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Author Topic: 11 meter private comms?  (Read 1063 times)

Offline 45auto

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11 meter private comms?
« on: January 09, 2020, 0320 UTC »
  Okay, I give up.
   As a prepper, I am resigned that private comms on 11 meters will not work.
   Hoping to have CB, freeband, and a private "quiet" channel using FM -CTCSS.
   There is just too much noise to compete with.   
   If I am correct, it will become worse as the 11 yr sunspot cycle grows, Yes?   
   The FM CTCSS on 27,455 worked great, but when my wife called from afar, she was battling QRN.
   Static, birdies and spurrious emissions are tough here in western New York!   
   
      Still learning, friend 45auto.
   
   

Offline IZS4

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Re: 11 meter private comms?
« Reply #1 on: January 09, 2020, 1527 UTC »
Yes. Unfortunately in your situation, better propagation would not do you any favors when it comes to interference. There would be more people to communicate with and more information to be had  though I suppose.
Listening on an Icom-718 with a 135' OCF dipole or a RSP2.  Grundig G3 and MLA-30 when portable. When QRP I use a Hendricks PFR-3 I built. Coverage is 20,30 and 40 meters.

Offline ThaDood

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Re: 11 meter private comms?
« Reply #2 on: January 09, 2020, 1909 UTC »
Hello up in WNY! Unfortunately, there's really nothing private in using CTCSS, just to the ops using it. Everyone else tuning can hear everything that's going on, and maybe that very low BRRRRRRRRRRRRRRRRRRRR sound in your audio that the CTCSS tone puts there. (Which is not as sub-audible as people are lead to believe.) Anyway, all that CTCSS toned squelch does is keep squelched all the other traffic and noise that comes on to your transceiver. When a signal is RX'ed with that CTCSS tone that matches what your radio is set to, the squelch opens. Since 11M operations in this country don't use CTCSS tones, pretty much every 11M receiver and transceiver are wide open to listen to your COMM's. (a.k.a., they are carrier operated squelch, meaning any signal that goes up to a listener's squelch threshold level will just hear what's there.) Yep, CTCSS makes it so you don't hear everything that's on your FREQ, but anyone on your FREQ will still hear everything you TX, whether you are toned, or not. So, what's another option? There's voice scrambling out there, where a listener will hear what sounds like chickens in a feeding frenzy to others tuning in. That's employed commercially on the VHF / UHF bands, but I've yet to hear it on HF. But, I don't see why that wouldn't work. You could do DV (Digital Voice), modes like Icom's D-STAR, or Yaesu's C4FM FUSION. The Icom IC-7100 I believe can do D-STAR HF, and the Yaesu FT-991A can do C4FM FUSION there. Most CB'er will not have the ability to de'MOD DV, so that could be private for you, for a little while. However, you won't be private to some tuning HAM's, or fed monitoring stations. Oh... To answer your question on when Cycle 25 revs up? DX F2 propagated stations could indeed block your traffic, and make it so the traffic that you want on CTCSS toned is blocked out at times. Why did I go through this long winded? I wasn't too sure if you knew really how CTCSS tech worked, and my apologies, if you do. Anyway, good luck.
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Offline Josh

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Re: 11 meter private comms?
« Reply #3 on: January 09, 2020, 2010 UTC »
The cheapest and best against the milieu would be v/uhf with voice inversion.
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Re: 11 meter private comms?
« Reply #4 on: January 10, 2020, 0022 UTC »
Although not authorized for use in the US as a land mobile band, the 66-88 MHz band offers some modest level of not being easily intercepted by the general public.

https://www.ebay.com/sch/i.html?_from=R40&_trksid=m570.l1313&_nkw=66-88+mhz
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Offline 45auto

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Re: 11 meter private comms?
« Reply #5 on: January 13, 2020, 1406 UTC »
  I wish to thank the ThaDood and the others for their input!
  Yes I am fully aware of the CTCSS quirks, and how some FRS dealers promote it as privacy - Ha!
  Great words of wisdom.
  The 6 meter low band radios are curious, for only $125 with Voice Inversion too? Hmmmm!
  At this time, I am favoring VHF radios with Voice Inversion.
  Besides, there are many ham repeaters available in western NY.
  I can also monitor local fire & EMS, marine radios and NOAA weather too.

