I'm using the AVCOM SDM-42B display with my RX-340...to use this unit
you have to have the accessory 45 MHz IF unit installed which then
interfaces with the 1st wideband mixer output at 45.455 MHz. I THINK
the low end of the chain at 455 Khz may not be wide enough to give you a
decent display width. Usually run the display with a width of about 100
KHz which lets you see lots of signals (and some birdies too
unfortunately). AVCOM has software that when connected to the SDM will
display the same info on your PC. The software was originally intended
for their spectrum analyzers so many of the measurement functions do not
operate with the SDM. I/O is thru a serial port--they used to have an
accessory adapter that interfaced via the PC's parallel printer port but
I could never get it to work until they upgraded my unit to a serial
I/O. The communication with the PC is only one-way so you couldn't
control the RX-340 with this unit even if you wanted to.

Be advised the unit is pricey (even after they significantly reduced it
a year or so ago) and support for that unit is VERY low on the company's
totem pole of products....but it sure is nice to be able to see the band.

As far as I know this is the only hardware spectrum display unit you can
use with the RX-340. The AOR units have only 10.7 MHz inputs. BTW,
with the 45 MHz converter installed you retain the use of a second
channel at 10.7 MHz for another receiver -- I've got the Icom R7100
hooked to that port so the SDM-42B supports both radios.

Dino KL0S/4

In article .com,
wrote:

Somebody Somewhere wrote:
Is there a stand-alone, or PC software-based, RF spectrum display that
can interface with the 455khz IF output of a Ten-Tec RX340? I don't
really want PC control of the RX340, just a spectrum display. Thanks.

I don't think this is likely since you would need an A/D samping around
a megahertz, which isn't stock hardware on a PC. There are SDRs that
will give you a panoramic display on your PC.