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replacing capacitors
4/20/2003 9:56:32 PMsean
Hello , is a 22 uf cap close enough to replace an 8 uf cap?
4/20/2003 10:05:48 PMNorm Leal
Hi Sean

In most cases a 22 uf will be better than 8 uf for filtering hum. If used right after an 84 or 7Y4 rectifier I would use a 10 uf rather than 22 uf. Larger caps increase surge current. These tubes can't take much. No problem after an 80 rectifier. Be sure voltage rating is equal or more than original cap.

Norm

:Hello , is a 22 uf cap close enough to replace an 8 uf cap?

4/20/2003 10:52:12 PMsean
:Hello, yes the cap(s) (8+8) are after the 80 rectifier tube. The dry electrolytic does say 630 volts, is this really necessary?. The ones I have are 450 volts
:
:Hi Sean
:
: In most cases a 22 uf will be better than 8 uf for filtering hum. If used right after an 84 or 7Y4 rectifier I would use a 10 uf rather than 22 uf. Larger caps increase surge current. These tubes can't take much. No problem after an 80 rectifier. Be sure voltage rating is equal or more than original cap.
:
:Norm
:
::Hello , is a 22 uf cap close enough to replace an 8 uf cap?
4/21/2003 12:12:11 AMsean
::cap serge voltage is 385 volts
::
::Hello, yes the cap(s) (8+8) are after the 80 rectifier tube. The dry electrolytic does say 630 volts, is this really necessary?. The ones I have are 450 volts
::
::Hi Sean
::
:: In most cases a 22 uf will be better than 8 uf for filtering hum. If used right after an 84 or 7Y4 rectifier I would use a 10 uf rather than 22 uf. Larger caps increase surge current. These tubes can't take much. No problem after an 80 rectifier. Be sure voltage rating is equal or more than original cap.
::
::Norm
::
:::Hello , is a 22 uf cap close enough to replace an 8 uf cap?
4/21/2003 12:35:11 AMNorm Leal
Hi Sean

Your 22 uf @ 450 volts will work. Original caps were probably rated 350 volts with 385 surge. That 630 volt rating must be paper or mylar coupling caps? Not a reasonable electrolytic cap rating.

Norm

:::cap serge voltage is 385 volts
:::
:::Hello, yes the cap(s) (8+8) are after the 80 rectifier tube. The dry electrolytic does say 630 volts, is this really necessary?. The ones I have are 450 volts
:::
:::Hi Sean
:::
::: In most cases a 22 uf will be better than 8 uf for filtering hum. If used right after an 84 or 7Y4 rectifier I would use a 10 uf rather than 22 uf. Larger caps increase surge current. These tubes can't take much. No problem after an 80 rectifier. Be sure voltage rating is equal or more than original cap.
:::
:::Norm
:::
::::Hello , is a 22 uf cap close enough to replace an 8 uf cap?



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