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Author Topic: 11 meter private comms?  (Read 1698 times)

Offline Stretchyman

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Re: 11 meter private comms?
« Reply #15 on: February 08, 2020, 2118 UTC »
PRIVATE & 11m don't quite go together....

Not does any standard frequency, particularly if analogue.

So any Digi mode, the more unpopular the better and a wierd non standard frequency.

I'd have a look for some basic encryption handsets but I've no idea what's available in the US but due to the somewhat paranoid nature of your government I guess not much?

Sorry I can't really recommend something decent but best avoid 11m, obviously...

Str.
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Offline R4002

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Re: 11 meter private comms?
« Reply #16 on: February 11, 2020, 1320 UTC »
PRIVATE & 11m don't quite go together....

Not does any standard frequency, particularly if analogue.

So any Digi mode, the more unpopular the better and a wierd non standard frequency.

I'd have a look for some basic encryption handsets but I've no idea what's available in the US but due to the somewhat paranoid nature of your government I guess not much?

Sorry I can't really recommend something decent but best avoid 11m, obviously...

Str.

There are actually quite a lot of encrypted radios available on the market in the US.  You can even find old Motorola SECURENET handhelds (of course, finding a KVL or keyloader is a little harder, but it is possible...).  Encrypted Project 25 / P25/P-25/APCO-25 digital voice radios and encrypted DMR digital voice radios are widely available.  Encrypted DMR is easier to use and has a lower price point.  The secondhand market is quite large in the USA.  There is a wide variation in the type of gear, bands available, etc.  VHF low 25-50 MHz (and various "splits" within the VHF low band - for example, 29-37 MHz, 36-42 MHz, 42-50 MHz, 37-50 MHz, etc.), VHF high band (136-174 MHz or 144-174 MHz), UHF band (generally 400-450 MHz, 403-450 MHz, 380-430 MHz, 380-450 MHz or 450-512 MHz) and the 700/800 band (700 - 870 MHz) are easily found.  900 MHz equipment is also out there (generally the 896-901 MHz / 935-940 MHz land mobile radio band, but this gear will usually cover the 902-928 MHz ISM/33cm ham band easily).

DMR radios with encryption capability are generally going to cover the VHF high band and/or the UHF band.  Project 25 radios with encryption capability are available for the VHF/UHF bands and 700/800 band.  VHF low band gear is available with voice inversion at the very least.  Digital voice on low band is certainly possible

No frequency is completely private.  If the OP lives in a rural area and is smart about how he uses his radios, the likelihood of interception is low, but is always there. 
« Last Edit: February 11, 2020, 1327 UTC by R4002 »
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Offline 45auto

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Re: 11 meter private comms?
« Reply #17 on: February 11, 2020, 1436 UTC »
  Again, I wish to say Thank you to R4002.

     Great info-Print-saved accomplished!

      Due to budget $$ and practicality, we opted for the VHF high band.   
      This will allow us to monitor our local NOAA, Fire, EMS and local 2 meter Ham repeaters.
     Using MURS, and Itinerary frequencies with voice inversion for private comms.     
      The TYT TH-9000D offers 50 watts for $125 each.

       -- - -
       We are also investing in an 11 meter freeband base station (SSB) for prepper comms.
       - - - -
        The great EMP or cellular hack will occur, just a matter of time, so we are storing lots of rigs within large tin boxes, Ha Ha!

            45auto in Upstate NY. 

Offline R4002

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Re: 11 meter private comms?
« Reply #18 on: February 11, 2020, 2218 UTC »
The TH-9000D is the same VHF rig I have in my car.  MURS is great.  The TH-9000D also offers voice inversion scrambling.  Program the MURS frequencies in with scrambling and then without scrambling. 

