UHF RAdio Users - Compatibility Information

[Cobrajr122]

Antenna length is a massive factor in the effectiveness of a radio.

On another note, unless you have an armature radio license, you should not be operating in the HF/VHF range.... nor any frequency outside of the FRS/GMRS frequencies.

[Harvath]

Originally Posted by MadMorbius

Putting it all together

So, if you are using a UHF radio configured to access the 462-468Mhz band for FRS / GMRS access, and you've been directed to use FRS channel 14-21, you would set your transeiver to 467.7125 with CTCSS tone 136.5.


Hope this helps.

Just curious why you would use that frequency and that CTCSS tone?

Also how do you use the CTCSS tones on these higher end radio's? I have the Motorola HT1250.

[DustMagnet]

Originally Posted by Harvath

Just curious why you would use that frequency and that CTCSS tone?

Because that's the frequency for FRS channel 14 and the frequency for CTCSS Tone 21.

However, I've heard that frequency assignments for CTCSS may not be identical across manufacturers.

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[Harvath]

Ah thanks, that makes sense now, I thought it was Ch Service Frequencies 14-21. Now I have to figure out how to get the Code Freq on my Motorola HT1250. You wouldn't know how would you DustMagnet?

[DustMagnet]

Originally Posted by Harvath

Ah thanks, that makes sense now, I thought it was Ch Service Frequencies 14-21. Now I have to figure out how to get the Code Freq on my Motorola HT1250. You wouldn't know how would you DustMagnet?

Sorry, I don't.

[Drake]

In my experience, "sub-channels" (CTCSS squelch) is rarely used since it's difficult to set on the fly on many radios: it requires either re-programming a channel with the correct CTCSS frequency, or manually setting the Rx/Tx frequency and CTCSS frequency -- which can lead to errors, specially when trying to change channels in the thick of battle, and transmitting on channels you shouldn't be on.

Additionally, some radios (like Motorolla Sabres) have to be reprogrammed by computer and I think they don't even support CTCSS.

Originally Posted by DustMagnet

However, I've heard that frequency assignments for CTCSS may not be identical across manufacturers.

What changes sometimes is the assigned "sub channel" number representing a given CTCSS tone frequency.

Here's a good example of it: http://www.popularwireless.com/codetable.html

So to re-use Morb's orginal example, for some people sub-chan 21 would actually be 22 on their radios. So its important to be aware of your radio's specs.

[Harvath]

Okay, DustMagnet mentioned that, I'm going to the Nightfall 2 game and I really hoping they stay simple with frequencies until I can really figure it out. Still need to test it out though.

Thank you both for your input, you both put this more into layman's terms than most articles I have read.

[Harvath]

Originally Posted by

Amateur radios operating in the GMRS or FRS frequency range can be configured to use CTCSS "Sub Channels" by configuring the CTCSS tone frequency.

[b

The following is a list of sub-channel CTCSS frequencies:[/b]

Code Freq (Hz)
1 67.0
2 71.9
3 74.4
4 77.0
5 79.7
6 82.5
7 85.4
8 88.5
9 91.5
10 94.8
11 97.4
12 100.0
13 103.5
14 107.2
15 110.9
16 114.8
17 118.8
18 123.0
19 127.3
20 131.8
21 136.5
22 141.3
23 146.2
24 151.4
25 156.7
26 162.2
27 167.9
28 173.8
29 179.9
30 186.2
31 192.8
32 203.5
33 210.7
34 218.1
35 225.7
36 233.6
37 241.8
38 250.3



Putting it all together

So, if you are using a UHF radio configured to access the 462-468Mhz band for FRS / GMRS access, and you've been directed to use FRS channel 14-21, you would set your transeiver to 467.7125 with CTCSS tone 136.5.


Hope this helps.

I know these frequencies are part of the CTCSS frequencies but there are many more which intermingle with the ones listed above, so I ask did you take these from a personal GMRS/FRS radio or is this what you have found most people use here in Canada or at least Ontario.

I have a Motorola HT1250 radio and I'm trying to get it set up. I am having to have it sent out to have it done and the person setting it up needs to know the exact frequencies used otherwise it won't work.

How do you have your radio set up?

