TD-H3 GMRS observation: transmit issue with/without privacy code

[Imply4907]

Good day!

I apologize if this question has been asked/answered -- I did some searching and wasn't able to find anything specific to this, yet I don't believe I'm the first person to encounter this.

TLDR; I can't transmit on a second similar frequency channel with or without a "privacy code"

I know "privacy code" usage isn't private. I'm using it as a general term for using DCS/CTCSS codes to reduce hearing unwanted signals.

Equipment: I have a TIDRADIO TD-H3 (HAM version) running in GMRS mode

• The firmware version is GMRS_240817
• I can and have programmed it on Odmaster or CHIRP
• I can do some limited work on the HT itself
• I just got it this week, so I'm still a little new (Jan. 15 2025)

Intent: My younger children have some FRS radios where I used FRS/GMRS Channel 1 plus a "privacy code" to (a) reduce some of the distraction from area GMRS/FRS users (b) potentially reduce the possibility that their ears might hear something inappropriate. I'd still like to be able to switch to a regular "privacy code"-free channel when I'm away.
I want to talk to communicate with them from my TD-H3.

Situation: I can't transmit out on higher of the TD-HD3's two channels if I have a mixture of privacy code and non-privacy code for the same frequency. The radio prevents transmitting on the higher channel of the same simplex frequency. Example: If I use GMRS freq. 1 and put the "privacy code" on HT radio channel 1. I then use a "privacy code" free GMRS freq. 1 on the HT radio's channel/slot 100. I can transmit out and be heard on the FRS radio when I use HT slot 1, but can't actually transmit (and hear a rejection tone) when I use the HT radios slot 100 on the same frequency. If I make HT slot 1 clear of codes and make HT slot 100 the same frequency as channel 1, but use a "privacy code", the radio blocked me from transmitting on slot 100.

I discovered this after several hours of troubleshooting and hand-wringing. It didn't matter whether I used DCS or CTCSS. I then tried using "privacy code" on the lower radio channel and put the privacy free* on the greater channel and saw I could use a privacy code successfully. What's a little weird is that I have a repeater setup with a CT tone and the radio will transmit fine.

I don't know if this is by design or a limitation of the TD-H3 and similar firmware. For all I know, it might be a general phenomenon of TIDRADIO products.

Comparison: I have a brand new pair of Baofeng 5RMs that I would like to see if they exhibit the same phenomenon, but there are issues with the programming over the cable preventing me from quickly programming them. Maybe I'll figure out how to program them on the keypad. Observation: I get the feeling that Baofeng and TIDRADIO are basically the same manufacturer but simply different brands.

Kind regards,

Jim
Woodleaf, NC USA
WSGP797

Edited Saturday at 07:45 PM by Imply4907
clarification of the "intent" section. Edit 2: improved title. Edit 3: Corrected typo in firmware version. Edit 4: standardized language from radio channel to radio slot and used slot 100 rather than 31

[TrikeRadio]

Have you tried programming it from the keboard on the radio instead of using Odmaster? I feel like Odmaster is a abit quirky. or use Chirp to program it. what you are trying to do (use a simplex channed on GMRS1 (I assume) with a tone of some kind to elimiate other transmissions... and putting a simplex tone on channel 31 with that same frequency without tones... should work.

my only thought is that you might have input the frequency on ch 31 and it thinks you are trying to put in a REPEATER frequency and is trying to offset +5 --- and telling you that you can't transmit as a repeater on the +5 offset from GMRS1 frequency.

 

[SteveShannon]

48 minutes ago, Imply4907 said:

Side question, what's the standard way to express when I mean a channel on my radio model vs. a channel within the band? Thanks in advance.

e.g. there are 22 GMRS channels in the GMRS band. My TIDRADIO model TD-H3 handheld transceiver (HT) radio has 199 channels (which varies from model to model)

About the only way is to reference both:  “I programmed GMRS channel 16 into slot 100 on my radio, but it won’t work without setting a CTCSS tone.”

