MOX operation of k2

[Charlie Kahwagi]

Hello All,
            Can anyone help with ideas on how to set up manual switching to Tx  in CW mode.  I wish to put the K2 into Tx without sending ANY RF to allow my Transverter time to run through it's fully sequenced switching.

At present every time I hit the CW key, a burst of RF gets shunted up the back end of the last receive amplifier stage in my transverter  for about 700ms before full Tx switching occurs in the transverter.
As yet I haven't  "blown" any devices up as I have placed Back -to-Back diodes to limit the RF voltage that the MMIC in the IF path sees.  However I feel there MUST be a more ele-gant solution! ( I am using my K2 for EME purposes, so it is more important to look after the LNA then the transverter IF chain)

It is a pity that there cannot be a delay placed in the software, or otherwise, on when RF actually begins to appear once the K2 is keyed.

Anyone driving a QRO amp. resolved this problem.  I suspect not too many running the 100 W version of the k2 to drive a 1500W amp would be happy to have the instantaneous RF on their output relays?

Perhaps I have missed something about this along the way?

Regards
Charlie
VK3NX
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[Don Wilhelm-3]

Charlie,

The easiest way to accomplish what you need is to inhibit the paddle input
to the K2 until your sequencer has completed its tasks.  A set of relay
contacts in series with the paddle lines will do that.  You may have to use
some kind of auxiliary circuits to start the sequencer - I have no idea how
that is accomplished in your station - if it is accomplished with a manual
switch then the solution already exists, take the "OK to transmit" signal
from your sequencer and use it to activate the relay.

For a more complex solution, take a look at my website
http://w3fpr.qrpradio.com article on PTT for CW.  That circuit handles SSB
and CW seamlessly (but again, you must have something of your own choice to
start your sequencer).

73,
Don W3FPR


> -----Original Message-----

> Hello All,
>             Can anyone help with ideas on how to set up manual
> switching to Tx  in CW mode.  I wish to put the K2 into Tx
> without sending ANY RF to allow my Transverter time to run
> through it's fully sequenced switching.
>
> At present every time I hit the CW key, a burst of RF gets
> shunted up the back end of the last receive amplifier stage in my
> transverter  for about 700ms before full Tx switching occurs in
> the transverter.
> As yet I haven't  "blown" any devices up as I have placed Back
> -to-Back diodes to limit the RF voltage that the MMIC in the IF
> path sees.  However I feel there MUST be a more ele-gant
> solution! ( I am using my K2 for EME purposes, so it is more
> important to look after the LNA then the transverter IF chain)
>
> It is a pity that there cannot be a delay placed in the software,
> or otherwise, on when RF actually begins to appear once the K2 is keyed.
>
> Anyone driving a QRO amp. resolved this problem.  I suspect not
> too many running the 100 W version of the k2 to drive a 1500W amp
> would be happy to have the instantaneous RF on their output relays?
>
> Perhaps I have missed something about this along the way?
>
> Regards
> Charlie
> VK3NX
>

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