Narrative:

We had experienced an 'altitude hold' autoplt problem earlier in the flight and were watching the autoplt closely. After cleared for ILS we tried contacting tower with no reply. Received a green light and landed. Ground said they never heard us and we could only hear them with the squelch on. At cruise we had noticed some problem receiving center, but we were able to hear other aircraft so we thought it was center's transmitter. That night when unpacking I noticed a highway toll transceiver, on, in my bag. I removed the batteries. Next day we had no problems with either radio. It is very possible we had interference from a portable electronic device. Callback conversation with reporter revealed the following information: in conversation with the reporter it was revealed that, the 'highway toll transceiver' was located in the forward bag compartment, adjacent to the avionics bay. Fortunately all interference stopped, with normal VHF operation, once the batteries were removed from the transceiver. The aircraft has been flown on subsequent flts with no reoccurrence of the problem.

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Original NASA ASRS Text

Title: AN H25A CREW, ON APCH TO PVD, UNABLE TO CONTACT THE TWR VIA VHF COMS WERE ISSUED A GREEN LIGHT CLRING THEM TO LAND.

Narrative: WE HAD EXPERIENCED AN 'ALT HOLD' AUTOPLT PROB EARLIER IN THE FLT AND WERE WATCHING THE AUTOPLT CLOSELY. AFTER CLRED FOR ILS WE TRIED CONTACTING TWR WITH NO REPLY. RECEIVED A GREEN LIGHT AND LANDED. GND SAID THEY NEVER HEARD US AND WE COULD ONLY HEAR THEM WITH THE SQUELCH ON. AT CRUISE WE HAD NOTICED SOME PROB RECEIVING CENTER, BUT WE WERE ABLE TO HEAR OTHER ACFT SO WE THOUGHT IT WAS CENTER'S TRANSMITTER. THAT NIGHT WHEN UNPACKING I NOTICED A HIGHWAY TOLL TRANSCEIVER, ON, IN MY BAG. I REMOVED THE BATTERIES. NEXT DAY WE HAD NO PROBS WITH EITHER RADIO. IT IS VERY POSSIBLE WE HAD INTERFERENCE FROM A PORTABLE ELECTRONIC DEVICE. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: IN CONVERSATION WITH THE RPTR IT WAS REVEALED THAT, THE 'HIGHWAY TOLL TRANSCEIVER' WAS LOCATED IN THE FORWARD BAG COMPARTMENT, ADJACENT TO THE AVIONICS BAY. FORTUNATELY ALL INTERFERENCE STOPPED, WITH NORMAL VHF OP, ONCE THE BATTERIES WERE REMOVED FROM THE TRANSCEIVER. THE ACFT HAS BEEN FLOWN ON SUBSEQUENT FLTS WITH NO REOCCURRENCE OF THE PROB.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.