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Messages - R4002

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1
Utility / Re: CIS Navy on HF
« on: February 17, 2020, 2206 UTC »
Do the Rooskies make a habit of using 80 meters in USB mode?  Seems like it’s pretty common for marine purposes (military and otherwise). 

I’ve read numerous reports from hams in Europe of Irish fishing fleets, Finnish trawlers, Italian fishermen in the Med, etc. using 3500-4000 kHz in USB mode for ship to ship comms.  It’s a good place to hide a military net.  Same with 40 meters.

The split frequency operation seems pretty common too. 

2
Like standing on top of a several hundred (or thousand) foot tower with a HT.  Love it. 

It would be cool to go up in a balloon with a handheld CB with a halfway decent antenna. 

I’ve done some basic range testing on 2 meters and the 151 MHz / 154 MHz MURS frequencies (they have the same propagation characteristics) with another op in his mobile...I parked on top of a hill roughly 200 feet above the floodplain and low-laying area and alternated between 10 watts, 25 watts and 70 watts on with my mobile radio and 4 watts on my handheld.  Only when you get to the fringe of the 4 watt/10 watt range does having the high power capability make the difference.

Would love to do a side-by-side with 11 meter AM and VHF high band (2m or MURS) with the same power level range test. 

Of course these have been done in mostly urban areas with lots of obstructions...

In most areas, rural and urban, the proliferation of data link and telemetry systems on the MURS channels make fringe-range operation more annoying.

3
For Sale / Wanted / Barter / Re: Galaxy 959 blue
« on: February 17, 2020, 2146 UTC »
Which frequency / channel expansion mod does it have?  Does it do 26.695 MHz to 27.965 MHz coverage aka the P5 P6 or switch mod or the 26.515 to 26.955 MHz / 26.965 MHz to 27.405 MHz / 27.415 MHz to 27.855 MHz Lescomm or Viagra 120 channel board installed?

4
10/11 meters / Re: Quite a bit of activity 16 Feb 2020
« on: February 17, 2020, 2143 UTC »
Any out of band activity? On say, 26.915 MHz or any of the other freeband 27 MHz SSB freqs?

5
They’re probably getting some pretty insane range if they’re 400-500-600 feet above ground level. 

Assuming they’re using 4-watt or 5-watt handheld radios...it wouldn’t surprise me if their signals are making it 40-50+ miles from that high up (depending on the terrain of course).

I know there's a low power (~4 watts transmitter power, ERP is probably about 8 watts) simplex repeater installed in the downtown area of the city I live in...it's on MURS channel 2 - 151.880 MHz - and the antenna is maybe 30 feet above street level.   Even with that modest height and power level, it can be heard 5 miles away....and this is in an urban area with lots of obstructions.

I've monitored what sounded like either RF engineers or IT installation guys installing antennas of some sort in a high-rise building, they were talking about coax cable runs, antennas, filters and the like.  They weren't on VHF, they were on one of the UHF itinerant business band frequencies (specifically 469.500 MHz).  From their conversation it was obvious that they were either on the roof of the building or on the top floors.  They were very strong for several miles away from the downtown area, even with QRM from other business users on the same frequency.  Lucky for them they were running a DCS / DPL code and weren’t suffering any sort of QRM.

Height is key.  It wouldn't surprise me if the tower climbers on 151.625 MHz you're talking about cause at least minor amounts of QRM to all sorts of users dozens of miles away from them. 

6
Just another update: 

Heard some more very strong DMR traffic on 151.625 this morning, along with some weak analog FM voice.  023 DCS code along with 67.0 Hz, 94.8 Hz, 97.4 Hz and 136.5 Hz CTCSS tones have been logged in the past.  I know the film school for the local university uses 151.625 and 151.955 for camera crew comms and other purposes.  I've logged them as using both 67.0 and 94.8 PL tones.  Unfortunately there's also a local funeral home that uses 151.625 with 97.4 Hz PL tone, and of course Crane Master doing 110 watts with 167.9 Hz PL.

