Don, it was a short betwen either RFC1 or RFC2 and one of the crystal
cases that caused the problem.
Really embarassing because it was basically the first and only real
problem I have come upon building my K2 #5810 and all the extras... :-)
It's so easy to happen that I really think it should be pointed out in
the manual.
73 de
Haakan / SM6EQO
--
Don Wilhelm skrev:
Haken,
At this point, do not be concerned about those voltages you found did not
agree with the chart in the manual.
The no voltages at the diodes is a cause for concern. The problem may be in
where you measured for voltage or the settings you were using. We will get
to that.
Let's verify that the source for the diode switching voltages are correct:
First thing, set the SSB FL1 filter to OP1 (using the K2 menu). Set the K2
to SSB mode and be certain FL1 is selected. Now measure the voltage at U1
pin 21 (should be about 6 volts), and measure the voltage at U1 pin 22
(should be near zero volts).
Now, switch to CW mode (any of the CW filters is OK), and measure the
voltage at U1 pin 21 (should now be near zero volts) and U1 pin 22 (should
now be near 6 volts). You should also find about 6 volts at the cathode of
D7 and D8 and at the cahode of D11 and D12. If you do not have these
voltages present, check to be certain RFC1 and RFC2 are not shorting to the
crystal cases (insert a sheet of paper between the choke and the crystal as
an insulator).
If all the checks above are correct, switch back to SSB mode, FL1 (OP1)
filter and check for about 6 volts at the cathode of D6 and D9 and at the
cathode of D10, D13 and D14.
If you find all those voltages correct, the filters should switch between
the CW filter and the SSB filter.
Just as information if you are following the schematic - the RXC signal
indicates that receive should be through the CW filter when this signal is
active (about 6 volts), and RXS indicates that the receive path is through
the SSB filter when this signal is active.
Make the checks above, and if that did not lead you to fine the source of
the problem, send us your report of your findings.
73,
Don W3FPR
-Original Message-
I have just put together the KSB2 SSB ADAPTER and I have problems.
Referring to the manual on page 15 “Initial Test” the last paragraph
“Verify that the K2 performs...” I do not get any sound in the
loudspeaker, or the sound I get is very very muted. I can hear some very
faint - both CW and SSB – signals but only when the volume is turned up
to max.
Else there is no problem doing the “BFO Test”, “Receive-Mode SSB Filter
Test” and “BFO Setup for LSB/USB”
I have checked the voltages as seen on page 23 in the manual and found
the following anomalies in receive mode:
U1-21... zero volt (should be 5.8)
U2-5 6.0 volt (should be 0.6)
U4-3 6.0 volt (should be 0.6)
D10-D13 and D6-D9... no voltage in receive mode.
So, what could be the matter?
73 de
Håkan / SM6EQO
--
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