IC-R8600's Digital Twin Passband Tuning

There is a handful of nearby AM radio stations that are very strong here and sometimes make it difficult to hear stations on adjacent frequencies, for example, WPRX on 1120 kHz running 1000 watts 2 miles away, WNTY on 990 kHz running 2500 watts 5 miles away and WLAT on 910 kHz running 5000 watts 8 miles away. But by far, the worst is WTIC on 1080 running 50,000 watts line-of-sight 16 miles away. Its 50 kilowatts are bad enough, but it also uses IBOC, which dumps hash on 1070 and 1090 that is 20 over 9.

Despite the hash, I have managed to bag seven stations on 1070 by rotating my radios and/or antennas to null WTIC's signal.

I wondered if my new whiz-bang ICOM IC-R8600 could handle WTIC's IBOC hash. Studying the IC-R8600 manual, I thought that the radio's "Digital Twin PBT" might solve the problem.

"The Digital Twin PBT (Passband Tuning) electronically narrows the IF passband width by over wrapping the passband frequency ranges of 2 PBT filters (PBT1 and PBT2), to reject interference."

So I saddled up to the radio last night around 2330 local time, powered up the IC-R8600 and found Radio Havana loud and clear on 530 kHz, so conditions were very good and WTIC's IBOC hash would be very strong. Tuning to 1070, all I could hear was the IBOC hash.

I selected the Twin PBT option and began adjusting the two PBT filters (see figure above). In less than a minute, the IBOC hash gave way to The Eagles singing "Already Gone" on CHOK in Sarnia, Ontario!

Twin PBT did the trick!

A Very Good Night

I recorded the top of the hour (1000 UTC on November 29) and was very pleased with the results.

WPRX was off the air for some reason. Their transmitter is 2 miles away and although it only transmits 1,000 watts, I cannot hear anything but WPRX on 1120 kHz. With WPRX off the air, I logged KMOX for the first time, the St. Louis powerhouse transmitting 50 kW, 923 miles to the west-southwest.

I also logged three other new stations:

WWLZ on 820 kHz in Horseheads, New York, transmitting 850 watts, 204 miles to the west-northwest.

WTAD on 930 kHz in Quincy, Illinois, transmitting 1,000 watts, 973 miles to the west.

WQWK on 1450 kHz in State College, Pennsylvania, transmitting 1,000 watts, 261 miles to the west-southwest.

All four were received with the ELAD FDM-S2/FDM-SW2 receiver and Hy-Gain 18AVT/WB-A vertical antenna.