Thank you,

[Drake]

Originally Posted by Harvath

I know these frequencies are part of the CTCSS frequencies but there are many more which intermingle with the ones listed above, so I ask did you take these from a personal GMRS/FRS radio or is this what you have found most people use here in Canada or at least Ontario.

I have a Motorola HT1250 radio and I'm trying to get it set up. I am having to have it sent out to have it done and the person setting it up needs to know the exact frequencies used otherwise it won't work.

How do you have your radio set up?

Thank you,

CTCSS are tone frequencies, not radio (Rx/Tx) frequencies, i.e., they're literally an [inaudible to human ears] tone being transmitted at the same time as your communication. They're set up by manufacturers, and while certain standards have been adopted by different manufacturers they aren't identical/100% compatible across the board -- which leads to the above example where certain "sub-channels" use different tones depending on brands.

In the case of programmable radios (like Puxing, Linton, etc) CTCSS ton frequencies can be defined directly on the radio (vs. a FRS radio where you can't program anything and you have to use whatever CTCSS tones came with the radio). But as mentioned, I don't see them get used that often anymore cuz they're a PITA and aren't that useful.

[FlyGuy]

Let's be crystal clear right here and right now:

Possession and use of ANY radio apparatus not specifically certified under Industry Canada's RSS-210 (as license-exempt) or under RSS-119 (with a license issued by IC) on FRS/GMRS frequencies is contrary to s.4.1 of the Radiocommunication Act.

The only "approved/legal" radios for FRS/GMRS are indeed those blister-packaged ones you find at Wal-Mart and Cdn. Tire, etc. That being said, it is not practical for IC to go after everyone using one of those imported "amateur-type" radios on the FRS/GMRS allocation. So unless you decide to deviate from those frequencies and go off looking for your own "clear channel" which may in fact not be clear at all and thus quickly attract IC's undivided attention by causing harmful interference to someone else, your chances of getting caught with a non-approved radio strictly on FRS/GMRS are somewhere between slim and none.

Now then...back to your radio:
Your MOT HT1250 radio does not have a front panel program (FPP) option available for it so it MUST be programmed entirely via Motorola's CPS software, which you've stated you have someone doing for you. The problem for you w/respect to CTCSS tones is that along with the FRS/GMRS specific frequencies which need to be placed into the radio's codeplug, you may only specify one out of the available forty-two "PL" (Mot-speak for CTCSS) tones at a time on a per-frequency basis. Unlike amateur radios, of which all these imported Chinese "Kenwood clones" (Woxoun, Puxing, etc.) are, you cannot simply change the CTCSS tone at-will on the fly with your HT1250. It must be pre-programmed for each frequency listed in your codeplug. If you need to change a tone for a particular frequency, you need to have the radio re-programmed. NOT very convenient but...

...Commercial radios intended for the land mobile (non-amateur) service were never authorized by Industry Canada to have direct frequency entry and control of radio programming features such as CTCSS tone select. FRS/GMRS has a slight exception in that CTCSS tones are accessible to the users but the frequencies are "channelized" rather than allowing direct entry. This was done to force responsibility for proper radio provisioning and a significant level of accountability to the regulator onto the radio suppliers. This prevented the largely ignorant (of radio spectrum) radio users from being able to, among other things, arbitrarily dial-in a new operating frequency of their own which obviously would create no end of interference problems for both the regulators and for other licensed users. There are radios where this front panel programming and control capability was part of the design and the radios were certified for use by IC. However, authorization for possession and use of these types of radios was severely restricted and limited to special cases such as public safety, government, etc. Your HT1250 is not among those types of radios.

About CTCSS:
Your assertion that, "...many more intermingle..." belies your lack of understanding or knowledge about two-way radio. Your HT1250 was manufactured by Motorola and as such, will only use CTCSS or PL tones if you prefer Motorola's vernacular, which they support. You can find a list here if you're interested.

AND FINALLY, as Drake has already put it rather well, the manufacturer's differences combined with the inconvenience of programming/changing CTCSS simply out-weighs any real benefit to using it in the context of airsoft games. CTCSS was designed to allow multiple and different users to tx/rx on the same radio frequency without necessarily having to endure each other's transmissions. In airsoft, entire teams are typically assigned a single FRS/GMRS radio channel or set of channels - there's enough available. Therefore, the only people you're going to hear are your own team mates so tone coded squelch becomes rather irrelevant at that point.

