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Here in the San Francisco Bay and Sacramento regions we have started hearing a "baby monitor" type devices using GMRS 462 and 467 MHz primary repeater frequencies, in nursing home settings (given the message content). We are aware of about twenty incidents of this over the past three months, but the rate of occurrence is rising. The most recent was strong enough to interfere with a CERT/Fire Council repeater out here. These typically operate during daylight periods, and appear to be continuously keyed for up to 12-16 hours at a time, although background noise, such as televisions, could be keeping them transmitting if set for VOX. They do not have time-out timers enabled. These change channels occasionally, but usually end up on 462.625, 462.725, 467.625 and 467.725 MHz. They use a D754 or a D734 DCS code. This kind of device was explicitly mentioned in past FCC GMRS rulings as it was feared that manufacturer's might use these channels for such things. Given most repeaters here in California are on 1500-4000 ft. mountains, continuous destructive interference will occur to our repeater inputs. I tried to DF the source of one of these last week, but it was found to be in San Francisco and we ran out of time. SF is a particularly difficult place to do this due to the density, hills and other sources. Thankfully these are constantly keyed. The device I was looking for was horizontally polarized, making it about 10-20 dB weaker when received on a vertical vehicle antenna. A Yagi in horizontal worked best. My goal was not to go after the user (they don't know better), but instead get a picture of the device, determine its manufacturer and model number, and establish who is selling it. As these may be used in nursing care facilities, they will likely have to bring the device out to us to be safe. Please let us know here if you hear these as we are trying to keep a list of the channels and codes in use so we can identify the specific radio model. This is clearly in violation of §95.1733(a)(10) and §95.1763© for GMRS, and §95.587(3) for FRS. It also appears to violate §95.533.

I have been involved with GMRS for almost 30 years and have never seen such an abrupt increase in business radio use of the 462 MHz primary channels until the last two years. It has accelerated over the past year to the point where many of us can no longer communicate with more distant repeaters from my base station between 6 AM and about 8 PM, M-F due to co-channel radio traffic. Weekends are increasingly becoming a problem as well. I have also seen an increase in adjacent-channel interference from the 12.5 kHz interstitial channels on the base station, primarily because a large number of these commercial users have FRS radios improperly programmed for wideband (25 kHz) operation. I am located in the suburbs east of San Francisco/Oakland, with 2200' mountains between me and the busy bay region. I can only imagine what the bayside users are experiencing. Anyone else seeing this problem?

Related to this topic: https://forums.mygmrs.com/topic/1971-san-diegola-600-repeater-owners-ix-from-nxdn-idas-equipped-yacht/?hl=nxdn Vessel just passed by the bay area and started interfering with our 600 repeater again this morning. Yacht is now headed to the Seattle/Port Angeles area today. See this for current position: https://www.marinetr...7/vessel:LONIAN Only seems to effect 600 repeater inputs.

A week or two ago we started receiving an IDAS/NXDN beacon on our two 600 repeaters (Oakland and Sunol CA; San Francisco Bay Area) - signal was about -79 dBm into Oakland and -100 dBm into Sunol Peak on 467.600 MHz. This would occur every four seconds, for about one second. There was occasional voice traffic as well. This was trashing most of our users. No FCC ID. What a surprise..... After several days of direction-finding (and avoiding the Oakland protests/riots) we located this station on a Yacht that was in dry dock in Oakland CA. It was part of an on-board trunked or advanced-conventional IDAS/NXDN repeater system for their crew of 24; its a big yacht. Crew was Australian. IDAS RAN=31, TGID 1-148 was common. The yacht staff was cooperative and after testing with them, they agreed to disable the repeater system until the left the bay region (they found direct mode worked just fine). The system was enabled again once they left the bay region for San Diego. They indicated they would have their two-way radio company remove this channel from their repeater system when they were back at home. Repeater owners in southern California might also be affected by this signal on 467.600. Listen to your input channel (place your repeater in carrier squelch temporarily to hear this). If you are affected, let me know and I can provide their cell number to you. Or, if you have IDAS/NXDN, the contact on board is Ryan. Vessel remains in the San Diego area as of now (7/1/2020 3:33 PM). Location: https://www.marinetraffic.com/en/ais/details/ships/shipid:5662034/mmsi:319139700/imo:9800087/vessel:LONIAN