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jbljfan
12-13-2006, 05:38 PM
What cap value would one use where:
C1A=100mF
C1B=100mF
C1C=82mF
C1D=1mF
ref: http://www.jblproservice.com/pdf/LSR%20Series/LSR32LR.pdf

Thanks,
Mike

John W
12-14-2006, 09:09 AM
These capacitors are hooked in parallel so their total is the sum of the values:

283uf

mf = uf in this instance.

For biasing you are basically hooking two capacitors in series and applying a small charge where they come together.

The formula for two capacitors in series is Ctotal = (C1 * C2) / (C1 + C2)

You want to maintain the same capacitance of 283uf, so you need two capacitors with double this value, or:

two 566uf

Of course to get this value will probably have to parallel up multiple capacitors for each half.

If you plan on using film and foil capacitors get out your check book, and make sure you have room to put them all.

I checked on PartsExpress and using Solen Polypropylene you could get 566uf by using:

200uf + 200uf + 160uf + 3uf + 3uf
(bias charge)
200uf + 200uf + 160uf + 3uf + 3uf

jbljfan
12-14-2006, 11:15 AM
As a schematic newbie I was afraid that might be what I was looking at (I was hoping for an intermediate value). Thank you for confirming the 566 value.

Regards,
Mike