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Messages - R4002

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Almost every time there's a band opening and there's activity on the lower channels (almost always AM voice traffic), there's also AM voice on the A channels 26.995 27.045 27.095 27.145 27.195.   27.145 MHz and 27.195 MHz seem to be the most popular...but I have heard folks chatting on 26.995 MHz and 27.045 MHz as well.  27.095 suffers from QRM from channel 11 27.085 MHz (just like 27.195 suffers from QRM from channel 19). 

It makes sense too - hiding on one of the five A channels vs. using an out of band channel is probably better as far as antenna performance goes (presuming the CB antenna you're using is tuned for the center of the band, which, of course, is 27.185 MHz ;)).   That being said, the low channels - 26.515 MHz - 26.955 MHz - are often just as busy when the band is rolling as they say.  The frequencies above 26.6 MHz or 26.7 MHz seem to be the most popular, see the channels that are "down one band" from the popular AM DX frequencies (the obvious exception being 26.905 MHz and 26.915 MHz, both of which are very popular when the band is open).  26.955 MHz seems to be used by truckers and hobbyists alike.

27.255 MHz has had some data on it during recent band openings...although nothing strong enough to overwhelm the voice traffic on frequency.  26.995 and 27.255 are the two frequencies most commonly used by the serious (4-watt or 10-watt) data link and telemetry systems so those are the ones I'd focus on as far as finding hidden data networks within the CB band.


Heard several stations chatting on 26815 AM 26.815 MHz AM before I started the video recording.  I actually was able to speak to two of the stations (after I stopped recording) using the CRE 8900 radio in the video...and the antenna I used was less than ideal for sure.  Transmitter power output is around 8-10 watts AM carrier power, good band conditions recently on 11 meters. 



Recorded during a big band opening on 11 meters back on 06/14/20. 

What sort of signal?  FSK?

I noticed tones and music (as well as regular AM voice traffic) during one of the many recent band openings on 27145 kHz / 27.145 MHz as well as 27195 kHz / 27.195 MHz.


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

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. 


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. 

Virginia House Radio coming in very nicely this morning on 107.7 MHz FM in downtown Richmond.  Music - faded into a relay of the local NOAA Weather Radio All-Hazards station WXK65 (162.475 MHz). 

Receiver is a factory stock Toyota AM/FM car radio with factory FM whip antenna (a real 1/4 wave steel FM whip antenna).

I managed to get two videos of the activity on 107.7 MHz:

Part 1 - https://youtu.be/Y5c3H7YibM8

Part 2 - https://youtu.be/CiOycvrTz7o

Tuned in to hear "I'll Fly Away" into "City On A Hill" at 0945 local time (1345 UTC).  SIO 444 in uptown, SIO 555 sounding really nice downtown Richmond, VA this morning. 

Live (recorded) banjo music at 0751 local time - SIO 555 in downtown Richmond, VA on 107.7 MHz FM.

10/11 meters / Re: UNID 28100 FM 2300 UTC 21 Mar 2020
« on: March 22, 2020, 1446 UTC »
How far off frequency?  Like 28097 kHz or 28099.1 kHz?  I know that 28085 / 28.085 MHz is Channel 19 "up two bands" on export radios - 27.185 MHz - 27.635 MHz - 28.085 MHz + 10 kHz switch gives you 28.095 MHz. 

Export radios that cover 25-30 MHz or so (usually 25.615 MHz - 30.105 MHz, 26.065 MHz - 28.755 MHz or 25.615 MHz - 28.305 MHz) are very popular with fisheries.   

Of course, they could also be running one of the Chinese fishery 27.500 MHz - 39.500 MHz FM fishery radio system, 480 channels 27.5 MHz - 39.475 MHz.  25 watt radios, FM voice 16K0F3E/16K0G3E emissions with 25 kHz steps (27.500 MHz = channel 1, 27.525 MHz = channel 2, etc.)  So 28.100 MHz FM fits within that channel plan perfectly as far as frequency and mode.   I could see one of those radios being 500 Hz off-frequency or so without any issue since they're running regular "20 kHz FM" or "25 kHz FM" - what's used for amateur radio and VHF low band land mobile communications. 


The FT-801 radio and similar radios are not doubt sold by fisheries equipment suppliers in Portugal, Brazil, etc. 

