ICOM IC-738 HF base Rig:
Medium old HF radio, with rather nice performance. New in 1996. The unexspected clean TX audio made me try to use it for ESSB. I bought an Inrad 2.8KHz filter (#123) for the 9MHz IF and replaced the original 2.4KHz filter. This gave me much better audio quality on RX and TX. I feed the TX audio into the ACC input in the backside of the rig.
Since the RX is a bit wide for crowdy HF SSB operations, I adjust the PBT and combine this with an external DSP unit from JPS (NIR-12) and this works very well. (Maybe I find a way to switch in the narrow filter again later.)
The original filter (FL-65 2.3Khz) is now replaced with the 455KHz filter with a FL-96 (2.8Khz). The filter is put in the socket for optional CW-filter, and I had to rewire the PCB to do this. The receiver has now even better sound, and the selectivity is incredible good. The PBT function is very sharp and gives very good selectivity adjustment. Picture will come...