Missing CTCSS codes on some older radios?

[TrikeRadio]

I was looking at the manuals of two OLD GMRS radios I had years ago. They were both of the "bubble pack" variety.
(Midland GXT1050VP4 ) and a (MOTOROLA MR356R)

Both of these just had the numbered "privacy codes" (yeah I know) that are just numbered 1 - 38 in the radio, but the hz values for these codes are listed in the manual.

I currently have a TD-H3 which does not have "codes" but uses the actual hz values to select your tones.
I then noticed that there are several tones that are "skipped" by the older radios...
69.3
159.8
165.5
171.3
183.5
189.9
196.6
199.5
206.5
229.1
254.1

It really is not a big deal but I was wondering:

* why dont' those older radios have those tones.
* Were they really just so short on memory that they could not have these 12 more codes?

I sometimes use my TD-H3 with people who are just using FRS handhelds.
* Do current FRS radios also omit these same tones or maybe others too?

Just wondering if anyone knows why these are missing or if it is purely up to the maker of the radio (and if so, why did these Motorola and Midland radios skip the same ones?)

Maybe it was an older standard?

Thanks if anyone has any answers to these.
Again, not a big deal but it was a curiosity that I noticed when comparing my old radios to this one.
 

[WRUU653]

1 hour ago, TrikeRadio said:

I was looking at the manuals of two OLD GMRS radios I had years ago. They were both of the "bubble pack" variety.
(Midland GXT1050VP4 ) and a (MOTOROLA MR356R)

Both of these just had the numbered "privacy codes" (yeah I know) that are just numbered 1 - 38 in the radio, but the hz values for these codes are listed in the manual.

I currently have a TD-H3 which does not have "codes" but uses the actual hz values to select your tones.
I then noticed that there are several tones that are "skipped" by the older radios...
69.3
159.8
165.5
171.3
183.5
189.9
196.6
199.5
206.5
229.1
254.1

It really is not a big deal but I was wondering:

* why dont' those older radios have those tones.
* Were they really just so short on memory that they could not have these 12 more codes?

I sometimes use my TD-H3 with people who are just using FRS handhelds.
* Do current FRS radios also omit these same tones or maybe others too?

Just wondering if anyone knows why these are missing or if it is purely up to the maker of the radio (and if so, why did these Motorola and Midland radios skip the same ones?)

Maybe it was an older standard?

Thanks if anyone has any answers to these.
Again, not a big deal but it was a curiosity that I noticed when comparing my old radios to this one.
 

I have some old Motorola FRS bubble pack talkabouts and I am fairly certain they are missing these too. This makes it fun for putting in PL tones by number, better to know the Hz. Motorola Tones .pdf 

[Lscott]

1 hour ago, WRXP381 said:

No there is no industry standard.  So what.   Does it really matter.  Some brand new radios don’t have all the tones of some other radios.  So what? 

Trying to coordinate a group using different radios with different numbering schemes for the tones you learn real quick why it matters. I frequently read posts on the forum where this is a consistent complaint.

[SteveShannon]

2 hours ago, WRXP381 said:

No there is no industry standard.  So what.   Does it really matter.  Some brand new radios don’t have all the tones of some other radios.  So what? 

Sure there is: EIA/TIA-603-E

[TrikeRadio]

It is no wonder that sometimes getting older GMRS tones and FRS radio users to get the correct tone set is such a pain.

The 69.3hz tone is essentially the second option on my TD-H3...
     but if you choose the code 2 on the older radios... that is not the same tone ... it would be 71.9hz!

I can understand them skipping tones at the end of the list if they were trying to save space... but to not include the second tone ... just because... messes up the count for basic FRS users who don't understand it.

 

[amaff]

22 minutes ago, TrikeRadio said:

It is no wonder that sometimes getting older GMRS tones and FRS radio users to get the correct tone set is such a pain.

The 69.3hz tone is essentially the second option on my TD-H3...
     but if you choose the code 2 on the older radios... that is not the same tone ... it would be 71.9hz!

