[Kenwood] ts940s fluttering output?
[email protected]
[email protected]
2002年7月17日 11:56:34 PDT
One of my ts940's is an early model serial number
51200XX, and it seems to be having difficulty
with fluctuating/fluttering output levels in
cw/ssb modes.
While the instruments available to me are
not too precise, according to the power out indicator
in the rig, and an external power meter, the flutter
appears to be about 5 watts or so in magnitude. The
VC remains constant but the IC fluctuates.
I had pulled the control board to change R262 to 8.2k
to fix a problem with the receive audio during qsk
operation, as per a Kenwood service note. Changing
the resistor fixed the received audio problem, but
when I went to test the rig, the above problem was
there. I cannot say for certian that the problem was
not there before I did the modification, but I had
not noticed it before. I have double checked the
connectors on that board, and resoldered some suspect
connections, but the problem persists.
One other piece of information is that the VC remains
at 29v in all bands except 28/29mhz where after a
second or two in transmit mode the voltage goes up
to 30v.
One other thing I notice is that unlike my later
940's this one gives full output when you push the
"send" button when in CW mode. Is this typical?
Were later models changed? If so, why?
I am currently in the field, and the only test equipment
I have available is a VOM, and external watt meters.
Any suggestions as to where I should be looking would
be greatly appreciated.
Thanks in advance.
cheers, Paul - VA7NT ex VE7CQK - email: [email protected]
"Those who hear not the music. . . think the dancers mad."