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Messages - R4002

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121
Russian taxi cab radio chatter logs - YL dispatcher Olga Russian Taxi Controllers Russian PMR LMR land mobile radio comms VHF low band 11m band 27MHz CB band


25.615 MHz FM
25.650 MHz FM
25.665 MHz FM
25.675 MHz FM
25.705 MHz FM
25.725 MHz FM
25.765 MHz FM
25.770 MHz FM
25.775 MHz FM
25.845 MHz FM
25.875 MHz FM
25.925 MHz FM
25.945 MHz FM
25.955 MHz FM
25.965 MHz FM
25.975 MHz FM
26.000 MHz FM
26.025 MHz FM
26.045 MHz FM
26.050 MHz FM
26.060 MHz FM
26.065 MHz FM
26.085 MHz FM
26.105 MHz FM
26.115 MHz FM
26.125 MHz FM
26.145 MHz FM
26.155 MHz FM
26.175 MHz FM
26.185 MHz FM
26.195 MHz FM
26.205 MHz FM
26.260 MHz FM
26.275 MHz FM
26.285 MHz FM
26.335 MHz FM
26.365 MHz FM
26.375 MHz FM
26.485 MHz FM
26.495 MHz FM
26.505 MHz FM
26.525 MHz FM
26.560 MHz FM
26.600 MHz FM
26.605 MHz FM
26.620 MHz FM
26.625 MHz FM
26.630 MHz FM
26.645 MHz FM
26.650 MHz FM
26.670 MHz FM
26.675 MHz FM
26.680 MHz FM
26.700 MHz FM
26.725 MHz FM
26.750 MHz FM
26.760 MHz FM
26.765 MHz FM - with QRM from taxi cab dispatcher on same frequency using AM mode 26.765 MHz AM
26.770 MHz FM
26.775 MHz FM
26.780 MHz FM
26.825 MHz FM
26.855 MHz FM
26.900 MHz FM - with very heavy QRM from paging/data POCSAG on 26.9 MHz
26.950 MHz FM - with very heavy QRM from paging and data on 26.950 MHz, 26.945 MHz and 26.955 MHz
26.980 MHz FM
27.005 MHz FM
27.040 MHz FM
27.050 MHz FM
27.055 MHz FM
27.120 MHz FM
27.170 MHz FM - with heavy QRM from 27.170 MHz USB SSB chatter
27.200 MHz FM - extreme QRM from 27.200 MHz and 27.205 MHz
27.255 MHz FM - noted heavy QRM from voice and RCRS data signals on 27.255MHz
27.270 MHz FM
27.330 MHz FM
27.350 MHz FM
27.400 MHz FM - severe QRM from SSB CB signals on/near the frequency
27.410 MHz FM
27.415 MHz FM
27.420 MHz FM
27.430 MHz FM
27.440 MHz FM
27.490 MHz FM
27.500 MHz FM
27.510 MHz FM
27.540 MHz FM
27.575 MHz FM
27.580 MHz FM
27.585 MHz FM
27.625 MHz FM
27.645 MHz FM
27.650 MHz FM
27.675 MHz FM
27.705 MHz FM
27.715 MHz FM
27.720 MHz FM - heavy QRM from UK FM CB comms and SSB freeband CB signals
27.725 MHz FM
27.735 MHz FM
27.745 MHz FM
27.750 MHz FM - POCSAG pager also active on this frequency
27.755 MHz FM
27.765 MHz FM
27.775 MHz FM - causing severe QRM with UK FM CB Channel 19 - 27.78125 MHz FM
27.795 MHz FM
27.805 MHz FM
27.815 MHz FM
27.825 MHz FM
27.835 MHz FM
27.845 MHz FM - severe QRM from POCSAG paging system on 27.848 MHz
27.850 MHz FM - severe QRM from POCSAG pager signals on 27.848 MHz and UK FM CB chatter on 27.851 FM
27.855 MHz FM - with very strong QRM from freebanders on 27.855 MHz AM
27.865 MHz FM
27.875 MHz FM
27.885 MHz FM
27.895 MHz FM
27.900 MHz FM
27.905 MHz FM
27.915 MHz FM
27.925 MHz FM
27.935 MHz FM
27.945 MHz FM
27.950 MHz FM
27.955 MHz FM
27.965 MHz FM
27.975 MHz FM
27.985 MHz FM
27.995 MHz FM
28.005 MHz FM - severe QRM from 10m CW signals
28.050 MHz FM
28.055 MHz FM
28.100 MHz FM
28.105 MHz FM
28.115 MHz FM
28.125 MHz FM
28.145 MHz FM
28.155 MHz FM
28.175 MHz FM
28.195 MHz FM
28.205 MHz FM
28.210 MHz FM
28.215 MHz FM
28.225 MHz FM
28.245 MHz FM
28.260 MHz FM
28.265 MHz FM
28.275 MHz FM
28.300 MHz FM
28.305 MHz FM
28.310 MHz FM
28.315 MHz FM
28.325 MHz FM
28.335 MHz FM
28.355 MHz FM
28.375 MHz FM
28.585 MHz FM
29.745 MHz FM
29.805 MHz FM
29.815 MHz FM
29.855 MHz FM
29.885 MHz FM
29.905 MHz FM
29.915 MHz FM
29.945 MHz FM
29.955 MHz FM
29.965 MHz FM

