Jeff,
Is this into an antenna or into a dummy load? If it is into an antenna,
'strange things can happen' in the basic K2 configuration when the
antenna is not 50 ohms pure resistive.
Work into a dummy load first to resolve the situation (or answer your
questions). The LED bargraph should be fairly accurate (but it only
goes up to 10 watts).
If your external wattmeter does not give a good indication at a 5 to 10
watt level, you may find success in measuring the RF voltage across the
dummy load with the RF probe, then calculating the power output from the
voltage (P=V^2/R if your probe reads RF volts RMS - the one provided
with the K2 does read RMS voltage). A high range external wattmeter can
be really far off when indicating lower powers - 20% of the full range
value is a common spec for wattmeter accuracy, and on a 200 watt scale,
that is 40 watts potential error!
Yes, stick with the basic K2 until you can answer the question of how
much power is actually being developed. Once you determine that, you
can chase the cause of the problem if one exists. Don't jump to
conclusions before knowing the answer to this part of the question.
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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