[Central-Electronics] 600L Plate Overload relay

[Robert Nickels]

The bad news is, the little tensioning spring that sets the trip point 
of the plate overload relay in my 600L broke in two.   The good news is 
I will no longer beat my head against the wall trying to figure out why 
it keeps tripping unpredictably!

I know it's made by Guardian but I can't make out any of the writing on 
the coil - wonder if anyone knows how it's adjusted, i.e. how much 
current must flow through the coil before it causes the relay to trip?   
   I'm thinking maybe 2X the max amount of normal plate current would be 
about right?   I'm going to try to fix it with a new spring.

On a happy note - I've successfully used the 600L with my little Retro75 
2-watt AM transceiver with great results.  In fact I had to attenuate 
the drive to hold it to about 80 watts of carrier to keep the 813 happy, 
even though it will do almost twice that.  The 600L is one impressive 
amplifier.

73, Bob W9RAN