I can understand them skipping tones at the end of the list if they were trying to save space... but to not include the second tone ... just because... messes up the count for basic FRS users who don't understand it.

 

That's why I love the 1 button frequency / tone scan on the H3. They can be on whatever channel and tone, and you should be able to set the frequency scan going and have them transmit and it'll tell you what they're on (hold down the 1 button)

[TrikeRadio]

6 minutes ago, amaff said:

That's why I love the 1 button frequency / tone scan on the H3. They can be on whatever channel and tone, and you should be able to set the frequency scan going and have them transmit and it'll tell you what they're on (hold down the 1 button)

Yeah, that is a great function. It does make it easier.

[amaff]

But yeah, it doesn't seem that there's a true industry standard list of tones. And I hate having to have a lookup sheet for 'codes' or 'subchannels' or whatever they want to call them vs just saying what the tone is and being done w/ it.

[SteveShannon]

3 hours ago, TrikeRadio said:

It is no wonder that sometimes getting older GMRS tones and FRS radio users to get the correct tone set is such a pain.

The 69.3hz tone is essentially the second option on my TD-H3...
     but if you choose the code 2 on the older radios... that is not the same tone ... it would be 71.9hz!

I can understand them skipping tones at the end of the list if they were trying to save space... but to not include the second tone ... just because... messes up the count for basic FRS users who don't understand it.

 

Motorola invented PL tones, other companies added tones. There’s more to it than simply picking tones out of a hat. Read the history on Wikipedia:

https://en.m.wikipedia.org/wiki/Continuous_Tone-Coded_Squelch_System

[TrikeRadio]

20 minutes ago, SteveShannon said:

Motorola invented PL tones, other companies added tones. There’s more to it than simply picking tones out of a hat. Read the history on Wikipedia:

https://en.m.wikipedia.org/wiki/Continuous_Tone-Coded_Squelch_System

Thanks Steve, I guess I shoulda thought to check Wikipedia. Interesting to read about how it works too.

[amaff]

8 hours ago, SteveShannon said:

Sure there is: EIA/TIA-603-E

You're of course correct, there is a standard list. But not all manufacturers use the entire list, is probably how I should have worded it. No manufacturer is out here picking and choosing numbers at random, thankfully (that I've seen at least...), but tone 1 on one radio isn't necessarily tone 1 on another radio, and that tends to trip people up.

[SteveShannon]

37 minutes ago, amaff said:

You're of course correct, there is a standard list. But not all manufacturers use the entire list, is probably how I should have worded it. No manufacturer is out here picking and choosing numbers at random, thankfully (that I've seen at least...), but tone 1 on one radio isn't necessarily tone 1 on another radio, and that tends to trip people up.

My reply wasn’t intended to disagree with you.  You’re right that the ordering or labeling of the tones on different brands of radios is not standardized, even if the tones themselves are. Fortunately most radios now simply list the frequency rather than an abstract label. And some tones are not included for technical reasons. The 100 Hz tone is sometimes not included in some countries because it’s exactly twice the frequency of the 50 Hz electric system and there were concerns that interference from power lines could open squelch inadvertently.

My old Motorola Talkabouts, Midland GXT1000s, and even my newer Garmin still uses labels.  Fortunately I only needed to set those older GMRS radios once; our rocketry club settled long ago on channel 7 tone 6 (which appears to be the same across different radios). 
My Wouxun kg805 uses frequencies; i haven’t played with it much.  All of my amateur handhelds (mostly Yaesu but a couple Baofengs, one Alinco, and one TYT) present the actual frequencies in ascending order. That’s easier to understand than the labeled tones.

[Lscott]

40 minutes ago, amaff said:

You're of course correct, there is a standard list. But not all manufacturers use the entire list, is probably how I should have worded it. No manufacturer is out here picking and choosing numbers at random, thankfully (that I've seen at least...), but tone 1 on one radio isn't necessarily tone 1 on another radio, and that tends to trip people up.

A few of my commercial radios allow the entry of custom tones. That would really bugger somebody up. Might be a way to keep unauthorized people from using a repeater, provided you can enter non-standard tones into it.  