I found the listing for the default factory frequencies for the Motorola RDX series RDV5100 VHF radio:

Channel 1 - 151.6250 MHz - 67.0 Hz PL
Channel 2 - 151.6250 MHz - 77.0 Hz PL
Channel 3 - 151.6250 MHz - 88.5 Hz PL
Channel 4 - 151.6250 MHz - 179.9 Hz PL
Channel 5 - 151.6250 MHz - CSQ - carrier squelch (no PL or DPL)
Channel 6 - 151.9550 MHz - 67.0 Hz PL
Channel 7 - 151.9550 MHz - 82.5 Hz PL
Channel 8 - 162.4000 MHz - CSQ - RECEIVE ONLY - "WC" (Weather Channel)
Channel 9 - 151.9550 MHz - 179.9 Hz PL
Channel 10 - 151.9550 MHz - CSQ - carrier squelch (no PL or DPL)




Here are the "27 business exclusive" frequencies available for the Motorola RDX and RDV VHF radios (and others, including the Kenwood TK-2400 series radios such as the TK-2400VP)

Frequency 01: 151.6250 MHz - itinerant
Frequency 02: 151.9550 MHz
Frequency 03: 152.8850 MHz
Frequency 04: 152.9150 MHz
Frequency 05: 151.7000 MHz - itinerant
Frequency 06: 151.7600 MHz - itinerant
Frequency 07: 152.9450 MHz
Frequency 08: 151.8350 MHz
Frequency 09: 151.8050 MHz
Frequency 10: 151.5125 MHz - itinerant
Frequency 11: 151.6550 MHz
Frequency 12: 151.6850 MHz
Frequency 13: 151.7150 MHz
Frequency 14: 151.7450 MHz
Frequency 15: 151.7750 MHz
Frequency 16: 151.8650 MHz
Frequency 17: 151.8950 MHz
Frequency 18: 151.9250 MHz
Frequency 19: 152.9000 MHz (incorrectly printed in some Motorola manuals as "152.7000 MHz")
Frequency 20: 154.4900 MHz
Frequency 21: 154.5150 MHz
Frequency 22: 154.5275 MHz - itinerant
Frequency 23: 154.5400 MHz
Frequency 24: 153.0050 MHz
Frequency 25: 154.5475 MHz
Frequency 26: 158.4000 MHz - itinerant
Frequency 27: 158.4075 MHz - itinerant


The Motorola RMM2050 (MURS radio - license free, but sold as an on-site business radio)

Defaults to:

Channel 1 - 154.5700 MHz - 67.0 Hz PL
Channel 2 - 154.6000 MHz - 67.0 Hz PL
Channel 3 - 151.8200 MHz - 67.0 Hz PL
Channel 4 - 151.8800 MHz - 67.0 Hz PL
Channel 5 - 151.9400 MHz - 67.0 Hz PL

Motorola also identifies frequency 1 as 154.570 MHz, frequency 2 as 154.600 MHz, frequency 3 as 151.820 MHz, frequency 4 as 151.880 MHz and frequency 5 as 151.940 MHz.

7
For sale is a lightly used CRE 8900 all-mode export radio.  This is a DIN-sized version of the AnyTone AT-5555 series (also known as the SS6900/Superstar 6900, Alpha 10 Max MA-1000, Maas DX5000, K-Po DX5000, Voyage BR-9000 and a dozen other models).  See below for the specifications:

http://cbradio.nl/cre/cre_8900.htm

The radio is in excellent condition and comes with original box, mounting brackets/hardware and microphone (with UP/DOWN and automatic squelch on/off on the mic).  All-mode AM FM LSB USB CW and PA modes.  Power output is adjustable for all modes.

25 watts SSB PEP
10-12 watts AM carrier
10-12 watts FM power
10-12 watts CW power

Features:

-Selectable clarifier steps 10 Hz, 100 Hz, 1 kHz or 10 kHz (change steps by simply pushing the clarifier knob in, very useful for SSB operation)
-10 meter mode (28.000 MHz - 29.700 MHz) and 11 meter mode (25.615-30.105 MHz)
-6 band radio with 60 channels per band, fully programmable channels
-Fully adjustable RF output power for all modes including SSB
-Adjustable RF gain
-Built-in echo control (echo level and time delay control)
-Five different display color modes
-Programmable emergency channel
-Dual watch
-Noise blanker and automatic noise limiter on/off (NB/ANL)
-AF noise filter (hi-cut)
-Fully adjustable roger beep duration and tone
- +10 kHz button
-Programmable scanning with scan list
-7 digit frequency display - shows the UK FM frequencies correctly (i.e. 27.78125 instead of 27.781 or 27.7812)
-Automatic SWR indication (shows SWR on transmit) option
-Power supply voltage indication (shows DC voltage on transmit) option