122
Lots of Russian comms coming in this morning on the G8JNJ SDR.  Noted taxi cab land mobile radio dispatch on

27.420 MHz FM - strong YL dispatcher getting obliterated by SSB QRM




27170 kHz USB 27.170 MHz USB
27180 kHz USB 27.180 MHz USB
27190 kHz USB 27.190 MHz USB
27200 kHz USB 27.200 MHz USB - with very heavy QRM from 27.200 MHz FM, 27.205 MHz FM and 27.205 MHz FM, including a repeater on 27.205 MHz FM - CB Radio Channel 20 FM


123
27100 FM getting almost constantly keyed up.  Lots of activity on 11m, every 5 kHz.

124
Via G8JNJ SDR.


3000 kHz AM - note: significant QRM from Russian comms on 3003 kHz USB - 3002.3 kHz, 3002.5 kHz, 2999.9 kHz, 2998 kHz, 3001 kHz
3030 kHz AM or 3035 kHz AM?  3033 kHz, 3033.3 kHz, 3033.5 kHz, 3033.8 kHz, 3034.1 kHz
3060 kHz AM - 3058 kHz maybe - 3058.1 kHz, 3057 kHz, 3057.5 kHz, 3058.8 kHz, 3059.5 kHz
3120 kHz AM - stations on: 3119.5 kHz, 3118.6 kHz , 3121.6 kHz
3150 kHz AM - very busy - stations on frequency: 3149.2 kHz 3150.0 kHz, 3151.9 kHz, 3152.1 kHz, 3153.3 kHz
3170 kHz AM - 3172.0 kHz, 3169.0 kHz, 3171.1 kHz

3.000 MHz 3.003 MHz 2.999 MHz, 3.001 MHz
3.030 MHz AM w/QRM from Russian two way comms on 3003 kHz USB 3.003 MHz USB
3.170 MHz
3.

125
I've actually come across several voice (AM, FM and SSB) users of 27.7 MHz and nearby frequencies.

Yes, there is at least one Russian taxi cab company that uses 27.700 MHz FM for taxi cab dispatch.  27.70125 MHz FM is UK CB FM Channel 11.  Plus there's at a handful of different paging and data link systems operating on 27.7000 MHz too.

Finland has a 5 watt on-site pager and telemetry data link service on:

27.7 MHz
27.72 MHz
27.74 MHz
27.76 MHz
27.78 MHz
27.8 MHz
27.82 MHz
27.84 MHz
27.86 MHz
27.88 MHz
27.90 MHz
27.92 MHz
27.94 MHz

Bandwidth is limited 10 kHz. 

Other unknown-source POCSAG paging signals noted on 27.700 MHz as well as the "usual suspects" - freeband 11 meter CB radio traffic, most of it in SSB mode on 27.695 MHz USB, 27.700 MHz LSB, 27.700 MHz USB, 27.705 MHz LSB, and of course, AM voice comms and FM voice comms on on 27.705 MHz and 27.695 MHz and Irish churches - Parish radio (CADS / WPAS) on 27.605 MHz - 27.995 MHz and 27.60125 MHz - 27.99125 MHz.  Most of the 27MHz band church broadcasts seem to be on the LW channel plan (which is identical to the UK FM CB radio band plan), with 27.70125 MHz - or 27.701 MHz being widely used. 

