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capacitor question
7/2/2008 10:04:37 PMdel in MN
My schematic shows a 100 mmf capacitor from the CT of the Audio Output transfformer to ground. How do I read 100 mmf on capacitors?
7/2/2008 10:15:54 PMDoug Criner
The modern way is: 101 (= 100pF = 100uuF).
Doug

:My schematic shows a 100 mmf capacitor from the CT of the Audio Output transfformer to ground. How do I read 100 mmf on capacitors?

7/2/2008 10:16:03 PMdel in mn
The schematic also shows capacitors with just the number 10 or 100 with no voltages shown. This is an auto radio Lincoln 5BH. I need to know more about what the 10 or 100 means and voltages? Thanks
7/2/2008 10:28:16 PMdel in MN
More: I have orange drops labeled 122K 630 V. How is this read in MF? Thanks.
7/2/2008 10:37:08 PMDoug Criner
122 = 12 x 10^2 nF = 0.0012 uF. "K" refers to the tolerance (10%).

When all else fails, you can measure their value with a capacitance meter.
Doug


:More: I have orange drops labeled 122K 630 V. How is this read in MF? Thanks.

7/2/2008 10:29:15 PMDoug Criner
The voltage rating may not be shown on very small caps, because of limited space maybe? The voltage rating might be shown on the parts list. Otherwise, you can examine the schematic and guesstimate the maximum voltage that could appear across the cap.

Or, just use a reasonably large voltage rating for replacement caps, e.g. >500V.

If the schematic shows just 10 or 100, you'd need to see what it's doing the the circuit or possibly go by the physical size of the cap.

10 might mean 10uF if it's a filter cap in the power supply section? It might mean 10uuF, except I've never encountered such a small value in radios. nF (nano farad) nomenclature wasn't used in old radios, and even today seems to be a European style.
Doug

:The schematic also shows capacitors with just the number 10 or 100 with no voltages shown. This is an auto radio Lincoln 5BH. I need to know more about what the 10 or 100 means and voltages? Thanks

7/2/2008 10:37:39 PMdel in mn
The schematic instructions say micro micro farads at 200 VOLTS. But tell me how I read micro micro farads using a decimal or whatever. Thanks, Doug.
7/2/2008 10:43:31 PMDoug Criner
uF = 10^-6 F (one millionth of a F). uuF = 10^-6 uF (one millionth of a uF).

1 uF = 10^6 uuF.

uuF = pF. uuF is no longer used - pF is now preferred terminology.
Doug

:The schematic instructions say micro micro farads at 200 VOLTS. But tell me how I read micro micro farads using a decimal or whatever. Thanks, Doug.

7/2/2008 10:48:27 PMdel in mn
Thanks, Doug.
7/3/2008 12:05:10 AMMarv Nuce
Doug,
uuf is 10 to -12th farads.

marv

:uF = 10^-6 F (one millionth of a F). uuF = 10^-6 uF (one millionth of a uF).
:
:1 uF = 10^6 uuF.
:
:uuF = pF. uuF is no longer used - pF is now preferred terminology.
:Doug
:
::The schematic instructions say micro micro farads at 200 VOLTS. But tell me how I read micro micro farads using a decimal or whatever. Thanks, Doug.



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