Right now the radio is programmed with the standard 6 band export channel plan with some extras, including the UK FM 27/81 channels as channels 21-60 on band F) the A channels for each band, several SSB freeband channels such as 27.440 MHz, 27.470 MHz, 27.500 MHz, etc. and several 10m FM frequencies

Computer programmable (computer programming is NOT required).  I have received numerous excellent signal reports on AM, FM and SSB mode.  Several ops commented that it sounded like I was talking on a "real" HF SSB ham rig.  The very fine tuning (10 Hz and 100 Hz steps) come in extremely handy when working SSB

This radio looks great in modern vehicles and can be dash-mounted with a DIN adapter.  Will be shipped with its original box/packaging and manual/documentation.  This radio is one of the first CRE 8900s to hit the market - I actually purchased it from a UK based radio distributor before the radio was even available in the USA. 

It's been sitting in my radio closet for a while now...unused.  I recently saw a new opened box version of this radio on sale on eBay for $300.  I'm asking $250 including shipping within the lower 48.  Send me a PM.

Thanks!


8
10/11 meters / Re: Man without a life....
« on: February 14, 2020, 1333 UTC »
Josh is right, 45auto. 

If the operator in question is throwing harmonics and/or spurs on other bands, it will gain the attention of the feds quicker.  The 4th harmonics of the CB band runs from 107.86 MHz (107.9 MHz effectively) to 109.62 MHz (109.6 MHz or 109.65 MHz effectively, the VOR band uses 50 kHz steps from 108.000 MHz to 117.950 MHz).  27.025 MHz (CB channel 6) drops its 4th harmonic right on 108.1 MHz, 5th harmonic on 135.125 MHz, 6th on 162.150 MHz...

The 4th harmonics can cause serious interference with the aircraft navigation service (VOR) in the 108.0 MHz - 117.95 MHz range.  The 5th harmonics can cause serious interference with aircraft communications in the 118.000 MHz - 136.975 MHz range, specifically 134.8 MHz - 137.025 MHz.   Since CB radio uses AM mode and the VHF aircraft band uses AM mode...the source of the interference will likely get noticed pretty quickly.  If he's running that dirty of a setup he's probably causing interference all over the bands.  Aircraft communications are considered "safety of life" communications and the FCC and FAA will get involved. 

All it takes is a few milliwatts (or even microwatts, depending on the antenna used and how close the transmitter is to air traffic) to cause issues with the VHF air band.   

Prior to the digital TV conversion, the obvious issue as far as CB harmonics go is that the 2nd harmonic of 27 MHz is right on TV channel 2 (54 MHz - 60 MHz) and AM signals cause massive interference to analog TV signals.  z

That aside, a strong AM CB signal can also get into all sorts of electronics (stereo systems, computer speakers, headphones, guitar amplifiers, PA systems, VCRs, entertainment systems, etc. etc.)  it's not uncommon for a strong AM CB signal to be heard coming out of a speaker (after all, all you need is a diode to act as a detector if the signal is strong enough). 

I did a series of tests a few years back with a home built 11 meter beacon transmitter.  It did in the 50-100 milliwatt range and was connected to a dipole antenna mounted in an attic.  It was a simple AM transmitter modulated with a 1000 Hz tone generator.  Crystal controlled on 27.500 MHz (for initial testing anyway, I eventually played with other frequencies - once I got my hands on a bunch of 26 MHz - 27 MHz crystals) it made a nice carrier signal with two tones 1 kHz up and 1 kHz down from center frequency 27.501 MHz and 27.499 MHz = perfect for doing range testing with a mobile radio in SSB mode. 

Anyway, the transmitter's 1 kHz tone could easily be heard coming out of the neighbor's hi-fi system's speakers and my roommate's computer's speakers.  Sooo...that got noticed pretty quick.  The installation of a low pass filter on the transmitter and several RF chokes on the speaker wire solved the problem. 

