[sdiy] Inductors? Cloning CR-78 Drums

[allanjhall at lineone.net]

Hi,

I'm trying to clone the Roland CR-78 drum machine voice board, but there
are some inductors used that I'm not sure of. Most voices seem to use tuned
circuits, with an inductor and capacitor in parallel between the collector
of a transistor and the positive rail. In the cymbal, guiro and metal beat
the inductor value used is 45mh, which is still easily obtainable.

However, in the Claves and Rimshot the item is identified as 3R both on
the schematic and it is printed on the inductor itself, along with DA? 
I've measured the resistance and its 38 ohms. They are a ferriite bobbin
with a coil inside, about 3/4 inch in size. In the Tambourine circuit a
similar item is used, but it identified as 1R and has resistance of 3 ohms.

Can anyone shed some light on these components and suggest some equivalents
that would work?

Find the CR-78  voice board schematics here http://www.etek.chalmers.se/~e5he/cr78kassa/cr78p13a.jpg
and here http://www.etek.chalmers.se/~e5he/cr78kassa/cr78p13b.jpg

Many Thanks,
Allan

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