Also, since you're planning on using MURS, I would program the five MURS frequencies in with a CTCSS (PL) or DCS (DPL) tone for transmit and receive.  There are data link or telemetry systems that use the MURS frequencies and will cause an annoying "crunch" sound every time they send a data burst...and that can get very annoying.  Using CTCSS or DCS will eliminate the interference from those telemetry systems.  Remember to program the MURS channels (and everything else - except the NOAA weather channels) in 12K bandwidth mode. Program the NOAA channels in 20K bandwidth mode or 25K bandwidth mode. 

I recommend using CTCSS that isn't the default 67.0 Hz, 74.4 Hz, 77.0 Hz, 88.5 Hz, 100.0 Hz or 136.5 Hz tones.  Don't use DCS 023 either as that appear to be default ones.  Wal-Mart tends to use 67.0 Hz, 74.4 Hz, 77.0 Hz and 136.5 Hz CTCSS tones.  Other CTCSS and DCS tones/codes to avoid using include 85.4 Hz, 79.7 Hz, DCS 074, DCS 174, DCS 743 and DCS 754. 

 Your best bet is to use a CTCSS tone like 110.9 Hz, 114.8 Hz, 156.7 Hz, 162.2 Hz, 167.9 Hz, 192.8 Hz, 203.5 Hz, 210.7 Hz, 225.7 Hz, etc. or a random DCS code.  A channel plan could look like this:


CH 01 - 151.8200 MHz [TX CTCSS: 156.7 Hz] [RX CTCSS: 156.7 Hz] - Scrambler Mode 2
CH 02 - 151.8800 MHz [TX CTCSS: 156.7 Hz] [RX CTCSS: 156.7 Hz] - Scrambler Mode 4
CH 03 - 151.9400 MHz [TX CTCSS: 156.7 Hz] [RX CTCSS: 156.7 Hz] - Scrambler Mode 6
CH 04 - 154.5700 MHz [TX CTCSS: 156.7 Hz] [RX CTCSS: 156.7 Hz] - Scrambler Mode 3
CH 05 - 154.6000 MHz [TX CTCSS: 156.7 Hz] [RX CTCSS: 156.7 Hz] - Scrambler Mode 5

CH 06 - 151.8200 MHz [TX CTCSS: 156.7 Hz] [RX CTCSS: 156.7 Hz] - Scrambler OFF
CH 07 - 151.8800 MHz [TX CTCSS: 156.7 Hz] [RX CTCSS: 156.7 Hz] - Scrambler OFF
CH 08 - 151.9400 MHz [TX CTCSS: 156.7 Hz] [RX CTCSS: 156.7 Hz] - Scrambler OFF
CH 09 - 154.5700 MHz [TX CTCSS: 156.7 Hz] [RX CTCSS: 156.7 Hz] - Scrambler OFF
CH 10 - 154.6000 MHz [TX CTCSS: 156.7 Hz] [RX CTCSS: 156.7 Hz] - Scrambler OFF

CH 11 - 151.8200 MHz [TX CTCSS: 156.7 Hz] [RX CTCSS: OFF] - Scrambler OFF
CH 12 - 151.8800 MHz [TX CTCSS: 156.7 Hz] [RX CTCSS: OFF] - Scrambler OFF
CH 13 - 151.9400 MHz [TX CTCSS: 156.7 Hz] [RX CTCSS: OFF] - Scrambler OFF
CH 14 - 154.5700 MHz [TX CTCSS: 156.7 Hz] [RX CTCSS: OFF] - Scrambler OFF
CH 15 - 154.6000 MHz [TX CTCSS: 156.7 Hz] [RX CTCSS: OFF] - Scrambler OFF



The TH-9000D series of radios have 8 different scrambler settings (OFF, 1, 2, 3, 4, 5, 6, 7, 8 and UDF).  UDF is "user-defined" and defaults to the same as OFF or unscrambled clear transmissions.  Make sure both radios are set for the same scrambler mode (you can choose whichever one you want, and you could use a different setting for each channel to increase security).  It is important to program the MURS channels in without scrambling turned on - especially in a SHTF situation, you will want to, at the very least, monitor other MURS radio chatter in the area. 

