[Elecraft] Sequencer keying with K3/XV-144 without rigblaster?

[ANDY COOK]

To make this all simpler I normally run the transverter as the LAST box to be sent to transmit (ensuring that RF switching is disabled!). So Rig->sequencer->Tx relay->PA bias->transverter. This may hot switch the transverter, but that's rarely a problem in reality with the low powers and enables the system to be built with all the normal VOX / Semi-break in facilities on the radio working normally. 
 
Now just need to find out why some of the Amphenol N-type relays used for high power switching have got into a state that can take up to 0.5 second to release after volts have gone. Maybe they've got magnetised - they were originally 115V AC relays re-wound for 28V DC, but one has already bitten the dust from the consequent hot switching where the sequencer didn't figure on needing to take 1 second to changeover!
 
73,
 
Andy, G4PIQ
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Brian Alsop wrote :
I guess I'm missing the boat on this discussion.  

I thought all high power VHF ops used an external sequencer board that 
did the following type of thing.
RX to xmit:
1) Bypass the mast mounted preamp, wait a bit
2) Put the amp in the tx mode, wait a bit
3) Put the xvtr in the tx mode, wait a bit
4) inhibit the RF output from the rig until 1-3 are complete.

With a relay based system 1-3 could easily be 60ms or more.

Going to receive does a similar thing --i.e. unkeying the various 
components with delays..

You're not going to get his set of multiple delays from the K3.

There are external sequencer boards available as kits for about $20.  
The K3 has an inhibit line for such use.

And yes, the big guns do have difficulty in the bang-bang contest 
mode.   You call them once and occasionally get the comment,  I'm not 
getting your call, my sequencing hasn't completed.

73 de Brian/K3KO
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