HFU HF Underground
Loggings => 10/11 meters => Topic started by: 45auto 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.
-
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.
-
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.
-
The cheapest and best against the milieu would be v/uhf with voice inversion.
-
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
-
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
-
https://www.wearecb.com/speech-inversion-scrambler.html
If you want to use 11 meter or freebands, you should check this out, too.
-
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.
-
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.
-
Great posting R4002 !
-
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.
-
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).
-
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!
-
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).
-
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 (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.
-
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.
-
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.
-
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.
-
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
-
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?
-
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!
-
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.
-
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/
-
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.
-
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
-
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.
-
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.
-
a combination of 300+ watt amplifiers and Pig Latin should do the trick.
Or, this expensive gadget. http://www.rowetel.com/?page_id=3902
-
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.