As far as the CTCSS / DCS settings go - you can use whichever one you like, just avoid the common ones I listed in the previous paragraphs - and make sure that both radios are programmed for the same CTCSS or DCS code for a given channel.  You don't have to use the same CTCSS or DCS tones/codes for each channel, you can mix it up.  CTCSS and DCS do not provide any sort of privacy.  They simply reduce interference by ignoring all transmissions that do not have the same CTCSS or DCS code that your radio is set in the receive mode for. 

You could then program in the other VHF business band frequencies, the public safety frequencies and the 7 NOAA Weather frequencies in as you desire.  The TH-9000D has 200 channels which is more than enough for your purposes. 

You may also want to consider programming the MURS channels in with the power output set to LOW and then programming them in with the power set to HIGH.  Low power mode reduces your chance of interception by a distant receiver and for car-to-car communications the 10 watt low power setting usually works just fine.  In my experience with the TH-9000D (I have owned and do currently own several of them) is that the low power setting is generally 8-12 watts, medium power is around 25-27 watts and high power is 65-70 watts.  These minor variations make very little real-world difference.  However, if your wife is only a mile or two away from you, you don't need to be transmitting 70 watts to talk to her.  Use high power when maximum range is required. 


Make sure you set the radio to 12K bandwidth mode (narrowband FM) when you program the TH-9000 radios.  They default out of the box to 20K or 25K which are both wideband FM settings.   

Program the MURS frequencies in as well as the VHF business band itinerant frequencies and the VHF public safety interoperability channels.  Those are good for monitoring in an emergency as well.  Everything except for the NOAA Weather Channels and 2 meter ham frequencies (do NOT use 2 meters if you don't have a ham license) should be in narrowband (12K or 12 kHz) mode.   The VHF interoperability channels should be programmed in CSQ or carrier squelch receive, same with the business band frequencies.  Stick with MURS for your purposes - the other channels are good for monitoring other preppers/users in your area. 


VHF Business / Prepper / Militia / Patriot VHF High Band
    151.6250 MHz - Militia/Patriot VHF BUSINESS RED DOT 1
    151.9550 MHz - Militia/Patriot VHF BUSINESS PURPLE DOT 2
    152.8850 MHz - Militia/Patriot VHF BUSINESS 3
    152.9150 MHz - Militia/Patriot VHF BUSINESS 4
    151.7000 MHz - Militia/Patriot VHF BUSINESS 5
    151.7600 MHz - Militia/Patriot VHF BUSINESS 6
    151.9250 MHz - Militia/Patriot VHF BUSINESS 7
    151.8350 MHz - Militia/Patriot VHF BUSINESS 8
    151.8050 MHz - Militia/Patriot VHF BUSINESS 9
    151.5125 MHz - Militia/Patriot VHF BUSINESS 10
    151.6550 MHz - Militia/Patriot VHF BUSINESS 11
    151.6850 MHz - Militia/Patriot VHF BUSINESS 12
    151.7150 MHz - Militia/Patriot VHF BUSINESS 13
    151.7450 MHz - Militia/Patriot VHF BUSINESS 14
    151.7750 MHz - Militia/Patriot VHF BUSINESS 15
    151.8650 MHz - Militia/Patriot VHF BUSINESS 16
    151.8950 MHz - Militia/Patriot VHF BUSINESS 17
    151.9250 MHz - Militia/Patriot VHF BUSINESS 18
    151.5050 MHz - Militia/Patriot VHF BUSINESS 19
    154.4900 MHz - Militia/Patriot VHF BUSINESS 20
    154.5150 MHz - Militia/Patriot VHF BUSINESS 21
    154.5275 MHz - Militia/Patriot VHF BUSINESS 22
    154.5400 MHz - Militia/Patriot VHF BUSINESS 23
    153.0050 MHz - Militia/Patriot VHF BUSINESS 24
    154.6550 MHz - Militia/Patriot VHF BUSINESS 25
    158.4000 MHz - Militia/Patriot VHF BUSINESS 26
    158.4075 MHz - Militia/Patriot VHF BUSINESS 27

The MURS frequencies are also included in the channel plan above, I omitted them since you're going to be programming them in anyway.  MURS 3 is generally considered to be the "primary" or "calling" frequency. 


