noting IBOC QRM for 1st time on FM

[dxer2_2000]

Hi

Although I'm in Australia & we don't use IBOC, I can see how it jams 1st adjacent FM frequencies.

This I can witness 1st hand via the Montreal node on globaltuners.

I noticed that WVPS 107.9 (near local signal strength in Montreal) is running IBOC. 107.7 sounds like an empty frequency - yet the 3 signal bars are lit on his XDR-F1HD's display (can see this via a webcam showing the tuner's display).

- so this overlap would go almost unnoticed if your tuner didn't have some sort of signal strength meter showing this strong adj signal.

All I can say is....UGH!

dxer2_2000

 

[SUPERCASTER]

You can hear the loud digital hash on FM analog radios with linear tuning, or radios with smaller then full channel tuning steps. HD radio sounds similar to "white noise" or dial up computer modem hiss. Even at a level of only 1% HD's multiple digital carriers sound much louder then the stations analog signal. The HD radio adjacent channel jamming will "rock your soul" and "shake your booties". Already a speaker re-coner's delight, the proposed HD radio power increase will make the adjacent channel noise much worse, with little coverage benefit.

In the most populated areas of the US the FM dial is packed to the hilt and there are many "short spaced" first adjacent channel FM stations. The result is 2 or more signals fighting it out for the same bandwidth.