Barry,
A similar problem occurs with the KAT2 because the driver for VRFDET in
the KAT2 is not a tri-state device. The KAT100 uses a tri-state driver
and should not cause the problem you state if it is working correctly.
It is possible that the U6 in the KAT100 is not operating correctly, but
before replacing it, check a few related items:
First measure the voltage on U6 pin 8 while transmitting to one of the
Transverter bands with the K60XV low power output active - the voltage
should remain at zero (this enable signal comes from the KAT100 firmware
chip and is not an indicator that U6 is faulty, but may indicate a bad
output from U1).
If the U6 pin 8 check shows no problem, then disconnect only pin 7 from
the K2 to KAT100 cable and see if the K60XV low level output is normal -
if it is, there is something wrong with the VRFDET path inside the
KAT100. Check soldering at C38, C30, C56, R9 and U6 pin 6 to be certain
there are no solder splashes and a minimum amount of solder was used.
If all that checks out, replace U6.
73,
Don W3FPR
Barry Horning wrote:
I have the K60XV installed on my K2/100 driving my 144MHz transverter. When
testing I was able to get the full range of output up to the 1.2mW level,
however as soon as the KAT100 is linked in the output power is limited to
0.2mW regardless of the setting of the power output. This sounds like the
ATU is loading the transverter output but the manual errata notes with the
kit (Rev A-4) only recognise a similar problem with the KAT2. Is there a
similar problem with the KAT100? This happens even when operating the
transverter drive into a 50 ohm load without the transverter.
To summarise: Without KAT100 9 pin connector connected full range
transverter Tx drive output; with the ATU linked in the maximum transverter
drive is 0.2mW. I cannot find anything on this list to help, is there
somebody out there with a suggestion please?
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