[MCARC] Linear Amps for HF

[Dennis Mason]

I suppose most everyone knows, but just in case, I have had a recent case of the Linear faults when they are first turned on and damage is done to the power supplies.  Un-protected, to the surge of current when turned on can be reduced by putting a module  inserted in the power line circuit before it gets to the diodes and caps.  Another solution more simple, is to add a 20 ohm 25 watt resistor in the high voltage (doubler center winding of the rectifiers and filter Caps).  My experience, was to repair one of the commercial circuit board inserted into the ac line to the transformer.  It burnt up the 2 surge resistors. Apparently was not designed to work in that big of Linear.  
They are available at Harbach Electronics. LLC., Soft-Start module.  But the resistors are 10 Watt, and probably should be 25 Watt for some linears.
Dennis

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