Since you're in New York, you should also program in these New York state specific frequencies (again, for monitoring/listening purposes)

154.6950 MHz - New York State Police Statewide Emergency/Broadcasts Channel
154.6650 MHz - New York State Police Car-to-Car
155.3700 MHz - New York Statewide Public Safety interop (included below with interop frequencies)

https://www.radioreference.com/apps/db/?aid=615 - for the NYSP frequencies - I would include the ones local to you as well as the ones surrounding you.

VHF Public Safety Interoperability

155.7525 MHz - VCALL10 - Public Safety VHF Calling
151.1375 MHz - VTAC11/VTAC36 - Public Safety VHF Operations
154.4525 MHz - VTAC12/VTAC37 - Public Safety VHF Operations
158.7375 MHz - VTAC13/VTAC38 - Public Safety VHF Operations
159.4725 MHz - VTAC14/VTAC39 - Public Safety VHF Operations
155.3700 MHz - Law Enforcement Intersystem - often called "INTERCITY"
155.4750 MHz - VLAW31 - Nationwide VHF Law Enforcement Interoperability
155.3400 MHz - VMED28 a.k.a. "HEAR" "HEAR340" - Hospital/EMS/Medical Interop
154.2800 MHz - VFIRE21 - Fire Interop
154.2650 MHz - VFIRE22 - Fire Interop
154.2950 MHz - VFIRE23 - Fire Interop
« Last Edit: February 12, 2020, 1459 UTC by R4002 »
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Offline R4002

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Re: 11 meter private comms?
« Reply #19 on: February 12, 2020, 1149 UTC »
Make sure you get high quality antennas to use with your TYT TH-9000D radios as well.  I use a Browning BR-168-S (the all-black version which is the BR-168-B-S) 1/2 wave mobile antenna.  It provides broadband performance across the VHF band.  I also have a couple 5/8 wave mobile antennas...but with the 5/8 wave you MUST tune and cut the antenna for the frequency you intend to use.  1/2 wave and 1/4 wave antennas tend to give much better out-of-the-box SWR.  5/8 wave antennas will give you more gain compared to the 1/2 wave antenna but you WILL need to get a decent quality VHF or VHF/UHF SWR meter and cut the whip accordingly. 

The 1/2 wave antenna like the BR-168 gives 2.4db gain (compared to the 3db gain the 5/8 wave gives you) without as much tuning hassle. 

I recommend using a trunk lip mount antenna if possible.  Magnetic mount antennas work well too, but a more permanent mount is more durable and will generally provide better performance.  An antenna mounted on the roof of your vehicle will work better than a fender or trunk or hood mount.  Which types of vehicles will you be installing the TH-9000D radios in? 
« Last Edit: February 12, 2020, 1454 UTC by R4002 »
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Offline 45auto

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Re: 11 meter private comms?
« Reply #20 on: February 12, 2020, 2003 UTC »
 Dear R4002,
   Wow, I am grateful for getting the same TYT radio, proof of high quality!  Ha Ha!
   Lots of great info, changing the Scrambler code is very clever too.
   I have some homework to do.
   Yikes!

     PS:  Yes there are annoying data bursts on MURS 1, 2 and 3. 
               Habitual.   I assume they are the new VHF dog collars with GPS.
              Also the "Alert Zone 2" garbage.   Ugh!
     

