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Author Topic: 49 MHz Room Monitor / Open Mic With Some Serious Range 49.830 MHz  (Read 167 times)

Offline R4002

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49.83 MHz, pretty wide signal (sounded good on 49.825 MHz and 49.835 MHz in addition to 49.830 MHz).  I was using a VHF high band 1/4 wave antenna, which is certainly not the best antenna.  Noted at least part of the signal on 49.840 MHz too. 

https://youtu.be/sJizl4V45sA

It sounds like somebody has a room monitor just on, you can hear a TV or radio in the background...at 0:59 or 1:00 in you can hear somebody say "oh you ready?".  More chatter around 1:30 and 1:40.  Interestingly enough, my scanner actually decoded too different CTCSS tones - 192.8 Hz and 196.6 Hz, on frequency. 
U.S. East Coast, various HF/VHF/UHF radios/scanners/receivers

Offline sat_dxer

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Will never understand why people get indignant about eavesdropping on 46 MHz cordless (or governments on cellular phones for that matter), but feel right at home about leaving a baby monitor bug on 24/7.
Most times & frequencies posted are only an approximation.
Due to adulteration of the E.N.I.G.M.A. "designators" they're never posted nor ever used.
-30-

Offline R4002

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This seems to be a baby monitor used for an old folks' home or to monitor an invalid neighbor or elderly family member.  I did some more listening today with a better antenna.  Previously I was using a 1/4 wave VHF antenna tuned for the 140-160 MHz region, today I used a ProComm JBC1500 60" base-loaded CB antenna tuned for just below CB channel 1, 26.6 MHz or 26.7 MHz or so, as a 1/4 wave.  That makes almost a half wave at 49 MHz....and what a difference that made.  I could hear the 49.830 MHz signal nearly full scale for 1500+ feet in all directions, extending out to 3000 feet or so before the signal completely dropped off. 

I also was able to listen to it on a purpose-built 49 MHz FM walkie talkie - specifically a Maxon PC-50 (same thing as a RadioShack / Realistic TRC-512) 5-channel 49MHz handheld, with 49.83 MHz as Channel A.   I got took two more videos:

49.830 MHz FM range testing part 1 - https://youtu.be/BOfuappHakw

49.830 MHz FM range testing part 2 - https://youtu.be/KYPXazfNeMk
U.S. East Coast, various HF/VHF/UHF radios/scanners/receivers