How can I make my repeater allow APPROVED unit IDs only?

[WRYF747]

Even though I don't have one yet, I'd like to know how to make my repeater only allow approved IDs through. And I'm not talking about MDC either.

Some GMRS and Ham Radios allow for the use of dial tones and unit IDs to access repeaters, and I want to make a repeater for only approved users. This repeater is just for property use only. I don't want the chance of someone finding a way to access the repeater and interrupting our communications, especially when events are in place.

[OffRoaderX]

I am not aware of any repeaters that do this, but the functionality may exist (others can chime in) but even if using a Unit-ID (ANI/DTMF), anyone could very easy spoof it and use the repeater..

There is no way that I am aware of on GMRS, without breaking the GMRS rules, to fully prevent people from using a GMRS repeater.

[gortex2]

It depends on the subscribers and the radios. a CCR radio wont do what you want. Motorola supports RAC (Repeater Access Control) but that's a form of MDC. There are not many options for analog options. I also use DCS for input and CTCSS on output. This helps eliminate many users but isn't a fail safe. 

[JohnE]

Another option would be using an LTR controller ,w/that said all of your radios would have to be LTR capable 

[WRKC935]

Motorola does have RAC for analog, but it's can be scanned.

A better option is to spend the money and get a part 90 license then you have better options.  First is you can run DMR (MOTOTRBO) and run a digital RAC and run basic encryption.  It would also allow you TWO talk paths on the same frequency.  Something that's no possible with analog radio. 

And the other thing with a part 90 commercial license is if others come in, outside of your family unit, they can use the license under your authority.  You can 't grant a non-family member access if they don't have a GMRS license.. so day workers and laborers that are not family can't use the radios. 

The basic encryption will also keep your radio traffic semi-private.  The 6 digit numeric RAC code will keep all but the most determined off the repeater.  And it really sounds like it would be a better option for your specific application. 

The issue is that you are so limited with analog radio.  And there is a greater limitation with the lack of encryption due to the regulations of GMRS.

I know that someone brought up using a trunking controller that would look at radio ID's to grant or deny access to the system, but there again, I don't know the regulations specifically for GMRS would allow that.  Would it work, sort of, until someone with a scanner that could display the LTR data was used to pick apart the information and then it's going to be screwed with if you are really expecting issues with others trying to gain access. 

I wouldn't typically go to these length's but you seem adamant in you post about it to the point you foresee issues before you even have equipment on the air.  And in truth, if you haven't bought any equipment for this yet, now is the time to look at other options that better match your listed requirements.

Personally, I am a P25 and AES encryption guy all the way.  That will always work and NO ONE gets to listen in.  But none of that fits within the rules governing GMRS.

 

[Lscott]

9 hours ago, WRKC935 said:

I know that someone brought up using a trunking controller that would look at radio ID's

I'm on another forum where somebody asked about getting the frequencies used on an NXDN trunking system from just the radio handset. They wanted the frequencies used just to scan. One poster said that's impossible without access to the system key file, available only from the trunking system admin. It just so happened one used radio I purchased came programed from a trunking system. The normal radio software won't read it without the key file. Well, I had a hacked version of the software that allows me to read the radio and save the info as a service file. I posted screen shots of the frequency lists etc. just to make a point that nothing is hack proof or secure as you would assume as far as the trunking info goes.

[Sshannon]

On 12/30/2023 at 2:02 PM, WRYF747 said:

I don't want the chance of someone finding a way to access the repeater and interrupting our communications, especially when events are in place.

Even if they cannot access your repeater, someone on the same frequency will disrupt your communications if their signal is stronger than others.

[WRYF747]

I decided to get a couple of Kenwoods off from eBay and use FleetSync.

[Blaise]

On 12/30/2023 at 4:02 PM, WRYF747 said:

events are in place

Nothing foreboding about that sentence AT ALL....

[gortex2]

53 minutes ago, WRYF747 said:

I decided to get a couple of Kenwoods off from eBay and use FleetSync.

So Kenwoods version of MDC.....

[OffRoaderX]

2 minutes ago, gortex2 said:

So Kenwoods version of MDC.....

..I was going to say the same thing, but when i say it 'some people' get butthurt.

 

[WRXB215]

36 minutes ago, OffRoaderX said:

but when i say it 'some people' get butthurt

I was going to say "that's the whole purpose" but 'some people' might... oh never mind. 

[tweiss3]

15 hours ago, gortex2 said:

So Kenwoods version of MDC.....

Which they seem to have abandoned on the VP8000. 

 

Other than the Quantar/Quantro having built in MDC decode, any other hardware or external controllers that are currently in production that can handle MDC? I was looking just to point of researching it, and haven't found anything.

[gortex2]

Im not sure if any aftermarket controller supports it. Back in the day Trident was playing with it but went to Passport instead. Personally I found RAS to be great to eliminate the CCR world on my stuff but it does limit the subscriber I can use with the system. For a closed repeater its not a huge deal. 

[Hoppyjr]

Maybe I’m slow, but if you chose a less used tone and don’t publish it, potential unauthorized users would have to try each possible tone combination to get access.

[OffRoaderX]

10 minutes ago, WRUZ229 said:

Maybe I’m slow, but if you chose a less used tone and don’t publish it, potential unauthorized users would have to try each possible tone combination to get access.

Not just slow, but also incorrect.

It is trivial to scan the input tone of a repeater as long as someone nearby is using it.

[WRYZ926]

"Privacy tones" are anything BUT private. As others have said, it is real easy to scan for the input and output tones of repeaters while they are in use.

[WRXB215]

2 hours ago, WRYZ926 said:

"Privacy tones" are anything BUT private.

True, "don't interrupt me tones" is more accurate but longer. 

[Guest]

1 hour ago, WRXB215 said:

True, "don't interrupt me tones" is more accurate but longer. 

... and a lousy marketing pitch !!!