DID I SEE SOMEWHERE THAT SOME HD RECEIVERS HAVE THE CAPABILITY TO DECODE C-QUAM?

[Jay Walker]

I swear in my readings on the web I've read about certain HD receivers having the ability to decode C-QUAM or some analog version of AM Stereo. Did I make this up?

If not it would be nice to have a backup to my ancient Radio Shack Mini-Tuner C-QUAM tuner...

 

[tomservo]

Jay, I've read this countless times both on this forum and elsewhere, but no one has ever produced a list of verified C-QUAM capable HD radios that I know of.

 

[Jay Walker]

Jay, I've read this countless times both on this forum and elsewhere, but no one has ever produced a list of verified C-QUAM capable HD radios that I know of.

Thanks Zach
I'll file this under "Urban Legend" for now...

Jay Walker

 

[rbrucecarter5]

Sangean HDT-1 - yes: http://www.ham-radio.com/k6sti/hdt-1.htm
Sony XDR-F1HD - no

That's all I know for now, I am trying to verify whether or not the current Pioneer car stereos do or not. The only C-Quam station near me is too weak to use to verify. The next time I am on the other side of town I'll test it.

 

[JohnnyElectron]

Sangean HDT-1X (must have X suffix) HD tuner does for sure - even has a display icon for it.
First generation Visteon Ford HD radio had CQuam as well, but needed a fairly strong signal to kick it in.

I've heard that the original Radio Shack tabletop does too, but it is at the reduced HD frequency response, but I cannot verify that.
I've also heard that the Directed Electronics (DICE) units do, so I will try it with my CQuam transmitter and report back.

 

[briankay]

I can verify that the Visteon HD Zoom and Directed HD100 add on HD recievers can decode C-QUAM on most C-QUAM stations, but for some reason it doesn't do it on all. WLS for example, I think it depends on how much their C-QUAM pilot tone level varies in level or frequency. Certain times for weeks on end thier stereo decodes on these receivers and other times for months on end not at all. At other locations, Peoria, IL for example, C-Quam decoding is consistent. Efforts to have the WLS engineering to give me the reason proved unsuccessful.

 

[JohnnyElectron]

Very interesting; that is probably why I can't get the Directed Electronics to consistantly decode CFCO in stereo.
CFCO originally had a slight distortion in the left channel thru their directional array at my location, but after talking to them, they backed the CQUAM pilot tone back down from the factory preset level on their Nautel, and it eliminated the left channel balance/distortion issue, but it also made it harder for radios to detect, and subsequently decode, the stereo 80 miles from the transmitter.
I'll have to get a passport to try it "locally" though...
I'll try it on WLS tonight (or better yet, 'critical hours' seems to be their best signal 200 miles out).

 

[Darth_vader]

Re: DID I SEE SOMEWHERE THAT SOME RECEIVERS HAVE THE ABILITY TO DEMODULATE C-QUA

The older Rat $hack "Optimus" tabletop Ibiquity rig (the $200 one they came out with ~6-7 years ago) could. There were actually two different versions of that model that I know of, one with the CQAM demodulator (it's NOT a decoder, people!) function enabled and one without. I don't know for certain how to tell other than by listening to it, since they used the same chassis and internal electronics, but I'm pretty sure one could discern the two by looking at the date code stickers.

 

[satech]

Best Buy's "Insignia" house brand had a tabletop stereo system and car radio with HD Radio, both of which are able to decode C-Quam AM Stereo. However, Insignia's standalone HD Radio tuner (visually similar to the Sangean HDT-1/1X) apparently does not.

I can also confirm that the Roadmaster VR3 add-on HD Radio car tuner does decode C-Quam, although its AM audio cuts off sharply above 4.5 kHz, so it is not nearly as "hi-fi" as a real analog C-Quam tuner, like the aforementioned Realistic TM-152.