[RIPPER238]

I don't use CHIRP, I use the app or the TID software. Same with my Wouxun. App is pretty sweet on the TID's. 

 

If i had a different radio than those i would use CHIRP. 

[LeoG]

18 hours ago, Imply4907 said:

That's pretty succinct, @SteveShannon. thanks

 

I think the H3 has a limitation that you can only transmit on the 1st 54 programmable channels.  After 54 they are receive only.

[LeoG]

It's not in the owners manual.  Someone here discovered it.

[Imply4907]

What I described appears to be a limitation of the TD-H3 and not the 5RM as I just tested a similar scenario on the Baofeng.

[WRTC928]

20 hours ago, Imply4907 said:

What I described appears to be a limitation of the TD-H3 and not the 5RM as I just tested a similar scenario on the Baofeng.

I was about to tell you that I haven't had this problem on the 5RM. Is the TD-H3 a GMRS-specific radio? Sometimes the manufacturers of GMRS radios fail to consider the possibility that you might want more than one channel or more than one repeater on the same frequency.

[Imply4907]

It's the HAM version but its running in GMRS mode. I only have my GMRS license at this time.

[Imply4907]

Update: I put an inquiry in to the nice people at TIDRADIO.

[Imply4907]

5 hours ago, TrikeRadio said:

Have you tried programming it from the keboard on the radio instead of using Odmaster? I feel like Odmaster is a abit quirky. or use Chirp to program it. what you are trying to do (use a simplex channed on GMRS1 (I assume) with a tone of some kind to elimiate other transmissions... and putting a simplex tone on channel 31 with that same frequency without tones... should work.

my only thought is that you might have input the frequency on ch 31 and it thinks you are trying to put in a REPEATER frequency and is trying to offset +5 --- and telling you that you can't transmit as a repeater on the +5 offset from GMRS1 frequency.

 

Thats interesting. Almost like the fact that I have a repeater frequency (radio channel 26) in the line of channels in between my channel 1 and my channel 31 that is interfering with my ability to TX on 31?

 

(thanks for considering my situation!)

as a workaround, I moved to the low powered GMRs/FRS channels in the 8-15 range since I use those less. I don’t have any custom repeaters sharing that channel. I’m having a hard time explaining it. 
 

last night I used CHIRP over a USB cable and tried a few things with duplex off and what have you before I moved to the FRS channel range that so mentioned in the previous paragraph. 
 

BTW, TIDRADIO has not replied to my request. I gave them the URL to this post. 

[TrikeRadio]

6 hours ago, Imply4907 said:

Thats interesting. Almost like the fact that I have a repeater frequency (radio channel 26) in the line of channels in between my channel 1 and my channel 31 that is interfering with my ability to TX on 31?

 

(thanks for considering my situation!)

as a workaround, I moved to the low powered GMRs/FRS channels in the 8-15 range since I use those less. I don’t have any custom repeaters sharing that channel. I’m having a hard time explaining it. 
 

last night I used CHIRP over a USB cable and tried a few things with duplex off and what have you before I moved to the FRS channel range that so mentioned in the previous paragraph. 
 

BTW, TIDRADIO has not replied to my request. I gave them the URL to this post. 

In GMRS MODE... channels 31-54 (I think) will automatically act like they are repeater duplexing channels... where they automatically transmit +5 from the receive frequency. Now, you can override that in chirp by setting the SPLIT instead of the + and entering the same transmit channel to make it a SIMPLEX.

Here are some screenshots of my CHIRP screens and how i set up a simplex channel in channel slot 36 for instance:

first one... shows how I am changing the + to SPLIT... (will be entering the same transmit frq as the receive freq to kindof bypass the repeater offset)
Second image you get a popup to enter the tranmit freq.. make it the sameas you receive.

thrid.. is is set... upload to radio.


note that if you SAVE your chirp files... if you re upload them again at some point wihtout touching the settings for those simplexx channals it might still show it when you reopen the file like it has reset to the + and offset but it will be ok when you put it back in your radio... IF HOWEVER you do make any edits to that line... you WILL have to redo this procecdure or it will think you want it to just do a repeater offset. 

hope that makes it clearer and it helps you get it working.





