Duty Cycle on the K144XV transverter?

[James Rogers]

I am going to be running FSK441 on 2M meteor scatter and wondering what
the duty cycle is on the transverter in my K3.  Getting ready to start
searching for an amplifier.

73s Jim, W4ATK
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[Lyle Johnson]

Jim,

As with nearly all transmitters, it is a matter of heat.  If you have
adequate cooling on the left side of the K3, then the internal
transverter will be capable of a very high duty cycle. If it is blocked
and in a warm room, then the duty cycle will be significantly lower.

You might want to monitor the side panel temperature and run the unit
into a dummy load and find out the heat profile for the duty cycle you
expect to run in the ambient environment of your particular station.  
Vary the power output and/or cooling (a fan, for example) and see how
that affects it.

73,

Lyle KK7P

> I am going to be running FSK441 on 2M meteor scatter and wondering
> what the duty cycle is on the transverter in my K3.  Getting ready to
> start searching for an amplifier.
>
> 73s Jim, W4ATK

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[Oliver Dröse]

 
Hi Jim,
 
I have used my K3+K144XV extensively on a 2 m Meteor Scatter expedition last year. Besides high ambient temperature during the expedition also the K144XV develops heat quite quickly. It does not take longer than 5-6 WSJT transmit cycles for it to get warm enough it starts reducing output power. The longer it runs, the worse the power reduction (my one started at 9 watts out and settled at about 5.5 watts after half an hour running FSK441). What helps a bit is a fan oriented on the left side of the radio as the K144XV uses the side panel for "cooling". Even better is not to run the transverter at full power out. So as you are just starting searching for an amp I'd suggest to look for one that just needs 5 watts input and drive the K144XV at that level. Takes away a lot of stress from the finals, too, I'd suppose. But still a fan might be useful if you'll do it for a few hours (like I did).
 
73, Olli - DH8BQA
 
 

> Jim Rogers <[hidden email]> hat am 24. Juli 2014 um 15:18 geschrieben:
>
>
> I am going to be running FSK441 on 2M meteor scatter and wondering what
> the duty cycle is on the transverter in my K3. Getting ready to start
> searching for an amplifier.
>
> 73s Jim, W4ATK
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]

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