[Boatanchors] TCS Tx & Rx ... CORRECTED

[J. Forster]

Bill,

Did you see the correected message? It looks like the reflector barfed?

-John

==================




OOPS!! WPM, not CPM. Scratch previous message.

--------------

Another poster opined it might delay the release 100mS. That is easily
measurable with an electric stop clock, let alone a any digital
multifiunction counter. No atomic clock needed.

Also, 25 wpm at the average of 5 characters per word is about 400 mS per
Morse character, so 100 ms per release is certainly significant, since all
characters, except E and T have at least 2 releases.

It is certainly possible for an experienced operator to unknowingly
correst for this delay by releasing the key a fraction of a second early.

The actual release time depends on the L/R time constant of the relay, and
the ratio of the applied pullin current to the dropout current. Not
knowing any of these, it is impossible to determine the actual drop out
time of the relay.

If you want faster relay dropout and spike suppression, you would be
better off with a properly designed series RC snubber.

-John

==============


----------

> John Forster said:
>
> I'm no CW op but I'd expect the diode would lengthen the relay release
time, maybe quite a lot.
>
> -John
>
> Hi John,
>
> Some passive parts across the key might have a noticeable effect like
that but the backward diode doesn't have any timing effect. If there is
one it would take lab equipment (atomic clock?) to measure it. At morse
code keying rates any stretching that might be there is 'virually'
nonexistent. And..it *DOES* get rid of that spike induced when the
magnetic field from the relay coil collapses. It's highly recommended in
solid state circuits to preserve keying transistors that are used to
energize relays.
>
> 73,
>
> Bill  KU8H
>
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