Just have your radio guy correctly program the FRS/GMRS frequencies into your radio and leave out the CTCSS tones. You will be happier that way.


"Ready...FIRE...aim!"
Fly

[Harvath]

Drake and Flyguy, thank you, if this is the case then there is no need for me to put in the CTCSS codes and I will just put in the 22 frequency codes. You are right about my lack of understanding about the whole thing. Which is why it gets difficult in voicing what I am looking for.

So with that, I know my direction and this will allow me to move forward. This radio is only going to be used for airsoft and nothing more. I am not looking to breaking any laws. I just want to play and have fun.

Again, thank you

[zone 69]

Let me see if I have this right.
I have my radio set to 13FRS 467.6875 and CTCSS tone set TX 103.5 and RX 103.5
I can only transmit and receive on channel 13FRS 467.6875.
Will I be able to use other channel's or do I have to reset the CTCSS tone.

[Drake]

Originally Posted by zone 69

Let me see if I have this right.
I have my radio set to 13FRS 467.6875 and CTCSS tone set TX 103.5 and RX 103.5
I can only transmit and receive on channel 13FRS 467.6875.
Will I be able to use other channel's or do I have to reset the CTCSS tone.

It depends on the radios: if you're programming channels, then each channel will have its own CTCSS tone assigned (or disabled); if you're in "direct input" mode (arbitrarily tuning frequencies) then the CTCSS tone will usually stay to whatever you set it. Some radios (namely COTS FRS and GMRS radios, as well as a few programmable Chinese versions like the PX-888K) will let you set a CTCSS tone on a stored (programmed) channel (frequency).

So it really depends on your radio:

If you have a FRS/GMRS radio, you'll have a 103.5hz CTCSS tone set on channel 13 but none (or a different one) set on other channels;

If you have a UHF radio and you're manually entering frequencies (rather than using programmed ones) the CTCSS tone will stay set when you change frequencies;

If you have a UHF radio you've programmed, which doesn't allow easy changing of CTCSS frequencies (PX777, Motorola Sabre II, etc) then the channel either has CTCSS set to a given tone from when you programmed it, or it stays off;

If you have a UHF radio you've programmed, which allows you to set CTCSS tones on a programmed channel (PX888 etc), then you'll be able to set a 103.5hz CTCSS tone on channel 13 and it will usually be applied to only channel 13 (i.e. you can set a different one on different channels).

* note I'm citing examples for radios I know: there's a metric buttload of brands/models and I don't know the capabilities of all of em.

[zone 69]

The radio Im picking up soon is Wouxun KG-UV1P.
So your telling me I was correct in the use of CTCSS tone and it will be saved to the channel when programmed and leave the other channel's free to use with or with out CTCSS input.
What would happen if I did not set the tone to channel 13 would my transmit bleed over into other channel's. What I like to know when you say sub channel's do you mean the setting on the FRS 1,2,3,4,up to 121 I see on the talk about's and the main channel's 1-22.

Sorry if I sound like a dumb ass but I just started learning about radio's.

[FlyGuy]

Best way to think about this is to completely separate (in your mind) the CTCSS (audio tone) frequency from the (RF) transmit/receive frequency of the radio.

The CTCSS function only controls whether or not your radio's speaker will un-mute in the presence of an incoming transmission having an identical CTCSS tone. Similarly, when you transmit you need to have the identical CTCSS tone as the rest of the folks you wish to talk to or their radios will not un-mute for your transmission. This prevents your "talk group" from hearing other users not in the same group when sharing the same RF tx/rx frequency.

The RF transmit/receive frequency is just as it says...it's the frequency emitted from or received by the radio's antenna. For FRS there are 14 unique frequencies and on the "blister pack" type of radios, they are actually labelled by channel number (1-14) rather than by the actual frequency itself.

The tx/rx frequency is "radio" whereas the CTCSS is "audio" and they serve two distinctly different purposes. Do not confuse the two...

As previously pointed out, the particulars of how to "operate" CTCSS on your radio is largely specific to that radio itself. Some radios will apply your chosen CTCSS tone to all frequencies (unless you turn it off) while others will allow you the flexibility to assign individual tones (can even be different ones) to both the transmit and receive frequencies either in memory channels or on direct entry. This would obviously be a situation where you'd be obliged to RTFM...

Regards,


Fly