O.k. so a status update.
Hardware is as follows
Kenwood TS-940
LP-PAN for 8.83 MHz IF from
Telepost Inc. Home Page
Edirol FA-66 firewire soundcard
PIEXX RS232 controller for the TS-940
2 balanced audio lines from stereo mini to XLR
Heil foot switch...using secondary line to 'mute' on the LP-PAN for TX mute
It goes like this
IF output RCA plug on the TS-940 into a BNC plug for IF input on the LP-PAN
Two balanced audio cables from the I and Q audio outputs of the LP-PAN into the Edirol soundcard
Mute connection (RCA) to the unused secondary cable on a Heil foot switch to the LP-PAN. This mutes the IF while transmitting so I don't get feedback on my own audio signal. It can be skipped but you'll find it very annoying to hear yourself with the delay/latency in processing...it will make you tongue tied to listen to it while talking.
Software varies in combinations.
Ham Radio Deluxe for CAT control of the TS-940, controls the frequency of the VFO via the computer for this use.
PowerSDR-IF Stage, the IF-Stage variant is significant here, it's specifically modified to track the VFO of the rig with the VFO of PowerSDR and keep a constant IF offset alignment.
Alternately to PowerSDR is Winrad. Winrad won't tune the rig though, you tune the rig on your own and Winrad 'chases' the rig.
PowerSDR-IQ is yet another...it is a more advanced version adapted than the IF Stage version with better processing and far more image rejection, however....it isn't done yet for this particular use so you have to tune it up for the frequency you are on and that's it...once you tune the VFO of the rig away from that 'center' frequency, you have to line it all up again. It is due to be modified I believe so that it will have full function.
What does all of this do for you?
Well my transmit is plain old TS-940, which is to say about 2.8kHz with audio processing and about 2.6'sh with a mic right into the rig. It's great audio, but not Hi-Fi. A good compromise though for most use on SSB.
My receive...now that is what this is all about. The TS-940 has a fixed filter. You can go narrower using the slope tune function, but you can't go wider at all. So if you are listening to nice wide band signals on a quiet night, you will never get the full quality from the TS-940.
With my setup, I have infinite filter width and shift selections. I can go to 10kHz wide or wider and at whatever passband I like. I can go down to 50Hz wide if I want to. This allows me to see the signals on the screen and see where the interference is coming from and simply click and drag the edge of the filter until it disappears. I only have to apply the bare minimum filtering to get around the interference.
Now the 'panadapter' is where you see the spectrum. As I mentioned it lets you see the signal you are listening to and also any adjacent transmissions. The width of spectrum you can see is limited by the sampling rate of your sound card. My sound card gets me right around 180kHz. 192kHz really but it drops off on the ends. What this means is, if I'm centered on 3.800Mhz I can see up to 3.890 and down to 3.710.
Any transmission within the pass band of the panadapter can just be clicked on and listened to. I can leave the primary RX at 3.8 and have the rig auto tuned to TX there and open a second receiver to monitor anything else within the 180khz range with 3.8 being the center of it.
Winrad doesn't have the second receiver option unless you listen to the primary frequency for TX through the rig speaker and then use Winrad to tune into the surrounding stations. Also, with my setup....at least from what I can find, Winrad doesn't read the frequency of the rig or tune the rig when I move around inside Winrad. With the PowerSDR IF Stage, when I tune the rig, the software follows in frequency display. When I click in the software, it actually tunes the rig all lined up for TX when I hit the switch.
The software also allows me to record at a click. Now...you don't just record what you are tuned into, you record the whole spectrum that you can see at that time. So when I record, I get the entire spectrum of 180Hz at once. When I play that file back, I can actually tune it as though I'm listening to it live.
So one great example...if you are being jammed, those guys are generally just up the band talking it up and planning what they are doing and using their call signs. Simply hit record, don't say anything and when you get a chance, play it back later and tune around until you find them...callsigns and all.
You also have various display types you can toggle. You can see audio spectrum, a panadapter frequency spectrum, a waterfall and a few others depending on software. This is very useful in analyzing signals to let people know if their rig is not performing properly or to help people figure out any issues they may be having with their signal.
In addition to all that, you have incredible DSP noise reduction, noise blanker, auto notch filters...basically anything you want to do with the signal can be done and is either already done or being worked on.
A download of new software and you have a totally new radio...or in this case just a receiver.
This is all quite beta. You'll have a pretty frustrating learning curve to figure out lining up the IF offsets, audio sampling rates and buffer sizes and all the features available once you get the initial configuration done. Don't do this if you aren't into tinkering around with software and computer settings....just don't do it. If you are up for the adventure though...it is pretty amazing stuff.
The software is all free by the way...all of it.
This should also all work in linux with linrad and likely SDR-Shell, but I haven't gotten around to that just yet...just made up all my cables and got it plumbed on Saturday.
LP-PAN
LP-PAN.html
PowerSDR IF Stage
Welcome to Amateur Radio station WU2X
PowerSDR-IQ
powersdr-iq - Google Code
Winrad
Winrad.org
Linrad
Linrad home page
Edirol FA-66
EDIROL FA-66 24Bit/192kHz FireWire Audio Capture :: Overview
PIEXX interface board
TS-940 Interface Board - $89.00 : Piexx Company, Computers & Electronics