The UW channels are just 27.605 MHz - 27.995 MHz (10 kHz spacing) so 27.705 MHz and 27.695 MHz come into play here. 

Since many of these transmitters are easily 1-2 kHz off frequency, a transmitter operating on LW11 or 27.701.25 MHz or UW11, which is 27.705 MHz. being only a kHz or so off-frequency means havoc to SSTV, of course, it goes both ways. 

That, and our friends the Asian fishing fleets are active on 27.700 MHz FM [CSQ].  27.7 MHz is 480 channel FM fishery marine radio (27.5 MHz - 39.475 MHz) Channel 009.  While most of the fishery chatter I've heard has been above 29, 30 MHz, they are active below 28.000 MHz.

126
Good signals via G8JNJ SDR at 1345 UTC on 21 December 2023.  29.855 FM 29,855 NFM Taxis, Russia LMR 29.7-30 MHz 29.7-50 MHz VHF low band but still more or less “10 meters” - that little sliver of spectrum between 29.700 MHz and 30.000 MHz

Not sure if they’re using export radios or actual land mobile radios.  Nice 15-16 kHz wide FM. Most export radios / 10m radios that cover 25.615 MHz - 30.105 MHz are in NFM only - that is, 8K00F3E to 8K50F3E to 10K0F3E emission.

YL dispatcher and OM drivers.  Dispatch signals a solid SIO 444.   Another Russian taxi service land mobile radio LMR PMR system operating in the 25-30 MHz region.

29855 FM 29.8550 MHz FM 29.855MHz Taxicab Radio Dispatch

127
Very nice decodes.  27.700 MHz has been really active lately

128
10 kHz wide MFSK signal on 27.760 MHz, active at the same time 27.940 MHz was booming in - along with numerous other signals from that general area, including taxi cab radio communications (taxi controllers - YL taxi dispatchers "Olga") on 25 MHz, 26 MHz, 27 MHz, 28 MHz and VHF low band (37 MHz, 38 MHz, 41 MHz and 42 MHz - specifically 37.225 MHz, 38.375 MHz and 38.525 MHz) - see thread here: https://www.hfunderground.com/board/index.php/topic,122839.0.html


https://www.youtube.com/watch?v=g7gYZsoxX0Q

^ Video showing the signal on 27760 kHz 27.76MHz.  5 watt power output limit. 

Other frequencies - also 5w power limit:

26.965 MHz - also CB radio channel 1
27.002 MHz offset frequency
27.0025 MHz center frequency
27.003 MHz offset frequency
27.007 MHz offset frequency
27.0075 MHz center frequency
27.008 MHz offset frequency
27.075 MHz - also CB channel 10
27.080 MHz - halfway between CB radio channel 10 and CB radio channel 11
27.100 MHz - halfway between RCRS / data frequency 27.095 MHz and CB radio channel 12 - 27.105 MHz
27.200 MHz
27.255 MHz - shared with CB radio channel 23, used for high power paging and data worldwide
27.400 MHz
27.700 MHz
27.720 MHz
27.740 MHz
27.760 MHz
27.780 MHz
27.800 MHz
27.820 MHz
27.840 MHz
27.860 MHz
27.880 MHz
27.900 MHz
27.920 MHz
27.940 MHz
27.960 MHz
27.980 MHz

129
37.2250 MHz FM
38.3750 MHz FM
38.5250 MHz FM

all active with Russian radio taxi radio dispatch comms, 85.4 Hz tone squelch.  Russian PMR / LMR low band VHF 25-50 MHz

Other similar logs

37.125 MHz FM 77.0 Hz
37.225 MHz FM 85.4 Hz
37.225 MHz FM 100.0 Hz
37.375 MHz FM 100.0 Hz
37.400 MHz FM 167.9 Hz
37.425 MHz FM 114.8 Hz
38.275 MHz FM 94.8 Hz
38.275 MHz FM 97.4 Hz
38.375 MHz FM 85.4 Hz
38.525 MHz FM 85.4 Hz
38.525 MHz FM 100.0 Hz
38.575 MHz FM 100.0 Hz
38.725 MHz FM 156.7 Hz
41.300 MHz FM 100.0 Hz
41.525 MHz FM 179.9 Hz
41.800 MHz FM 100.0 Hz
41.800 MHz FM 173.8 Hz
41.800 MHz FM 179.9 Hz
42.200 MHz FM 110.9 Hz
42.425 MHz FM 100.0 Hz
42.425 MHz FM 179.9 Hz
42.675 MHz FM 162.2 Hz

Like the 38.375 MHz, 38.525 MHz 38.575 MHz frequencies, 41.3 MHz FM and 41.8 MHz FM both fall within military allocations, but they are using various PL tones - No doubt other tones are in use too, avoiding QRM from any military comms, local or due to skip.    12.5 kHz / 25 kHz spacing.

