K3 - Temperature Specifications

[Stewart Baker]

I have had my K3 on receive most of the day, whilst doing other
things in the shack.

By chance I touched the top of the case and it felt quite hot,
given that the shack temperature is 26 deg. According to the LCD
readout both the FP and PA temps were at 34 deg.

It got me wondering,  what are the temperature specifications for
the K3 ?
I have looked through various paperwork on the Elecraft site, but
can find no information on the subject.

73
Stewart G3RXQ
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[Gary, W7TEA]

Stewart, I don't know the specifications.  My shack is 23C and the K3
has been on receive all day.  The FP is 31-32C and PA is 30C.  
My fans start when I'm barely into a QSO and when the PA reaches 37C.  
I calibrated the PA just yesterday.

73, GAry W7TEA

<quote author="Stewart Baker">
I have had my K3 on receive most of the day, whilst doing other
things in the shack.

By chance I touched the top of the case and it felt quite hot,
given that the shack temperature is 26 deg. According to the LCD
readout both the FP and PA temps were at 34 deg.

[Stewart Baker]

Thanks Gary (and others),
I think that since fitting the 2nd RX the unit gets quite a bit
warmer. The supply volts are 13.7 and the current on receive is
1.07A, so that's about 14W, not excessive.

If the unit is on receive and the fans are not running,  the only
place for the heat to escape from the front half of the K3 is via
the speaker hole, and by conduction through the case. The slots at
the back half of the top cover seem to let little heat out because
of the height of the PA shield.

Haven't got an 'official' reply yet.

73
Stewart G3RXQ
On Sun, 31 Aug 2008 21:03:37 -0700 (PDT), W7TEA wrote:
>
> Stewart, I don't know the specifications.  My shack is 23C and
the K3
> has been on receive all day.  The FP is 31-32C and PA is 30C.
> My fans start when I'm barely into a QSO and when the PA reaches
37C.

> I calibrated the PA just yesterday.
>
> 73, GAry W7TEA
>
>
> I have had my K3 on receive most of the day, whilst doing other
> things in the shack.
>
> By chance I touched the top of the case and it felt quite hot,
> given that the shack temperature is 26 deg. According to the LCD
> readout both the FP and PA temps were at 34 deg.

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[Enno, PF5X]

Hi Stewart,

I have a K3/100 + KRX3/KXV3/KAT3.

In RX/stby it runs 1.01 A @ 14V according to the K3 display. I agree that the temperature is quite high. With about 26.7 degC in the shack I read FP 41 degC and PA 36 degC after >1 hr stby. I guess the two DSPs are generating quite some heat + the FP lamps. I have the display at its lowest brightness (2).

When I make a QSO with a couple of transmissions the PA temp rises to about 41~43 degC. The fans are very efficient in cooling down the PA quickly afterwards.

Comparing the "feel" temp of the K3 case with other rigs (FT1000MP and IC736), give me the impression that all this is not excessive.

BTW. I wonder what current exactly is measured and displayed (could not find a clue in the owner's manual). 14 W in standby with AF volume at normal level, with all my options, seems a bit low. I would rather expect something in the range of 50 to 100W.

-- Enno, PF5X

Stewart Baker wrote

Thanks Gary (and others),
I think that since fitting the 2nd RX the unit gets quite a bit
warmer. The supply volts are 13.7 and the current on receive is
1.07A, so that's about 14W, not excessive.

If the unit is on receive and the fans are not running,  the only
place for the heat to escape from the front half of the K3 is via
the speaker hole, and by conduction through the case. The slots at
the back half of the top cover seem to let little heat out because
of the height of the PA shield.

Haven't got an 'official' reply yet.

73
Stewart G3RXQ
On Sun, 31 Aug 2008 21:03:37 -0700 (PDT), W7TEA wrote:
>
> Stewart, I don't know the specifications.  My shack is 23C and
the K3
> has been on receive all day.  The FP is 31-32C and PA is 30C.
> My fans start when I'm barely into a QSO and when the PA reaches
37C.
> I calibrated the PA just yesterday.
>
> 73, GAry W7TEA
>
>
> I have had my K3 on receive most of the day, whilst doing other
> things in the shack.
>
> By chance I touched the top of the case and it felt quite hot,
> given that the shack temperature is 26 deg. According to the LCD
> readout both the FP and PA temps were at 34 deg.


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[KK7P]

> ...14 W in standby with AF volume at normal
> level, with all my options, seems a bit low. I would rather expect something
> in the range of 50 to 100W.

The heritage of the K3 is portable operation, so we worked pretty hard
at keeping the current drain low without sacrificing performance.

Maybe the K3 should be eligible for a Carbon Tax Credit?

73,

Lyle KK7P


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