[Elecraft] K2: KPA 100 Capacitor Specification?

[Don Wilhelm]

Bill,

While all you say is true, the inductive 'kick' should not be larger 
than 2 times the applied voltage.
That is still a safety margin of more than 2.

73,
Don W3FPR

Bill Miner wrote:
> Don & John,
>  
> When a relay is de-energized the voltage developed from the collapse 
> of the magnetic field can exceed the source voltage by many times. 
>  
> In the past it was the convention to put a reverse polarity diode 
> across the relay coil to absorb the energy when the relay is de-energized.
>  
> Since Elecraft dose not use the reverse polarity diodes in any of 
> their kits I assumed this function was built into the relay driver 
> chips.  If not, perhaps a higher voltage rating for C13 and other 
> capacitors like it is called for? Or could the relay driver U2 be 
> defective?
>  
> 73,
> Bill - K6WLM
>
>