[amaff]

3 minutes ago, Lscott said:

A few of my commercial radios allow the entry of custom tones. That would really bugger somebody up. Might be a way to keep unauthorized people from using a repeater, provided you can enter non-standard tones into it.  

 

My $100 DB20-G also allows this. As do my $40 TD-H3s, now that I just tried punching something weird in (and verified it actually stuck... it wouldn't break squelch until I set the custom tone on the other handset).

[Lscott]

Just now, amaff said:

My $100 DB20-G also allows this. As do my $40 TD-H3s, now that I just tried punching something weird in (and verified it actually stuck... it wouldn't break squelch until I set the custom tone on the other handset).

Cool! Good way to keep annoying people from disrupting your communications. Even if scanning showed the custom tone if the user can't enter it in their radio they're hosed.

[amaff]

2 minutes ago, Lscott said:

Cool! Good way to keep annoying people from disrupting your communications. Even if scanning showed the custom tone if the user can't enter it in their radio they're hosed.

It would be, in a pinch. My nicer HTs (KG-905Gs) I don't believe I can do custom tones (maybe through the software, but definitely not on the radio), and I like for all my stuff to be set up more or less the same so they'll all talk to each other, obv. Thankfully I've not had to deal with that sort of nuisance before.

[Lscott]

1 minute ago, amaff said:

It would be, in a pinch. My nicer HTs (KG-905Gs) I don't believe I can do custom tones (maybe through the software, but definitely not on the radio), and I like for all my stuff to be set up more or less the same so they'll all talk to each other, obv. Thankfully I've not had to deal with that sort of nuisance before.

It's nice to know you have the ability if necessary.

[TrikeRadio]

1 hour ago, amaff said:

My $100 DB20-G also allows this. As do my $40 TD-H3s, now that I just tried punching something weird in (and verified it actually stuck... it wouldn't break squelch until I set the custom tone on the other handset).

Oh... wow. I have TD-H3s too and ... I didn't realize I could enter custom values into the CTCSS fields! I thought it only let you scroll up and down to select them.
I tried it and I was also able to enter any number I wanted like you. Thanks! Great to know that is possible since three other friends of mine also have the same radios.

[WRUU653]

 

3 hours ago, Lscott said:

It's nice to know you have the ability if necessary

I can’t believe I’ve never tried this before. It may not be that uncommon as I was able to do this with Wouxun UV9PX, KG-Q10H, KG-S88G and Baofeng UV-9G.

Nice to know indeed.

edit: add the KG-935Plus to the list 

Edited August 5 by WRUU653
Additional information

[tweiss3]

Squelch tones weren't always a thing. 

Also, the use of non-standard tones have been used as an effort to manufacturer lock systems without writing it specs as single source. A practice that is still going strong even as pubic agencies all drift to trunked digital systems.

It should also be noted that most manufacturers don't care at all if their packs of radios are compatible with another manufacturer, they would rather you buy another pack of their radios due to "incompatibility".

I haven't spent any time testing with nonstadard tones, but I know Harris will allow any time typed in. I'm sure there may be a problem with selectivity between 141.8 and 141.6. it would be an interesting bench test. 

It's easier to either:

1) Make sure every one in your party knows their own radio and service a standard for your group, or

2) Carry enough radios you can hand one out (pre programmed) to everyone.

 

[Lscott]

This is a rather long article but covers the topic of tone squelch systems rather well. 

https://www.repeater-builder.com/tech-info/ctcss/ctcss-overview.html

And this thread on another forum has a brief discussion of why the tones are such odd values.

https://ham.stackexchange.com/questions/1913/why-are-pl-tones-strange-numbers

[Lscott]

Digital Coded Squelch is a whole different animal. The attached file goes into some detail on how that all works.

DPL _ DCS Squelch System.pdf

[Socalgmrs]

No there is no industry standard.  So what.   Does it really matter.  Some brand new radios don’t have all the tones of some other radios.  So what?