Jeff,
That is normal behavior - the power will climb a bit if left in TUNE for
a period of time. It is mostly the result of heating in the PA
transistors. In normal operation, either with CW or SSB, there is not a
constant carrier being transmitted and the same conditions will not be
present.
Do not leave the K2 in TUNE at high power for any significant length of
time - remember that TUNE is transmitting at a 100% duty cycle. OK for
short bursts, but not good for longer periods. The base K2 shoud be
limited to 5 watts or less for a 100% duty cycle transmission and to 35
watts or less with the KPA100.
73,
Don W3FPR
Jeff Kinzli N6GQ wrote:
Hi Don,
Thanks for the replies.
To answer your questions, the problem occurs into a dummy load.
I set the base K2 (without KPA100 connected) to 5.0W, and then TUNE,
and it starts at 5.0W and heads upwards to 5.7-6.0W (read from the
display, as well as the S-meter). After about 10 seconds in TUNE, it's
up to 5.7 or 6W and the next LED on the S-meter is starting to flicker
some.
Moving the power knob will allow me to bring it back to 5.0W, but the
next TUNE will see the power climb back up again.
I'm not sure if I should still be looking on the RF board at this
point, or start focusing on the control board...?
Thanks, 73,
Jeff
On 4/22/07, Don Wilhelm <[EMAIL PROTECTED]> wrote:
Jeff,
Another thought and a question - does the K2 control power properly
(check with TUNE) when the requested power is set to 5 watts? If you
get somewhere between 4.5 and 5.5 watts output with the requested power
set to 5, then the power control circuits are working as they should be.
Setting the power to maximum will not readily reveal any problems with
the power control.
OTOH, if the power output is always high then you do have a problem in
the power control (ALC) loop.
73,
Don W3FPR
Jeff Kinzli N6GQ wrote:
> Don and others,
>
> A few weeks back, a user posted about an issue with low power output
> with his K2. Don said:
>
>> If you do not have either the KAT2, the KPA100, or the KAT100
>> installed, the
>> K2 does not display the actual power output on the LCD (the requested
>> power
>> is displayed briefly when the power control is changed). What is the
>> indication on the LED bargraph during transmit?
>
> I'm going through an issue with my K2 where it *appears* to be putting
> out too much power. With the KPA100 installed, the output sometimes
> jumps up to 150+W.
>
> I removed the KPA100 from the picture and have been seeing if I can
> reproduce higher than normal output with just the base K2. So far, the
> behavior is that if I enter TUNE mode, the indicated power on the
> display of the K2 will rise to 16-17W. My watt meter isn't accurate
> enough to tell me what it's *really* putting out though, although with
> the KPA100 it is accurate enough to see the 150W+ peaks.
>
> So I was trying to think if it's really putting out 16+W, or if the
> power meter is really telling me it's TRYING to put it out (because my
> external wattmeter looks like actually less, but again not accurate).
>
> I also thought maybe it's an ALC issue, because if I rotate the power
> knob back then back up to max, the indicated power on the K2 will go
> to about 15W, but the next time I do TUNE again, it again goes back up
> to 16+W.
>
> Any thoughts on this? Should I keep chasing ALC issues? I've already
> gone through the base K2 RF board resoldering T1-T4, reheating
> anything that looks suspect, etc. to no avail.
>
> I also sent something to this effect to [EMAIL PROTECTED], I'm just hoping
> someone might have any ideas that I could chase down.
>
> Thanks,
>
> Jeff
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