number of old circuit boards, probably 30-40 in all. Here's the box:

Box of circuit boards

All the boards seem to be made by the same manufacturer and probably come from the same device. Notable components include motors, dials, and op-amps (LM741CN).

Close-ups of some of the boards:

Board with motors

Board with diodes

and the back side of the motor board:

Backside of board with motors

The most notable and obvious feature of these boards is the logo:


This logo is on the back of every PCB, although I could not identify it with either reverse image search or by searching for the description.

Can anyone identify the manufacturer? Maybe narrow down what era of technology this is (probably 1970-1980 but that's a big range)? Or what this device might have been? It's to satisfy a burning curiosity :)

  • 2
    \$\begingroup\$ Determining the manufacturer and what devices they are is unlikely possible unless they're labelled. Date codes on the ICs visible to '76-'77. The last picture is probably a PCB maker's mark. Your curiosity is probably unsatisfiable unfortunately. Why would anyone buy a box of old boards of unknown origin? \$\endgroup\$
    – Matt Young
    Commented Sep 16, 2015 at 20:11
  • \$\begingroup\$ My friend has a fascination with older technology, and likes to snap up these sorts of things and rework them into art projects. For example, he made a few lighting fixtures using these old circuit boards as lampshades. \$\endgroup\$
    – nneonneo
    Commented Sep 16, 2015 at 20:13
  • \$\begingroup\$ maybe Fluke or Tektronix judging by the custom part numbers and vintage... note photo #2 shows a Motorola chip with a custom topmark starting with 551- if you can figure out which manufacturer used 551- as prefix for Motorola manufactured components, that's a start. Maybe browse the online boat anchor manual repository? \$\endgroup\$
    – MarkU
    Commented Sep 16, 2015 at 20:26
  • \$\begingroup\$ @GregoryKornblum: Heh, I would, except I am pretty curious about the parts too. \$\endgroup\$
    – nneonneo
    Commented Sep 16, 2015 at 20:40
  • 6
    \$\begingroup\$ Two adjustable inductors are labelled D and C#. Are there similar boards with other labels, say from A to G?. If not, I'm sorry but you don't have a full set... However at this point I would be looking for electronic organ manufacturers with J in the name, active in the mid-late 70's. Expect those boards to be master oscillators; others to be frequency dividers by 2,4,8 etc for the octaves, and possibly analog filtering and sound shaping... \$\endgroup\$
    – user16324
    Commented Sep 16, 2015 at 21:35

1 Answer 1


Those boards appear to be parts of an electronic organ. The image below is from an from an eBay auction - described as a "Kimball Organ Tone Generator/ Divider Board B & C". It looks very similar to yours (same number and order of pins on the edge connector, similar coils with almost identical labels).

enter image description here

  • \$\begingroup\$ Interesting...Kimball was known as Jasper Corporation for a while (although they changed their name in 1974). I wonder if that logo might be J for Jasper... \$\endgroup\$
    – nneonneo
    Commented Sep 16, 2015 at 22:02
  • \$\begingroup\$ beat me to it! kimball.com/kimball_history.aspx \$\endgroup\$
    – user16324
    Commented Sep 16, 2015 at 22:02
  • \$\begingroup\$ Searching for "Jasper Electronics organ" produces a string of patents, some with circuit diagrams which might be useful, but no logo so far... There are serious electronic organ enthusiasts who may be able to help. \$\endgroup\$
    – user16324
    Commented Sep 16, 2015 at 22:06
  • \$\begingroup\$ Strange, I have a ton of these boards as well! Picked them up from a scrapped electric organ at the local dump... I have the full assembly of the cards with the large coils on them, There are two notes per card, and they plug into a wire wrap backplane. The ferrite slugs in the coils are glued in place. \$\endgroup\$
    – user115645
    Commented Jul 2, 2016 at 16:17

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