All appear to be Russian taxi cab radio comms - taxi controllers taxi cab dispatch voice traffic VHF low band 30-50 MHz 25-54 MHz 30-88 MHz 38MHz band 41 MHz band 42MHz band

29-36 MHz
35-50 MHz
37-50 MHz
42-50 MHz
36-42 MHz
33-48 MHz 48,5 MHz 33-48.5 MHz
57.0125 MHz 57.5 MHz

130
Listening to 25-30 MHz and 30-50 MHz this morning on the G8JNJ “Flydog SDR”.  Lots of Russian LMR / PMR taxi cab comms on 26MHz, 27MHz, 28MHz and tons of out of band chatter all over the place.  Russians on 29.898 MHz USB (getting obliterated by POCSAG paging signals center on 29.900 MHz). 

37.225 MHz FM, with nice strong deviation 16 kHz bandwidth and very pronounced AC hum in the background, YL dispatcher Olga taxi controller 37,225 37.2250 MHz FM Russian Russia taxi cab radio comms VHF low.  The hum could also be a CTCSS tone in use, but it reminds me more of the 30-88 MHz military radio comms that have the tell-tale 400Hz aircraft power supply hum in the background. 

I know low band VHF radios like the Alinco DR-135LH cover 33 MHz - 48.5 MHz and 57.0125 MHz - 57.5 MHz, in regular wide FM (16K0F3E) and narrow FM (8K50F3E for the Alinco radio anyway).  12.5 kHz / 25 kHz steps, which fit this perfectly.  37225.0 kHz FM Russian taxi cab comms LMR land mobile radio VHF low band DX skip. 

Both 38.3750 MHz and 38.5750 MHz 85.4Hz PL tone are known Moscow taxi radio land mobile taxi radio dispatch frequencies, it’s possible that 37.2250 MHz is part of this same system. 

Moscow Russia Radio Taxi VHF Low Band PMR LMR Two Way Taxi Cab Radio system 30-50 MHz 37 MHz 38mhz band 85.4 Hz PL tone Moscow Oblast / Moscow Suburbs 37,225 38,375 38,575 85,4 PL tone CTCSS base mobile YL dispatcher

37.225 MHz possible additional part of this system. 

38.375 MHz 85.4 Hz CTCSS
38.525 MHz 85.4 Hz CTCSS

131
Its popped up numerous other times when the band is open to the eastern part of Europe.  Usually the 26.945 MHz and 26.960 MHz data link frequencies are alive when 27.940 MHz is coming in. 

Seems like the 27.450 MHz FM carrier also comes in around the same time.  The other POCSAG paging frequencies, including 27.300, 27.350 and 27.360 MHz, among other in-band frequencies, also seem to pop up around this time.  Other interesting ones include the 27.845 MHz / 27.850 MHz and the offset frequency 27.848 MHz or 27.8475 MHz POCSAG signals and the 27.505 MHz POCSAG bursts, with 1-2 kHz offsets +/- from that center frequency.  Like 27.940 MHz, 27.505 MHz seems to have numerous different bandwidth signals on it.  Some of them are closer to the 6-8 kHz bandwidth, others are 14-15 kHz and others are 18-20 kHz wide (!!)

