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Model 90 tone control help # 03137
#6

(03-24-2016, 07:57 PM)morzh Wrote:  Single 47 registered in my mind.....but all versions are there.

Note: The first cap I use of a lower value. Otherwise from the very first turn of the knob the highs almost disappear.

It looks like the 03137 control incorporates the change you suggested. Do you recommend an even smaller value?   I hope my math is right.

03137 tone control
Pos 1.  .006uf. (.01uf in series with .015uf)
Pos 2.  .015uf. (.01uf shorted out in series with .015uf)
Pos 3.  .025uf (.01uf in parallel with .015uf)

4037-A tone control
Pos 1.  .015uf
Pos 2.  .025uf 
Pos 3.  .035uf


There have been several errors in the schematic and parts list.

1.  Wrong tone control listed. Parts list says 4037-A but it is 03107
2.  There is an extra bakelite cap accross the choke (item 55). It is not on the chassis diagram or schematic.  I found a mention of this by another member in an earlier post.
3.  Item 38 is listed as a 3903-P cap.  The part that was installed was originally stamped 3903-R but there is another stamping on top of it making it difficult to read.  That actual configuration doesn't match any of those listed for 3903s. 
4.  The metal can caps were not correct which is mentioned in the tech notes.  


It would be pretty difficult to figure this stuff out without this forum.  THANKS!

Jim


Messages In This Thread
Model 90 tone control help # 03137 - by Jbaker - 03-24-2016, 03:54 PM
RE: Model 90 tone control help # 03137 - by morzh - 03-24-2016, 04:35 PM
RE: Model 90 tone control help # 03137 - by morzh - 03-24-2016, 07:57 PM
RE: Model 90 tone control help # 03137 - by Jbaker - 03-24-2016, 10:33 PM
RE: Model 90 tone control help # 03137 - by morzh - 03-25-2016, 09:34 AM
RE: Model 90 tone control help # 03137 - by RodB - 01-12-2024, 10:44 AM
462ron - by 462ron - 01-13-2024, 08:55 AM
RE: Model 90 tone control help # 03137 - by morzh - 01-14-2024, 02:08 PM
462ron - by 462ron - 01-15-2024, 09:26 AM



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