Apparently QRM on the 10 meter band from AM/FM export radios covering 25.615-30.105 MHz and FM fishery radios covering 27.5-39.5 MHz is extremely problematic for ham operators in Asia, since when you look at those channel plans (10 kHz steps 28.005 MHz, 28.015 MHz, 28.025 MHz, 28.035 MHz, etc. AM/FM/SSB and 25 kHz steps 28.000 MHz, 28.025 MHz, 28.050 MHz, 28.075 MHz, 28.100 MHz, 28.125 MHz, 28.150 MHz, 28.175 MHz, up through 29.575 MHz, 29.600 MHz, 29.625 MHz, 29.650 MHz, 29.675 MHz, 29.700 MHz, 29.725 MHz, 29.750 MHz to 39.400 MHz, 39.425 MHz, 39.450 MHz, 39.475 MHz, etc.)



FT-801 Fisheries Dedicated Radio Dual Signaling  fishing boat mobile transceiver

*With distress call, select call, group call, all call, sea and other communications functions call etc.
*National unity networking: able to access the nation's coastal fisheries establishment of several shore station for receiving emergency aid management and undo edits sea conditions forecast.
*Ship's position information be sent automatically and display functions.
*Full band multi-channel 27.5 ~ 39.475 MHz, total 480 channels to work.
*Fishery dedicated communication channel.

Output Power: 25 W
Modulation Limit: 5 kHz
Frequency Range: 27.5 - 39.5 MHz
Channel Spacing: 25 kHz
Number of Channels: 480
Modulation Method: FM (16K0G3E)
Power Supply: DC12V or DC24V
Signal Format: 300 baud rate ASK / 1200 baud rate MSK

Appears to have 10 kHz bandwidth receiver (for FM communications 27.5 - 39.5 MHz) as well as a medium wave and shortwave broadcast receiver covering 500 kHz - 9999 kHz (receive only).  Marine antennas for the 27.5 MHz - 39.5 MHz band are available on the Chinese market. 

Fishing boat special radio FT-801 uses high-quality parts to improve transmitting and receiving performance, intuitive LCD Chinese display screen, and easy operation. According to the needs of fishermen users, this unit adds an AM radio function to facilitate listening to weather broadcasts; Setting 4 Communication channels - 4 channels on duty (channels 221, 231, 236, 238), greatly improving the data signaling connection rate; built-in GPS module to complete positioning and navigation functions.
Fishing boat special radio FT-801 is a new type of wireless telephone with high reliability, multi-function, intuitive display, simple operation and good communication effect. Frequency range: 27.5-39.5MHz Channel grid: 25KHz Number of channels: 480

It would appear that the Chinese have a pretty extensive network set up for this band, much like the Japanese and South Koreans with their 26 MHz / 27 MHz AM and SSB fishery radio systems.  Multi-channel dual watch function for channel 221, channel 231, channel 236 and channel 238, which, if straight channel numbering is used, equal 33.075 MHz, 33.275 MHz, 33.400 MHz and 33.450 MHz.

Therefore, if these guys were using FT-801 radios or similar Chinese spec gear on 28.100 MHz FM, that would equate to channel 25 on these radios. 

Virginia House Radio Richmond Virginia still coming in nicely this afternoon (1400 local time).  Richmond VA - SIO 555 to SIO 444 in Richmond City proper.

More live recorded old time country music, mention of Floyd County, VA. 
  107.7 FM.  Virginia House Radio station in Richmond, VA 107.7 MHz pirate station.

10/11 meters / Re: 11 meter private comms?
« on: March 20, 2020, 1435 UTC »
Running DV on 11m is certainly an option.   The OP 45auto opted for VHF MURS comms instead.

It would be relatively easy to make a mixed mode FM / DMR or FM / P25 digital with encryption system on the MURS frequencies. 

At 0945 local time, hearing some of that good old time music, appears to be live recordings

0950 local - “Sunday Morning Coming Down” Johnny Cash sounding great this morning

They’re back on the air!  0930 local time tune in - DJ talking about self-isolation, followed by several minutes of dead air / unmodulated carrier...now rebroadcasting the local NOAA Weather Radio station WXK65 162.475 MHz (SIO 555 in uptown Richmond at 0936 local

Virginia House Radio 107.7 MHz FM 107.7 FM Richmond VA

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