132
10/11 meters / Re: 11m Band Activity 16 DEC 2023
« on: December 18, 2023, 1420 UTC »
Nice catch.  Band looks very busy

Looks like the biggest signals are on/near:

27.105 MHz
27.125 MHz
27.135 MHz
27.155 MHz - very busy
27.165 MHz
27.185 MHz - makes sense
27.195 MHz - signal noted on the RCRS frequency
27.205 MHz
27.215 MHz
27.225 MHz - big signals
27.235 MHz
27.245 MHz
27.255 MHz
27.265 MHz - another "big radio" channel - CB Channel 26
27.285 MHz - Very strong signals, just like 27265, 27285 is a "big radio" channel/frequency - CB Channel 28
27.305 MHz
27.335 MHz
27.345 MHz
27.375 MHz LSB
27.380 MHz LSB
27.385 MHz LSB
27.390 MHz LSB
27.400 MHz LSB
27.405 MHz AM
27.435 MHz or 27.445 MHz SSB (not sure if its USB or LSB)
27.455 MHz USB - Latin American calling frequency (see also: 26.555 MHz LSB)

Numerous other SSB signals up to 27.6 MHz, 27.7 MHz.

Looks like AM carriers on/near 27.745 MHz, 27.755 MHz, 27.765 MHz, plus 27.805 MHz, 27.815 MHz and again in the 27.855 MHz, 27.865 MHz, 27.875 MHz etc. ballpark.

Several of those frequencies are confirmed Mexican taxi cab radio taxi dispatch systems, including some operating on 27.785 MHz and 27.775 MHz (which makes listening for activity on UK FM CB Channel 19, frequency 27.781.25 MHz FM a bit of a challenge).



133
31.325 MHz coming in very nicely at 1020 local time (US Eastern Time) polytone data signals.  French traffic control traffic signal control link system EPAR - I've seen it referenced as EPARS as well.  Receiver location:  Richmond VA.  Pro-106 scanner with HYS 51 inch telescoping CB whip antenna HYS 51" 27MHz CB antenna.  Also can hear it with the RadioShack center-loaded scanner/ham antenna 20-006 20-006A and the Cobra HA-TA 27" telescopic CB radio whip antenna with BNC connector "HT-1" antenna, sold under many names.  It is also base-loaded and Cobra HA-TA seems to be the most common brand name and model for that particular antenna.  Just like the HYS 51" antenna, simply reducing the length ever so slightly makes the antenna resonate in the 30-35 MHz region.

Known to use the following additional frequencies:

31.4375 MHz
31.4625 MHz
31.6875 MHz
31.925 MHz
31.975 MHz

31.325 and 31.975 seem to be the most commonly heard, along with 31.6875 MHz.  They come in nicely in NFM mode, but also in USB or LSB.  31.6875MHz tunes in fine on 31.690 MHz or 31.685 MHz if you're stuck in the proverbial 5 kHz steps land. 


31.325MHz sometimes has voice comms on it, either Asian fishery radio (27.5 MHz - 39.475 MHz, 25 kHz steps, NFM with carrier squelch (CSQ) simplex only, various LMR systems, a paging system operating on 31.320 MHz (unknown location), US based two way radio systems also on 31.3200 MHz 31.32 MHz and of course military FM comms on 31.325 MHz FM 30-88 MHz. 


The EPAR system data sounds very similar to digimode ROS (it sounds very musical).  In addition to the amateur bands, ROS can be found on 27.635 MHz, 26.735 MHz, 26.740 MHz, 27.235 MHz and 27.245 MHz on the 11 meter CB radio band.  27.235 and 27.245 being CB radio channels 24 and 25 respectively.  Most of the time it’s in FM mode but USB has been noted as well, especially on 27.635MHz. 

134
30.150 MHz FM is a good one.  I've heard a lot of traffic on there during this cycle and in during previous sunspot peaks.  It's not as consistent as, say, 30.450 MHz FM, but it's close. 

Others including 30.300 MHz, 30.600 MHz, 30.650 MHz, 30.800 MHz, 31.000 MHz, 31.100 MHz, 31.150 MHz and many many others come to mind (including 31.700 MHz FM, 31.750 MHz, FM, 31.900 MHz FM.   The 30-35 MHz region is popular, regardless of other signals/activity on/near the frequency.  A good example is 30.65 MHz FM.  There's a strong land mobile system that uses 30.640 MHz FM (among many other frequencies) and often both 30.64 and 30.65 MHz are coming in at the same time. 