 

[LeoG]

CH31 is a repeater frequency which will transmit at 467.xxx frequency and receive on 462.xxx frequency.  You need to limit yourself to the lower 22 channels to stay in simplex, TX/RX on the same frequency..

[Imply4907]

Hi @TrikeRadio and @LeoG

I also observed the phenomenon at HT Channel 100, which is clearly outside of the 31-54 range that @TrikeRadio mentioned (he was guessing).

But I am going to re-read the posts as I just skimmed over them. I'm interested in the "skip" feature. When using Odmaster, that's not an option. In Odmaster, I use the same frequency for both TX and RX.

Has anyone been able to replicate my situation with his/her TD-H3?

 

Best regards,

Jim

[Imply4907]

Side question, what's the standard way to express when I mean a channel on my radio model vs. a channel within the band? Thanks in advance.

e.g. there are 22 GMRS channels in the GMRS band. My TIDRADIO model TD-H3 handheld transceiver (HT) radio has 199 channels (which varies from model to model)

[Imply4907]

5 hours ago, SteveShannon said:

About the only way is to reference both:  “I programmed GMRS channel 16 into slot 100 on my radio, but it won’t work without setting a CTCSS tone.”

That's pretty succinct, @SteveShannon. thanks

 

[SteveShannon]

1 minute ago, Imply4907 said:

That's pretty succinct, @SteveShannon. thanks

 

Instead of “work” I would say “transmit”, if that’s accurate. “Won’t work” doesn’t provide enough information. 

[Imply4907]

On 1/22/2025 at 3:41 PM, LeoG said:

CH31 is a repeater frequency which will transmit at 467.xxx frequency and receive on 462.xxx frequency.  You need to limit yourself to the lower 22 channels to stay in simplex, TX/RX on the same frequency..

Oh gosh! So I used CHIRP and it programmed the frequencies wrong on the radio! I figured I'd use CHIRP since it's a bit deeper. I attached pictures.

 

I read the radio, inserted a line at slot 22, copied slot 1 (GMRS ch. 1) to empty slot 22. Then I changed the name and added the tone. Wrote back to the radio (I didn't save the image). I noticed I could transmit on 22, but I also noticed that the frequencies didn't go in the way I programmed them.

I am on a pretty new version of CHIRP (not the bleeding edge) but not more than 2 weeks old.

[Imply4907]

I see people install alternate firmware on H3's. Maybe I should consider it? I don't know. I'm pretty new with these radios (not software and firmware, though).

[Imply4907]

2 hours ago, LeoG said:

I think the H3 has a limitation that you can only transmit on the 1st 54 programmable channels.  After 54 they are receive only.

@LeoG, that might have been the issue. I may have overlooked it in the owner’s manual about the transmit channel slot limitation. I will have to find it and confirm. But I was able to program GMRS 1 on slot 43 on the keypad with some CTCSS tones and it appeared to transmit. I’m out on the road and can’t test thoroughly. Thank you for the tip.

[RIPPER238]

9 hours ago, LeoG said:

I think the H3 has a limitation that you can only transmit on the 1st 54 programmable channels.  After 54 they are receive only.

I have no issues transmitting on higher channels. 185 for example, no issue. GMRS version unlocked. 

[LeoG]

Maybe they fixed it since version 702

[RIPPER238]

15 hours ago, LeoG said:

Maybe they fixed it since version 702

Limitation of the machine. lol

Maybe? Technically I transmitted on CH185 on ~2M. Haven't tried GMRS that high. 

[LeoG]

In GMRS mode using ODMaster I was not able to program a transmit frequency into the H3 with 460819 version.

[LeoG]

And using the APP from Tidradio I was also not able to program any transmit frequencies into channel 55, I assume and up even though I didn't try.

I have AM stationed programmed into the radio and the APP won't read those from memory either.  If I write back I lose my AM stations (Airport).

[LeoG]

Just upgraded to v250110 and still no joy on ch55 transmit