    You guys are great,  45auto

Offline Phrogman

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Re: 11 meter private comms?
« Reply #6 on: January 23, 2020, 1953 UTC »
https://www.wearecb.com/speech-inversion-scrambler.html

If you want to use 11 meter or freebands, you should check this out, too.

Offline IZS4

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Re: 11 meter private comms?
« Reply #7 on: January 23, 2020, 2329 UTC »
Interesting Phrogman. It says it fits any two-way radio, so installation must be fairly straight forward. I'm not familiar with this voice inversion/scrambling stuff, but it's always good to learn about something new.
Listening on an Icom-718 with a 135' OCF dipole or a RSP2.  Grundig G3 and MLA-30 when portable. When QRP I use a Hendricks PFR-3 I built. Coverage is 20,30 and 40 meters.

Offline R4002

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Re: 11 meter private comms?
« Reply #8 on: January 26, 2020, 1706 UTC »
Lots of the newer-generation Chinese 11m rigs come with CTCSS standard.  As mentioned, it provides zero actual privacy. 

Your best bets are using a voice inversion scrambler (as mentioned), or using digital voice on 11m (26-28 MHz), VHF low band (30-50 MHz, but be careful what frequency you use in low band) or 66-88 MHz.  I would caution against using certain bands within 66-88 MHz.  Your best bets are probably 72-73 MHz and 74-74.9 MHz.  Avoid 74.9 MHz - 75.1 MHz. 

On 11 meters you could use AM or FM voice on the zeros.  11 meter export rigs default to 10 kHz steps (26.775 MHz, 26.785 MHz, 26.795 MHz, 27.455 MHz, 27.465 MHz, etc.) - going -5 kHz to the 26.770 MHz, 27.500 MHz, 27.650 MHz, etc. frequencies would reduce casual interception.    I would avoid the popular 11m frequencies 26.285 MHz 26.555 MHz, 26.565 MHz, 26.585 MHz, 26.715 MHz, 26.725 MHz, 26.735 MHz, 26.775 MHz, 26.905 MHz, 26.915 MHz, 27.425 MHz, 27.475 MHz, 27.555 MHz and 27.635 MHz. 

It is important to remember that 27.430 MHz, 27.450 MHz, 27.470 MHz and 27.490 MHz are actually land mobile FM business frequencies.  There are only a few businesses who still use those channels, but they are out there.  Most of them do use CTCSS/PL tones.   29.710 MHz, 29.730 MHz, 29.750 MHz, 29.770 MHz and 29.790 MHz are also allocated as business frequencies, and they are used in some areas. 

As far as VHF low band goes, avoid the military/government only bands.  The VHF business bands are relatively safe, but do a search for local licenses on your prospective frequency.  The standard channel steps are 20 kHz (30.56 MHz, 30.58 MHz, 30.60 MHz, etc.) The business bands are:

30.560 MHz - 31.980 MHz
33.100 MHz - 33.400 MHz
35.020 MHz - 35.980 MHz
37.440 MHz - 37.880 MHz
42.960 MHz - 44.600 MHz
47.440 MHz - 49.580 MHz

Your safest bets are the itinerant frequencies and the 49 MHz Part 15 frequencies, which are allocated for users to use anywhere in the USA (as opposed to most licenses, which only authorize use of a specific frequency within a specific area). 

The low band VHF itinerants are:

27.490 MHz
35.040 MHz
43.040 MHz


The frequencies in-between are used by public safety and military/government users.  The military technically may use any frequency between 30.000 and 87.975 MHz.   

The following bands are military/government only:

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
46.600 MHz - 47.000 MHz
49.600 MHz - 50.000 MHz


The 49.82 MHz to 49.98 MHz band is also used by Part 15 devices and is also a great place to "hide" with high power low band radios.  The standard channels are:

49.830 MHz
49.845 MHz
49.860 MHz
49.875 MHz
49.890 MHz

The 49 MHz frequencies are largely abandoned for baby monitors/cordless phones/wireless intercoms in favor of the 1.9 MHz DECT band and the 900 MHz/2.4 GHz/5.0 GHz/5.8 GHz bands.    There are some holdouts, however. 

