Hoss

What's the difference? I bought a set of dual GMRS/FRS Midland radios and I will be using them to transmit to certain FRS radio users on Channel 10. They are using Privacy Code 10, but my radio has CTCSS codes instead of privacy codes. Are they the same thing? If not, how do I figure out which CTCSS code has the same frequency as the privacy code they're using?

For example, they're on channel 10 using privacy code 10. I know that my channel 10 shares the same frequency as their channel 10 already. If I set my CTCSS code to 10 as well, will it work?

Thanks.

Commatoze

CTCSS stands for continuous tone coded squelch system, often referred to as "PL" (Motorola's trade name for Private Line). It's a set of standard continuous sub-audible tones that among other things, can open another receivers squelch alowing you voice, but not others on the same frequency , to be heard by your intended recipient. When you press the transmit, this low frequency tone is transmitted along with your voice. Privacy Codes are the same thing except the name has a more non-technical moniker. The question I can't answer at the moment is what CTCSS frequency equals a particular privacy code.

Ex: CTCSS 131.8 = Privacy Code #?
CTCSS 103.5 = Privacy Code #?

If I find that answer, I'll post it later.

Commatoze

Below is a list of the standard CTCSS frequencies. You need to cross reference these frequencies to Private Codes. Try Code #1 as 69.3, Code#2 as 71.9, etc.

CTCSS
69.3
71.9
74.4
77.0
79.7
82.5
85.4
88.5
91.5
94.8
97.4
100.0
103.5
107.2
110.9
114.8
118.8
123.0
127.3
131.8
136.5
141.3
146.2
151.4
156.7
162.2
167.9
173.8
179.9
186.2
192.8
203.5
210.7
218.1
225.7
229.1
233.6
241.8
250.3
254.1

bulabula

I'm sure they're the same. I've known folks who have used a handheld UHF ham radios to talk on FRS in a pinch.

Some radios have 50 sub-audible tones ranging from 67.0 to 254.1Hz. Others have 38 tones from 67.0 to 250.3. I would hazard a guess that they increment up from 67.0. May be dependent on the quality of the FRS/GMRS radio.

Don't forget that Privacy may be a misnomer. Nothing is really "private", its just that when using those CTCSS codes your radio's squelch will only break for that privacy code by filtering out other conversations for your listening pleasure.

In other words, if you're set to FRS channel 10 and privacy code 10, you won't hear any other chatter on channel 10 on your radio, but anyone tuned in to channel 10 with CTCSS turned off could hear multiple conversations.

edit: Nice job, Tom. I was going to do that next.

butchera

Hoss,

Take at look at this . It should have all the info you are looking for.

Google is a wonderfull thing....

Commatoze

EWwww! Different Privacy Codes depending on the brand of radio?!

Hoss

Commatoze, I have that same list of CTCSS code frequencies listed in the owner's manual for my radio, but I appreciate you posting them.

Bulabula, it's not so much privacy I'm concerned about as it is just getting on the same frequency as them so we can communicate. Based on what you said though, I should just be able to put my radio on Channel 10 and turn the CTCSS codes off and hear everything they say (as well as anything anyone else on Channel 10 says. Is that correct?? However, if I don't have code set right they might not be able to hear me??

Butch, I'll have to check out that link from home. I can't access it from work.

bulabula

My Kenwood G71 only has 38 tones, but my Icoms have 50 - go figure; who knows how many my FRS's have.

Hoss, you're correct. Its just that if you're in a large shopping center and you're on 10, then someone else shows up on 10 (both without tones), you may be stepping on each other. Those tones help to minimize that.

And yes, if they have tones activated, they will not hear any signal that doesn't have that tone embedded in it.

I just wanted to ensure that you didn't associate privacy with a false sense of encoded signal type privacy.

natstayl

Hoss, A good programmable scanner with hyperscan would help, have you got access to (borrow) one? This would help you determine what freqs the older radios are xmitting/receiving, then use the sheet that came with your new radio.
Nat

Hoss

Bulabula, these Midland 7 mile radios I just bought have 38 tones.

I don't think is going to be an issue because I suspect that the privacy codes on the FRS radios I'll be talking to are the same as the CTCSS codes on my radios....just with a different name.