
Manufacturer: General Radio Company (USA)
Model: 687-A, S#112
Vintage: 1935
Purpose: General Purpose
Condition: Rebuilt
Comments:
This 687-A was completely modified inside and the outside was riddled with extra holes and tape. I decided to gut it completely and mount a "modern" scope circuit inside. Now it can be used as a monitor scope at least. Therefore the inside is not worth any pictures. I tried to rebuild the outside as much as possible.
Only because it is such a rare and historically important unit, I spent so much time on it and post at least a few pictures of it.
Thanks to Allan Weiner, WBCQ, for sharing the manual.
Model: 687-A, S#112
Vintage: 1935
Purpose: General Purpose
Condition: Rebuilt
Comments:
This 687-A was completely modified inside and the outside was riddled with extra holes and tape. I decided to gut it completely and mount a "modern" scope circuit inside. Now it can be used as a monitor scope at least. Therefore the inside is not worth any pictures. I tried to rebuild the outside as much as possible.
Only because it is such a rare and historically important unit, I spent so much time on it and post at least a few pictures of it.
Thanks to Allan Weiner, WBCQ, for sharing the manual.
Documentation:
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