[Kenwood] TR-7400A low rx audio?

Tue Jul 27 23:45:50 EDT 2004

Hi all:
I am using a TR-7400A along with a MFJ-1270B as an APRS digipeater. This my
first experience with the radio and I find that the rx audio seems quite weak.
The TNC is fed from the external speaker jack and I have to run the audio gain
at the two o'clock position for the TNC to decode the incoming packets. This
is just below the point where the audio badly distorts. When listening on the
internal speaker it is obvious that even with the gain full up the windows
will not rattle and I can't see how it could be used in a mobile environment.
I suspect that when connected to the TNC it's basically feeding an open circuit
which can't be doing it any good. While I'm trying to find a service manual can
someone tell me if this is normal for this radio? Also, is rx audio available
at the four pin mic jack?
Thanks
73 de Glenn...VE4GN