Kenwood DMR via Single Frequency Repeater

[SARRG]

Looking for a Single Frequency Repeater solution for Kenwood DMR portables (NX-3200's).

See both M and Hytera have them.

Does anyone have any experience with either using Kenwood DMR radios through the non Kenwood SFR ?

thanks
Peter

 

[mmckenna]

I've never seen Kenwood offer a single frequency repeater solution.

 

[kd4efm]

It think there is some confusion with your statement.
All DMR repeaters are single frequency. There is no such thing a dual frequency Dual slot. unless you're talking about a trunked DMR system.
where 1 slot is the CC, and slot 2 is a voice, plus x # of repeaters attached to it.
(No, kenwood wont do CAP+ or CAP MAX or any proprietary mode above tier 2 conventional, otherwise it's Tier 3 Trunked)


Kenwood is ETSI compliant for tier 2 (CONVERNTIONAL DMR 2 slot)
So, that being said, any basic dmr conventional repeater in dmr mode will work with the NX-series of dmr radios.

The only issues, XPR3500 and 4500 that have older firmware, will fight with Kenwood's when over the air alias is used.

the newer slr and whatever else is on the market (Tait, Hytera, Kairos, etc.) have no issues with Kenwood's at this point in time.

 

[mmckenna]

OK, yeah I may be confused. I know Hytera had a system for a while that would use a single frequency for TX and RX, it would listen on tone timeslot and transmit on the other, all on the same simplex frequency.

 

[otobmark]

I’ve played with an Anytone in single channel repeat to see if I could come up with a subscriber agnostic solution. My work around is to create 2 channels that are identical except for timeslot and put them in their own scan list. If radio A transmits on TS1, anytone repeats out on TS2 which radio B catches on scan (if TS2 TX then repeat TS1). The only downside if you want to call it that is if you are in simplex range of other radio it may receive you direct depending on which TS it hits first while scanning.
Anytone has an incestuous way of doing this with other Anytone radio on a single memory channel. Motorola has a way with their lunchbox fill in repeater which uses split CC. My goal was cross brand interop and it works.

 

[sallen07]

All DMR repeaters are single frequency.

OK now *I* am confused. Are you saying that they recieve and transmit on the same frequency, with no offset?

 

[SARRG]

I know Hytera had a system for a while that would use a single frequency for TX and RX, it would listen on tone timeslot and transmit on the other, all on the same simplex frequency.

This!

I have conventional DMR Tier II VHF repeaters that use two frequencies - standard repeater. I have a use case when repeater pairs may not be available or time to re-tune a duplexer and get it deployed slows a response. Would like to have a single frequency repeater (SFR) solution in those cases. There are a few videos on YouTube showing this being done with a Hytera portable as the SFR but with Hytera portables for the subscriber units. The Hytera MD-782i-FD with feature license has this capability. M is also selling a version of the SLR1000 with a "hi-speed" Tx/Rx switch and a feature license.

Having never used either and having a Kenwood conventional DMR system trying to find out if any Kenwood portable/mobile users have experience with either the M or Hytera SFR solution. Or any other. As mentioned, Kenwood does not, which is a shame as it would be a useful feature in the NXR-1700.

 

[otobmark]

My post must have been unclear. My solution does EXACTLY what you want. I used anytone mobile for SFR but any radio capable of repeating from one timeslot to another on same frequency could be repeater. All of my subscriber radios (moto, Kenwood, hytera, anytone) work with this solution. Haven’t tried my VP8000 which doesn’t do dual slot simplex so will probably not work. You do need a bidirectional repeat mode where the repeater can receive either TS and will output the other. TS1 to TS2 AND TS2 to TS1. I bought the anytone mobile just to test the idea and it worked. No experience with other radios which possibly could be limited to one direction.

 

[otobmark]

OK now *I* am confused. Are you saying that they recieve and transmit on the same frequency, with no offset?