If you go the low band route, I recommend programming those five 49 MHz channels in, if only for short-range comms.  There are preppers who include the 49 MHz channels in their handheld low band radios for short-range portable to portable communications.  I have a set of Maxon PC-50 Part 15 portable radios that operate on the 49 MHz channels for very short range communications.  There are situations where extra range is a bigger liability than advantage.  Think "low probability of intercept".  Same goes for the 100mw CB handhelds.   

If you want to go the legit route, consider getting a Part 90 Land Mobile (Business Radio) license for one/several of the 27 MHz/29 MHz business frequencies and/or VHF low band business frequencies.  VHF low band use is few and far between in many parts of the country and clear frequencies are often easy to find.   There are militia groups that have gone this route. 

Regardless of what you decide to do - do extensive monitoring of any prospective frequency.   This includes 11 meter frequencies, low band and yes, the 66-88 MHz VHF mid band.   
« Last Edit: January 26, 2020, 1720 UTC by R4002 »
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Offline IZS4

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Re: 11 meter private comms?
« Reply #9 on: January 26, 2020, 1750 UTC »
Great posting R4002 !
Listening on an Icom-718 with a 135' OCF dipole or a RSP2.  Grundig G3 and MLA-30 when portable. When QRP I use a Hendricks PFR-3 I built. Coverage is 20,30 and 40 meters.

Offline 45auto

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Re: 11 meter private comms?
« Reply #10 on: February 06, 2020, 1502 UTC »
Dear R2004,  A huge Thank you for the new info!  Copy-paste-print!!!!   
  I am learning to avoid <30 MHZ due to the 11 year sunspot cycle, and the upcoming waves of spurrious emissions that follow.   
  That TYT low band mobile looks attractive, using itinerary frequencies.  Perhaps those 49 MHZ channels with voice inversion?
  I know my wife and family cannot avoid a determined hacker or Big Brother, but 99% of the post anarchy mauraders will be thwarted.

    - Thanks to everyone!   Wow! -45auto in Upstate NY. 

Offline R4002

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Re: 11 meter private comms?
« Reply #11 on: February 06, 2020, 1606 UTC »
45auto,

Your best bet is to have multiple bands available for your communications network.  Regular VHF/UHF frequencies (the MURS channels, the FRS/GMRS channels, etc.) are good to have in a radio as well...even if you only plan on using them to monitor other folks during an emergency. 

I recommend, at the very least, that you acquire a basic 11 meter/CB radio setup - as it will no doubt be invaluable in an emergency.  Basic 40 channel AM rigs are a good place to start (for example, the Uniden PRO 510XL or PRO 520XL) but a radio that can do SSB and the frequencies above/below the CB band is better. 

The itinerant frequencies are good places to start, but be careful and be sure to monitor any frequency you intend to use. 

The 49 MHz frequencies are basically abandoned in the vast majority of places.  If you live in a rural area you'll likely be completely fine.    If you program the five channels into your low band radio you should be able to find a free frequency regardless.  The TYT quad band radio does 26-33 MHz and 47-54 MHz as "low band".  It only does FM mode though, so don't expect to be able to talk to most CBers (since they use AM or SSB mode).  You will want to use FM on the 49 MHz frequencies and any other low band frequency. 

Voice inversion provides a level of security to prevent casual interception by folks with scanners, radios that don't support voice inversion, etc.  It's certainly better than nothing. 

It sounds like you're going with the 49 MHz option.  I know I listed the frequencies previously but here's a channel plan for you:

49 MHz:

Channel 1:  49.830 MHz
Channel 2:  49.845 MHz
Channel 3:  49.860 MHz
Channel 4:  49.875 MHz
Channel 5:  49.890 MHz

If you decide to use voice inversion, program the channels in with voice inversion on and then program them in with voice inversion off - just in case you happen to stumble upon someone else using the 49 MHz channels and want to listen to them. 

