[Elecraft] Paddle input with Y connector OK?

[Joe Subich, W4TV]

> Is there any reason I shouldn't make a "Y connector" so my CW paddle
> can be input to the K3 and another radio (or external keyer)?

Yes. Most rigs have a logic level input with pull-up.  Some are CMOS
(12V) others are TTL and all have some voltage that could cause
issues for another radio.

If you do a "Y" connection, at a minimum you should use diodes to
isolate the radios.  However, if one of the radios uses low power
CMOS logic even a silicon switching diode will introduce too much
voltage offset for the keyer to work properly.

73,

    ... Joe, W4TV


On 3/27/2011 5:50 PM, Barry wrote:
> Is there any reason I shouldn't make a "Y connector" so my CW paddle can
> be input to the K3 and another radio (or external keyer)?  Yes, only one
> will be on at any given time.
> Tnx,
> Barry W2UP
>
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