[AMPS] Transformer choice

[Vic Rosenthal]

I've been reading the traffic here about transformers and power supply types,
with the intent of picking a transformer (the *last* big missing piece) for my 2
x 3-500z amplifier project.  To remind everyone, I'm intending to run it at
about 3kv, and I am aiming for about 1500 watts output, CW.  No bricks on keys
or rtty, but I do want reliable CW contest operation.

Looking through Dahl's catalog, I find this one:

=====================================
HEATH SB-220-3-7 EXTRA HD REPLACEMENT WITH 7 MIL C-CORE B-0393/ (SIDE MOUNT) 10
23 $225.00
PR) 117/234 VAC 60 HZ HI-LO TAPS S1) 860/1171 VAC @ 1.3A CCS
DM) HT = 6.000 WT = 6.325 DT = 6.281 MD = 3.625 MW = 4.000 WT = 23.1 LBS
======================================

I figure that this should be a conservative choice given the short-term duty
cycle of about 50% for CW, and of course the lower long-term duty cycle (taking
listening periods into account).  It is designed to work in a doubler circuit,
and I have 8 240 uf 450v caps available.

I've had some people recommend larger transformers.  Am I cutting it too close
here?

73,
Vic, K2VCO
Fresno CA



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