TDP and RNZI DRM off-center, 4/5 Aug 2012

This afternoon was pretty good for The Disco Palace until about 20:30 UTC when a deep and prolonged fade struck, and audio remained choppy until 20:50 UTC, wherein it finished strong.

Anyway, earlier I noticed that the right edge of the signal seemed pressed right up against the edge of the demod sent to Dream. It didn't really cause a degradation in Dream's reception, but I think it's normal to have the signal roll off contained in the signal bandwidth passed to the decode chain; it's what transition bands are for.

So I shifted the demod frequency up. Closer inspection revealed that the suppressed carrier was about 176 Hz higher than expected.

I also saw a roughly 150 Hz shift in RNZI tonight, on 17675 kHz.

But RNZI on 11675 kHz is pretty dead on. Unfortunately decode is spotty. I've had better signal strength on 25 m before.