[AMPS] Transformers

[Peter Chadwick]

Rich says:

>?  Many models of Henry amplifiers do not use a peak discharge-current 
>limiting glitch resistor is series with the hv positive lead.  Most of 
>the hv transformer failures I have heard of in Henry amplifiers were 
>associated with a noisy arc in the RF output compartment.  .  

Rich, what was the failure mode? Open circuit, shorted turns, or insulation
breakdown?

My only experience with HV xfmr failure has been insulation breakdown. That
was using an (unpotted!) 1200 - 0 - 1200 in a FW bridge, in a remote
controlled  amp out in the garage. 

Should have known better - 1) xfmr not intended for that many volts from
winding to frame. 2) using an unpotted xfmr in a damp location.

It was a risk that didn't work out. However, it leads me to concur with Rich
about the desirability of potting - unless you can get a mil grade
hermetically sealed oil filled job (that isn't leaking!)

73

Peter G3RZP



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