Playing Devil's Advocate in the Disruptive Orchestra of Change!
Good luck. I've been extremely disappointed with DRM here in the eastern US. It seems that the only way to receive a signal is to have a very quiet receiving location and to then look right down the barrel of a transmitter aimed directly at you. The signal has to be strong enough that if you were listening in AM mode, the sound would be better than what you get in DRM mode. Oh, and the signal/noise ratio has to be excellent; if it's anything less, you get nothing. I'm deeply skeptical that a radio like the Mayah you'll be testing will be able to hear anything at all if it's inside the noise field generated by a typical house because of that last requirement. And since there aren't many transmitters aimed directly at us, there's essentially nothing to listen to here. You might get something on 9800 kHz between 1955 and about 2400 UTC from Sackville, and there's a transmission or two from Bonaire that I'm sure you know about, and that's it.I was very keen on DRM until I actually got a radio capable of receiving it. Now I think it's a joke.I look forward to seeing the results of your testing. I would love to be proved wrong in my belief that DRM has no future in this hemisphere.ralph
I did say in theory. Which radio are you using? I've been monitoring MW tests from Luxembourg and they work fine. But SW is going to be a different thing with all the IT interference from Silicon Valley.
I'm using an AOR AR-7030 Plus, modified by AOR UK with a 12 kHz IF output. This is the same radio that the DRM consortium was pushing last year as a testbed for DRM. It's connected to 300 feet of wire pointed directly at Europe which exhibits significant directionality toward Europe, but not so much that I only hear part of Europe. The antenna is very quiet; it doesn't even start until about 50 feet away from the house and runs through a stand of woods on our property. The first week I had the radio back from AOR UK, I was using a Dressler ARA-60 antenna mounted in my attic, and the noise it received made reception of even Sackville and Bonaire a questionable thing. That's why I think the Mayah and similar portables (if they ever arrive) will be a flop here in North America, because I have a hard time thinking of a more ideal setup than the one I have, and even I can't hear much. Try to use a DRM radio in the noise generator that is a typical American house and I suspect the S/N ratio is going to drop significantly to a point where reception is not possible.I don't doubt the situation is different in Europe, where there are so many relatively small countries with huge transmitters in close proximity to each other. I wouldn't be surprised to see DRM as relatively successful in those circumstances. But for DRM to be useful here, RNW and RCI are going to have to significantly build out their transmitter plants to meet the demand. Regular transmissions from Europe seem unlikely. The VT Digital tests a week or two ago had pretty lousy audio most nights, to the point that it wasn't until 15 minutes into the first broadcast that I realized who the announcer was. :-)I'm not one of the luddites who says "I'm not going to listen to DRM -- it's not real shortwave" who you can see on the newsfroups and mailing lists. My concerns with DRM come as a result of spending a lot of money and going to a lot of effort to set up as good a system as I could and finding it wanting. I'm completely underwhelmed by DRM, and I didn't want to be.ralph
Thank you for your interest in DRM. Given that it's inauguration only was in 1998, it's quite a speedy development. However, please keep in mind that it's not in production stage yet. That goes for RX's (chips and all) as well as for distribution, there's a lot out there already, but, understandably so, yet a long way from full blow regular volumes. Consumer (chip based, not IC based like Mayah) 1st half 2005, large volumes Xmas 2005. Watch the IFA's.Jan
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