The broadcast at 9755 kHz was the only DRM station I stood any chance of consistently decoding during the work week, because it occurred in the evening when, sometimes, I wasn't at work. It used 16-QAM for the main service channel, which made for solid reception at 14 dB.
Honestly, I don't know why operators don't run with 16-QAM MSC more often. Something like Vatican Radio, which is predominantly speech, really doesn't need the added bitrate that 64-QAM offers. People with cheap antennas (that may or may not have been pilfered from an AM radio) would get way better results. And by way better, I mean any reception at all.
Sackville is closer, broadcasts with more power, and yet there were weekend afternoons where I'd just stare at the waterfall on 9800 kHz and see consistent 14 dB SNR due to propagation conditions, and thus no audio due to 64-QAM.
One of the last broadcasts I received before Santa Maria di Galiera discontinued shortwave broadcasts to North America was on 2 June 2012, 2300 UTC. I remember this one specifically because it had its spectrum flipped, i.e. the pilot tones were on the lower sideband instead of the upper sideband, mirrored about the carrier. This was before I thought it was a good idea to take screenshots of waterfalls, so you'll just have to take my word for it.
That wasn't all. Within the first ten minutes, the transmission stopped and restarted. I thought they were going to fix the inverted spectrum, but no dice. They used a 64-QAM MSC, and audio bit rate was higher as well (17.46 kbps EEP AAC+ Mono). Usually it's 14.06 kbps with 16-QAM MSC. The audio stream frequently dropped out, and most if not all the content was in Spanish. The broadcast technically went about 10 minutes past its scheduled time with the DRM equivalent of a dead carrier (DRM modulation, empty audio frames).
I only recall this much because I dug up an e-mail I sent to Radio Vaticana. They never replied. Probably didn't see a point, since this was an unusual one-time screw up.
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