Sunday, May 1, 2011

Fun with Pappradio - Mobile DRM

Here is a repost since my first "fun with Pappradio" got eaten somehow!

Today I loaded my Asus Eee PC 901A, Pappradio and C. Crane FM modulator into my Honda and went for a drive. Disco Palace and TDP Radio were on so I knew I'd have nice signals to work with. I must say I was pleasantly surprised.

I have a sturdy 3/8 - 24 type magnetic mount and put a 20M Hamstick on. At first, signals were just too weak for consistent copy. I decided that perhaps I needed more metal in the air and attached a 2M Hamstick (less loading and a longer steel whip). Immediately I had nice solid decode and hence Disco music. I cruised the neighborhood with my windows open blaring the music. This attracted no attention since that is how the teens around here listen to music anyway.

I noted that near some power lines I lost decode. I also noted that the signal level in DReaM was lower than I am accustomed to here at home. Even taking that into consideration, there was a fleeting moment of 29 dB SNR.

Perhaps I'll try a preamp next time. At any rate, I had a fun drive and proved once again that Pappradio and DRM are a great team, even "going mobile"! Have any of you experimented with DRM in your rig? Seems like an RVer or Trucker might have the right ground-plane and really get good solid copy if signals were right. Alas, we only have a few strong DRM broadcasts here in North America.

Late note: I forgot to mention that using the 12V Cigarette Lighter adapter to power the Asus caused too much hash. I reverted to internal battery power. Would likely have had about 3.5 hours until those batteries were depleted. What antenna would likely work best? 102 inch steel whip? Active antenna? Some kind of loop?