Let us know what you decide to do and we can give you more guidance.  There are a lot of low band radios available on eBay (professional grade radios like Motorola, Kenwood, Vertex, etc.) - lots of sellers offer programming as part of the sale price.  I recommend going this route because these radios are very built and extremely tough.  They're also very easy to use.  You'll want to look for Motorola radios with the 42-50 MHz "split".  Other brands use 37-50 MHz, 39-50 MHz and similar "splits" to cover that portion of the VHF low band (30-50 MHz). 
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Offline Stretchyman

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Re: 11 meter private comms?
« Reply #12 on: February 06, 2020, 1612 UTC »
Just buy a couple of DMR handsets and set them to a non standard frequency.

I still laugh at the title of the tread tho'!

Ha ha!
'It's better to give than receive' so why RX when you can TX!

                            Buy one from me, NOW!

Great discounts on ALL my transmitters if purchased via HFUnderground


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Offline R4002

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Re: 11 meter private comms?
« Reply #13 on: February 06, 2020, 1918 UTC »
That's an option.

But so is buying a couple 110 watt Kenwood or Motorola land mobile radios, programming them for 43.0000, 43.0400 and the 49 MHz frequencies and using those for mobile to mobile communications.

There are lots of folks who use high power AM (100+ watts easily) for two-way land mobile purposes in the USA.  High power 11 meter freeband (especially in the lower portions of the band, 25.615-26.955 MHz) is very popular with hunting clubs and the like in many parts of the United States.  VHF low band FM gives the best characteristics of 11m but without the interference from skip (most of the time). 
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Offline R4002

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Re: 11 meter private comms?
« Reply #14 on: February 08, 2020, 1950 UTC »
If you decide on going with a 42-50 MHz bandsplit low band radio you should program these business frequencies in along with the 49 MHz frequencies:


47.4200 MHz - American Red Cross - Nationwide Primary (146.2 Hz CTCSS/PL transmit only - CSQ receive)
47.4600 MHz - American Red Cross - Nationwide Secondary (146.2 Hz CTCSS/PL transmit only - CSQ receive)
47.5000 MHz - American Red Cross - Nationwide (146.2 Hz CTCSS/PL transmit only)
45.8800 MHz - Public Safety Interoperability LFIRE4D (156.7 Hz CTCSS/PL transmit only - CSQ receive)
45.8600 MHz - Public Safety Interoperability LLAW3D (156.7 Hz CTCSS/PL transmit only - CSQ receive)

49.8300 MHz - 49 MHz FM Channel 1
49.8450 MHz - 49 MHz FM Channel 2
49.8600 MHz - 49 MHz FM Channel 3
49.8750 MHz - 49 MHz FM Channel 4
49.8900 MHz - 49 MHz FM Channel 5

Pick a CTCSS tone for transmit and receive on the 49 MHz channels.    This will cut down on interference from other users, especially on the 49 MHz channels.  I recommend programming the 49 MHz frequencies in without CTCSS on receive as well. 

60 watt or 100/110 watt VHF low band mobiles will require good antennas for maximum range.  I recommend a NMO mounted base-loaded quarter wave antenna, Larsen makes quality antennas - look into the Larsen NMO40B or NMO40C (40-50 MHz antennas).  If you're going to just use the 49 MHz frequencies for transmit and receive, you'll want to cut the antenna per the instructions for 49.8 MHz or 49.9 MHz.  Childs Antennas is another excellent company:

https://childsantennas.com/low-band-antennas

The 42-50 MHz one is your best bet. 

With 11 meters/CB and VHF low band (and all frequencies, really), the antenna is key.  A very expensive radio is worth nothing if its connected to a poorly performing antenna.   A cheap radio connected to a great antenna will outperform a top shelf radio with a crappy antenna. 

I'm assuming you're looking to buy two radios plus antennas and mounting hardware.  NMO style mounts give you the most flexibility as far as vehicle mounting options go.  It is very important that the vehicle presents a solid ground plane to the antenna.  Larger, older vehicles and trucks do better jobs as ground planes compared to smaller sedans.  However, compact cars can work just as well with some simple modifications.  I can attest to this from personal experience.  Grounding straps connecting the hood to the fender and connecting the trunk to the fender make a world of a difference.  They will make a big difference in performance even if you're using a larger vehicle, a Jeep, SUV, etc. 
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