I don't know about Canadian allocations, but US military has exclusive (primary) allocations for

30.000 MHz - 30.550 MHz
32.000 MHz - 33.000 MHz
34.000 MHz - 35.000 MHz
36.000 MHz - 37.000 MHz
38.000 MHz - 39.000 MHz
40.000 MHz - 42.000 MHz - note, there are several US government users of this band as well, i.e. SNOTEL on 40.670 MHz
46.600 MHz - 47.000 MHz
49.600 MHz - 50.000 MHz

Of course, they have secondary assignment for the spaces in-between and the whole 30-88 MHz band, effectively.  They often use frequencies like 35.700, 31.300, 45.500, 45.300 and others that are assigned to Part 90 land mobile on a primary basis.  That also includes military use of frequencies in the 6 meter amateur band 50MHz band 50-54 MHz.  As long as they're not interfering...

Remember the PRC-77, PRC-25 and VRC-12 family of radios did have a high band and low band, low band being 30.000 MHz to 52.950 MHz and high band being 53.00 MHz to 75.950 MHz, or 30-52 MHz and 53-76 MHz on the radio's front panel. 

The nice thing about running wideband FM voice is your signal to noise ratio is better.  Also, a non-standard tone squelch means chances of QRM from land mobile (LMR) users on the same frequency or nearby frequency is significantly reduced.  25 kHz is still the standard, but, as indicated, many radios used by militaries worldwide are capable of 12.5 kHz steps, so 30.0000 MHz to 87.9875 MHz instead of 30.000 MHz to 87.975 MHz.  Voice encryption, both wideband (25-30 kHz bandwidth) and narrowband (10-15 kHz bandwidth, roughly), plus various digital modes and multiplexed voice/data links or data-only links are also found in the 30-88 MHz spectrum.   In many instances, use of a single frequency system is the standard/norm (vs. frequency hopping).  Voice encryption is possible in SC (single channel / single frequency) and FH (frequency hopping) modes.

I believe 49.900 MHz is part of a repeater system (RETRANS), I believe in North Carolina (Fort Bragg).  I know they're also on 41.850 MHz FM, 41.950 MHz FM and many others.

150.0 Hz squelch is the name of the game.  All my scanners decode it as 151.4 Hz.  The only military comms on VHF low that I've noted without the tone squelch aren't really comms per se - but the Canadian military beacon YSD for CYSD heliport / helipad on 36.600 MHz (modulated CW "Y S D" followed by a tone burst - just like a NDB beacon).  I'm confident that YSD on 36.6 MHz FM is carrier squelch.  What the military calls "noise squelch" or "old squelch".

New squelch = 150 Hz tone operated squelch. 
Old squelch = carrier operated squelch (CSQ) or "noise squelch".   

Various secure voice signals can be seen on a waterfall display when the band is open. 

135
Thursday afternoon, 11/30/2023, I was again hearing chatter on that VHF Licensed DOT Colored FREQ of 151.625MHz, over a scanner. Usually, it's the tower workers using that to communication when climbing that American Tower, 600ft TV tower, that's 1 mile North of me. However, I was hearing a +1 sec repeater tail on this, this time. A portable / mobile flat-pack repeater? Must have been, since I didn't hear that the next day. That, and I was getting ready for work Thursday afternoon. That, was different.

151.625 MHz is the RED DOT frequency, and its an itinerant frequency.  There are licensed users of this frequency with portable/temporary repeaters on their licenses.  Much like

451.800
451.8125

464.500
464.550

are mostly used for simplex comms, as are

456.800
456.8125

469.500
469.550

But temporary repeaters / portable repeaters operating on those frequencies (low side is repeater output, +5 MHz is the input) are also quite common.

With VHF, the itnerant frequencies are:

151.505
151.5125
151.625
151.640
151.700
151.760
154.5275
158.400
158.4075

With 151.625 MHz having the least restrictions on power output.  Usually the input will be 154.5275, 158.400 or 158.4075, but there's nothing stopping somebody from using, say, 151.505 or 151.5125 or 151.700 or 151.760 as an input frequency, as long as they are licensed appropriately. 

Around here, there are plenty of low power (handheld) users of 151.625 and the others, along with a handful of high power (110+ watts) licensed itinerant users.  One of the Medevac helicopter providers for this area has a backup system that uses 151.625, 152.5275 and 158.4075 (with DCS coded squelch).  I've heard their dispatch traffic over those three frequencies, when, for whatever reason, they are having difficulty with their main dispatch system on UHF.  I can't imagine the amount of QRM the aircraft have to deal with, especially on 151.625 MHz.

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