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KX2 in FT8 mode - heat?

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N1EU

KX2 in FT8 mode - heat?

I'd appreciate hearing from others who are using their KX2 in FT8 mode in
terms of your experience with power output and acceptable PA heat level.
The reason I ask is that I'm running 5W on 40M with the rear foot down (rig
tilted up) and I'm seeing the PA temp reach 60deg C in ordinary qso'ing
(i.e., xmit for 12 sec out of each 30 sec period) with low SWR. How much
power are you running? Are you using extra cooling of any type?

Thanks & 73,
Barry N1EU
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Tommy

Re: KX2 in FT8 mode - heat?

Barry,

I run 10w through my KX2 with the back leg down to allow for
airflow and don't find heat to be an issue. I'm not TXing all that much,
I'm a hunt & pounce type with occasional CQing. In the summer I ran a
small fan over it to help a bit. No issues for me. I normally see it get
to the mid 40's c. 1:1 swr's.

73!

Tom - KB2SMS

KX2 #01927

On 11/23/2017 02:51 PM, Barry N1EU wrote:

> I'd appreciate hearing from others who are using their KX2 in FT8 mode in
> terms of your experience with power output and acceptable PA heat level.
> The reason I ask is that I'm running 5W on 40M with the rear foot down (rig
> tilted up) and I'm seeing the PA temp reach 60deg C in ordinary qso'ing
> (i.e., xmit for 12 sec out of each 30 sec period) with low SWR. How much
> power are you running? Are you using extra cooling of any type?
>
> Thanks & 73,
> Barry N1EU
>

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N1EU

Re: KX2 in FT8 mode - heat?

I think the problem only shows up if you're consistently transmitting
(i.e., 12 sec every 30 sec). My use case is doing a SOTA activation in FT8
mode and having several callers waiting to work me so I could make 5 - 10
qso's in a row without gaps. That's when the KX2 seems to really heat up.
It must be retaining heat through the 18 sec of down time before the next
transmitting cycle, and this slowly raises the baseline temperature. This
is evidently NOT a good use case for the KX2 at the 5 watt level, except
perhaps if the ambient temperature is low.

73, Barry N1EU

On Thu, Nov 23, 2017 at 9:46 PM, Tommy <[hidden email]> wrote:

> Barry,
>
> I run 10w through my KX2 with the back leg down to allow for airflow
> and don't find heat to be an issue. I'm not TXing all that much, I'm a hunt
> & pounce type with occasional CQing. In the summer I ran a small fan over
> it to help a bit. No issues for me. I normally see it get to the mid 40's
> c. 1:1 swr's.
>
> 73!
>
> Tom - KB2SMS
>
> KX2 #01927
>
>
>
> On 11/23/2017 02:51 PM, Barry N1EU wrote:
>
>> I'd appreciate hearing from others who are using their KX2 in FT8 mode in
>> terms of your experience with power output and acceptable PA heat level.
>> The reason I ask is that I'm running 5W on 40M with the rear foot down
>> (rig
>> tilted up) and I'm seeing the PA temp reach 60deg C in ordinary qso'ing
>> (i.e., xmit for 12 sec out of each 30 sec period) with low SWR. How much
>> power are you running? Are you using extra cooling of any type?
>>
>> Thanks & 73,
>> Barry N1EU
>>
>>
> ______________________________________________________________
> Elecraft mailing list
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>
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