[AMRadio] 813 Final Problem

Jim Tonne Tonne at Comcast.net
Thu Mar 19 14:08:35 EDT 2015

Assuming you don't have an actual modulator connected yet,
only the modulation transformer, short the modulation transformer

Of course when you get the modulator running later some time,
be sure to remove the short  :-)

- Jim Tonne W4ENE

On 3/19/2015 1:45 PM, Paul Baldock wrote:
> I am building a 15 meter 2 x 813 class C final. HV is 2200V. With 16mA 
> grid drive I can comfortably get 400W (and more) out.
> Every thing works fine until I insert the Mod transformer secondary in 
> the HV lead to the PA. NOTHING is connected to the input (audio) side 
> of the transformer. When I apply rf drive to the PA my High Voltage 
> connectors arc over. It seems this must be caused by some sort of 
> inductive spike. Any suggestions?
> - Paul  KW7Y

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