Offline R4002

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Re: 11 meter private comms?
« Reply #21 on: February 13, 2020, 1415 UTC »
45auto,

Yep, the data bursts on MURS could be any number of things.  In my area, there are several telemetry systems that use the MURS channels.  They appear be related to industrial sites located 1-2 miles away.  I know that dog collars and hunting dog tracking systems use the MURS channels as do the driveway alert and security alert systems.  There are numerous other systems that use the MURS channels.  Luckily, you will be able to program in a CTCSS or DCS tone/code for your radios and those will filter out the annoying interference. 

I sent you a PM as well with more detailed information on how to implement CTCSS to eliminate the interference on the MURS frequencies as well as other detailed information for your purposes. 
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Re: 11 meter private comms?
« Reply #22 on: February 13, 2020, 1742 UTC »
There is also GPS survey equipment that transmit data via MURS channels back to the data collector.

The "alert zone x" announcements are from Dakota Alert driveway alarm products. I have them on my driveway.

https://www.dakotaalert.com/store/murs-alert-products/
- Rob

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Offline R4002

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Re: 11 meter private comms?
« Reply #23 on: February 13, 2020, 2150 UTC »
Exactly.  Thereís a couple of these data link networks that send a packet every 2-3 seconds and it can get extremely annoying...itís 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. Iím 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.
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Offline 45auto

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Re: 11 meter private comms?
« Reply #24 on: March 02, 2020, 1541 UTC »
 Mr Stretchyman has this correct with quote  "PRIVATE & 11m don't quite go together...." 
 
   I was reflecting on what if?   What if the BIG ONE should strike, and all internet & cell phones should crash.
   CB radio would be the temporary filler, everyone would dive into their attics and retrieve grandpa's Cobra.
   All 40 channels would be saturated with AM signals, no room for SSB!! 
   This is one reason my wife and I choose VHF, with a CB locked in the trunk just in case. Ha Ha LOL!   

      45auto in Western NY 

Offline ThaDood

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Re: 11 meter private comms?
« Reply #25 on: March 02, 2020, 1828 UTC »
If you want to protect computers, iPads,loaded USB thumb drives, hard drives, and radios, from EMP's, store them in a trashed microwave oven. Yep, everyone out there has a Faraday Cage. When the megnetron blows up, just cut the line cord, take out the trays, and thar' ya iz, a free Faraday Cage to store static and pulse sensitive electronics. Back to digital packet bursts on MURS, in rural areas gas, electric, H2O, and other utilities, use that band a lot, and data transmissions are legal there. And yes, if you listen to some of those bursts while mobile, some of those carry for over +10 miles. On voice just about every Walmart uses CH's 4 and 5. One Walmart that I know is located on a hill, I've heard their employees from +5 miles away just using HT's. BTW, in WNY MURS CH1 was very popular from Buffalo, and some very early mornings, they could be heard down by the Pennsyl-tucky border via Tropo.(Not Pennsylvania. If you've been to Mckeen, Warren, Potter, and Tioga, counties, then you'll know what I mean. Hi-hi...) But, VHF MURS goes where 2M HAM does, and DX up by Lake Erie is inevitable. (Neat, but bare that in mind.) Also, in the land of P.O.O. (Province Of Ontario in Canada.), you will hear EMS and business tone out from there. I was able to hear London, ON ambulance tone out on MURS CH3 from about 160 miles away. Just some perk, and jerks, to consider.
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Offline Josh

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Re: 11 meter private comms?
« Reply #26 on: March 02, 2020, 2132 UTC »
A metal garbage bin is far better suited as emp proofing than a microwave, but "you run what you brung" as the racecar drivers say.
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Offline chanito

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Re: 11 meter private comms?
« Reply #27 on: March 19, 2020, 1832 UTC »

a combination of 300+ watt amplifiers and Pig Latin should do the trick.


Or, this expensive gadget. http://www.rowetel.com/?page_id=3902
« Last Edit: March 19, 2020, 1839 UTC by chanito »
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Offline R4002

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Re: 11 meter private comms?
« Reply #28 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. 
U.S. East Coast, various HF/VHF/UHF radios/scanners/receivers