[Milsurplus] TCS in operation

[w8au at sssnet.com]

At 02:54 PM 2/21/2008, Military1944 at aol.com wrote:
>I noticed there is quite a spark when the contact is lifted, ie the 
>back emf off the 2 relays must be quite a bit. Thinking on the fact 
>the set is CW keyed via these relays then even at 12 to 15wpm there 
>are going to be quite a few clunk clicks on them. Has anyone 
>(bothered) to fit either a reverse diode or an RC filter across the 
>key line ? to help suppress these clicks and back emf voltages?

Ben:

I have done that.  The only effect I notice is that it lengthens the 
relay "on" time
by a few milliseconds (not measured).  The "back EMF" spike, when 
shorted by the
diode, appears to keep some current flowing in the relay coils, 
thereby lengthening
the ON time slightly.   It does not present any problem with 
operation.  If you are using a
BUG or keying device you might want to lighten the weighting compared 
to what you
used prior.

Have fun with the "old reliable" TCS.

Perry   w8au
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