FW: [Boatanchors] CAPACITORS

[brian goldsmith]

-----Original Message-----
From: W4AWM at aol.com


This may be a bit off the subject, but can anyone tell me how to check a 
motor starting capacitor without substitution. I don't have a spare.
Capacity is 
9pf @ 250VAC.

73 and thanks,

John,  W4AWM

***** It almost certainly is NOT 9 pF,more likely to be 9 microFarads (or 9
uF).
Simplest method of testing is to use a high voltage DC supply from an old
radio capable of providing at least 350 Volts,use two 220V series connected
low wattage incandescent lamp to limit the current ,then charge the
capacitor up.Watch the lamp,if it goes out,most likely the cap is OK,if the
lamp stays illuminated to even a slight degree then the cap is leaky.If you
do not observe any light at all from the start of the charging then the cap
is either fully charged (discharge it with a resistor,never a direct short)
or it is open circuit.

Brian Goldsmith.