I did upgrade the filters with a new set of Mallory's which are exactly the
same size as the originals except they are rated at 680uf/450v instead of the
210ufd that came in the amp. Since the amp was built in 1986 I thought it was
time to replace the filters. By my calculations that reduces ripple from about
12% down to less than 4%. I used the assumptions of 1950 volts at 1.5 amps
with a total filter factor of (680uf/6) = 113ufd.
7.5[mS] * 1500[mA] / 113uF = 99.5575Vp-p | {*Ø.707} = 70.3872Vrms.
70.3872/1950 (*100) = 3.61% ripple.
I used the Mallory DCMC series. The part number is DCMC681T450AC2B (680ufd @
450VDC, 1.375" Dia. X 4.125" High). I ordered them from Newark. They are
physically identical in size.
Craig, W9CLA
-----Original Message-----
From: Steve Gehring [mailto:steveg@mtaonline.net]
Sent: Thursday, May 25, 2006 6:07 PM
To: amps@contesting.com
Subject: [Amps] Current P/N and Source for 374A or 76A Capacitive Input HVCaps?
Hi All,
Has anyone replaced the six 76A or 374A capacitive input filtering caps in
their Alpha 374A or 76A HV power supply lately? The original values are 210
and 180 mf at 450 wvdc. If so, could you supply me the part numbers and
source for these similar and readily replaceable units? Obviously, the
equalization resistors will be replaced, too. I'll have to contact Rich for
those...
Thanks and 73.
Steve, NL7W
Palmer, AK
--
No virus found in this outgoing message.
Checked by AVG Free Edition.
Version: 7.1.394 / Virus Database: 268.7.1/348 - Release Date: 5/25/2006
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|