[R-390] C327 checks

[Bill Riches]

Checking out an R390a that had low intermittent sensitivity below 8 mhz.
Replaced C327 and sensitivity came up to less than 1 uv.  Checking osc
output at J221 as measured with 10 db probe and Tek 465 is now 28 vpp.
Before changing C327 voltage varied between 5 to 15 vpp.  

 

Checked out cap with a Sencore Z meter.  Cap would change between 35 - 70
pf.  Checked for leakage - 200 volts - no leakage however capacity read 105
pf after being zapped.  A day later cap was varing as before.  Zapped it
again and 103 pf.  Then sprayed freeze-spray on it and it went bad again.  I
think the cap is faulty!

 

73,

 

Bill, WA2DVU

Cape May