Excalibur WR-G31DDC as Panadapter?

[KC1UA]

Hi folks,

I just picked up a Winradio Excalibur WR-G331DDC for a nice price used. I'm greatly looking forward to using it for its obviously primary job as an HF receiver.

However, taking into consideration its spectrum analysis capability, has anyone that owns one tried to use it as a panadapter/spectrum display for a receiver with a 10.7 MHz output, such as an Icom IC-R7000, R8500, AOR AR5000, etc.?

I don't see why this wouldn't work, and obviously the receiver providing the output would have to have the VFO utilized to roll to a spike when observed.

Has anyone tried this? If so was it necessary to attenuate the 10.7 MHz IF or was it fine as is?

Thanks in advance!

 

[blantonl]

You'll need to make sure you have a DC block between the IF output and the antenna input of the Excalibur. The excalibur doesn't have a DC block on the antenna input like other SDRs like the SDR-14/SDR-IQ etc.

Other than that it should work fine.

I have an Excaliber Pro and I consider it one of the best HF Receivers I've ever owned.

 

[KC1UA]

Boy I'm glad you mentioned the DC block, that was the one thing I was not taking into consideration. Thanks Lindsay!

 

[KC1UA]

On follow-up, I'm not seeing any reference or evidence that the AR5000A+3 has voltage on its IF output. I checked with a known working voltmeter and found nothing, the manual gives no indication of voltage, and a Google didn't seem to turn up anything either. I know the Icom's have DC on their IF outs. The only thing I've ever used the IF out from this AR5K is the SDR-14 so as you mention it wasn't a concern. The only reference I found to voltage coming out of the AR5K is via the accessory jacks.

 

[Token]

The Icom R-7000, R-7100, and R-8500 all have voltage on the IF, it is used to drive the TV adapter. You can either use a DC blocking cap or you can mode the Icom not to put out the DC voltage.

I have used the G31DDC and the G33DDC as a panadapter on the R-7000 and the R-8500.

Here is a shot of the 2 meter band using that setup:
http://www.pbase.com/token/image/145218212/original.jpg

And here is 450 to 465 MHz:
http://www.pbase.com/token/image/141428064/original.jpg

Both of the above images are pretty large images.

I have been playing around with RBASIC and have a very rough program sort of working to change the offset and send commands out to the R8500 to center the RX and keep the SDR and R8500 in sync. Someone who actually knew what they were doing could probably make something work well using RBASIC.

T!

 

[KC1UA]

Thanks Token,

I have a lot to learn about the G31, I gave it a quick run as a panadapter and wasn't thrilled, undoubtedly largely due to my inexperience with the overall setup. I'll continue to play with it.

In your screenshots, I guess you're using the frequency offset to display the actual frequencies, or is this the RBASIC program you were referring to.

In any event thanks for sharing the information. Primarily I use an SDR-14 with my AR5K as a panadapter, which is unbeatable, but looking forward I'm curious as to how well this setup can be made to work. I'm not "quite" in the market for a G39 yet....just short of hitting the lottery.