9
Other / Re: UNID 8000 LSB 2229 UTC 2017-03-18
« on: February 14, 2020, 1323 UTC »
8888.8 kHz and 8888.88 kHz are both super easy to remember frequencies.   Same with 6666.6 kHz (which is heavily used by peskies and freebanders in the Americas). 

Interesting to know that the South Africans are using 8888.88 kHz and 12352 kHz.  It wouldn't surprise me if they used 12345.6 kHz or 5678.9 kHz, etc. 

10
Yep.  151.625, 151.955 and several others are included as the default out of the box channels for Motorola and Kenwood land mobile gear.  They’re basically the VHF versions of 464.500, 464.550, 467.925, 467.875, 467.850, 469.500, 469.550, etc.

DMR is affordable and encrypted DMR is relatively easy to implement.  Lots of users (construction companies included) seem to simply buy a massive lot of radios and use them on the factory default channels.  I know that local radio shops will often leave the radios on the factory default channels but change the CTCSS or DCS tone/code. 

For the end user, that turns into a “private channel”.  Same thing with DMR.

Crane Master - who is actually licensed for 151.625 among others, make extensive use of that frequency (with a PL tone, 167.9 Hz to be exact) for truck to truck chatter.  They’re licensed for 110 watts on 151.625 but only 45 watts on the other VHF frequencies on their license.  From what I’ve heard of them using 151.625, they are running 110 watts...

I’ve seen licenses authorized for a lot more than 100/110 watts on 151.625 and others.  I believe the American Red Cross is licensed for 110 watts PEP -on 151.625 and several other channels - base stations, mobiles and portable/temporary repeaters.  Similar licenses for temporary / itinerant systems exist with similar power levels....or even more than 110w.  Highest I’ve seen is 300w. 

The ARC is also authorized 125w PEP (500w ERP) on 27.490 MHz as part of the same license - WQMD985

https://wireless2.fcc.gov/UlsApp/UlsSearch/licenseFreqSum.jsp?licKey=3214188


Here’s another interesting one. 

https://wireless2.fcc.gov/UlsApp/UlsSearch/licenseFreqSum.jsp?licKey=4215560


11
During ducting events the NOAA weather radio channels can get pretty crazy.  I’ve logged stations hundreds of miles away during very good band conditions. 

They’re de facto VHF beacons.  The only issue is the transmitters don’t all transmit the same output power, have the same antenna directionality or elevation...but all the info (including coverage maps, transmitter output power, etc.) can be found on the NOAA Weather Radio homepage. 

12
10/11 meters / Re: 11 meter private comms?
« on: February 13, 2020, 2150 UTC »
Exactly.  There’s a couple of these data link networks that send a packet every 2-3 seconds and it can get extremely annoying...it’s usually just strong enough of a signal to open the squelch (when listening to CSQ or carrier squelch mode of course). 

With 2 watts some of these systems actually get some impressive range.  Their antennas must be quite elevated. I’m in an urban area - the presumption is the more consistent data bursts on coming from a system with at least one antenna on top of a building somewhere.

13
10/11 meters / Re: 27.555
« on: February 13, 2020, 2145 UTC »
Ahhh yes.  Reminds me of “Radio Blue Waffle” and “Number 3 Repeater” on 27.385 LSB and 27.555 USB just yakking away for hours.

Oh, and then there’s this guy:

https://youtu.be/h0HxYBGvD9g

Apparently he got The Knock eventually....

14
Peskies / Re: New England Fishermen 6263.5 USB 2005 UTC 12 Feb 2020
« on: February 13, 2020, 1446 UTC »
The Maine Based Bahstads Strike Again? 

15
Utility / Re: English EU network 6301 USB 2238 UTC 10 Feb 2020
« on: February 13, 2020, 1445 UTC »
...
I don't know if these were theirs or strangers ride on the channel + / _ 2kHz carrier.
...

What do you mean exactly?  Carriers were popping up +/- 2 kHz from the 6301 kHz center frequency?  That would make sense if they're tuning up transmitters, tuning antennas, etc. 

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