Yes. They tx on 1 TS and rx on the other. The radio used as repeater rx TS 1 and repeats on TS2 (or vice versa). The repeater is alternating between listening on one TS and transmitting on the other TS.

 

[sallen07]

Yes. They tx on 1 TS and rx on the other. The radio used as repeater rx TS 1 and repeats on TS2 (or vice versa). The repeater is alternating between listening on one TS and transmitting on the other TS.

Thank you, but the question wasn't directed at you.

I understand how a single-frequency DMR repeater works. My question is to @kd4efm who stated "All DMR repeaters are single frequency."

I have one (Motorola) and it definitely uses an offset like an analog repeater.

 

[SARRG]

My post must have been unclear. My solution does EXACTLY what you want. I used anytone mobile for SFR but any radio capable of repeating from one timeslot to another on same frequency could be repeater. All of my subscriber radios (moto, Kenwood, hytera, anytone) work with this solution. Haven’t tried my VP8000 which doesn’t do dual slot simplex so will probably not work. You do need a bidirectional repeat mode where the repeater can receive either TS and will output the other. TS1 to TS2 AND TS2 to TS1. I bought the anytone mobile just to test the idea and it worked. No experience with other radios which possibly could be limited to one direction.

Thanks! This is good to know that it works with the usual suspect subscriber radios.

 

[otobmark]

Disclaimer: I’ve only tested close range and have no idea how sensitive the anytone is in single frequency repeat mode. Some deafness may occur.

 

[otobmark]

A standard for single frequency repeater operation would be ideal but probably won’t happen. My work around requires subscriber scanning two memories containing exact same simplex frequency and color code but different TS’s. I read the white paper on Motorola implementation and didn’t really understand it. It used different color codes on TX and RX and was capable of extending a regular repeater seamlessly—-this is where my understanding fell apart! The Hytera solution is probably the most usable but limited to their radios.

 

[SARRG]

Agree on the standard.

The Hytera solution is probably the most usable but limited to their radios.

From the video, it looked pretty slick. This is what I am trying to determine (and was worried about). Trying to find out if anyone has tried this specific pairing of Kenwood and Hytera (or Motorola). Thanks!

 

[dede1966]

Yes. They tx on 1 TS and rx on the other. The radio used as repeater rx TS 1 and repeats on TS2 (or vice versa). The repeater is alternating between listening on one TS and transmitting on the other TS

.So if i understand you guy's correctly, I setup my SFR to RX on TS1 and it will TX to TS2 that is ok, and in my XPR7550 i setup repeater TS1 with correct CC and it will RX on TS2 if that so no need to buy other radio.. Is this correct ??

 

[otobmark]

The XPR7550 is the wild card in that I'm not completely sure how it handles SFR. In Motorola white paper it uses SFR as a "fill in" repeater extender with a regular repeater system. Moto uses split tones and I'm not sure exactly how it all works or how flexible it is. I think it is based on the use of a specific fill in repeater device as opposed to a regular Moto repeater. It doesn't specifically do split memory.

What are you going to use for a SFR? They don't all work the same. I chose the Anytone because relatively cheap.

--Set up your SFR to receive on one time slot and transmit on the other. (can be uni-directional or bi-directional).

--On subscriber radio, set up 2 identical channels (memory positions) with the exception of time slot, one is TS1 and other TS2. Put the 2 channels (memory positions) into a 2 channel scan group (minimum or no hangtime). If the SFR is bidirectional then it doesn't matter which channel the subscriber TX's on. If SFR is unidirectional, then set up subscriber radio scan group to always TX on the correct channel (correct TS). As I said before, using this method you may receive another subscriber direct if it is in simplex range.

 

[dede1966]

The XPR7550 is the wild card in that I'm not completely sure how it handles SFR. In Motorola white paper it uses SFR as a "fill in" repeater extender with a regular repeater system. Moto uses split tones and I'm not sure exactly how it all works or how flexible it is. I think it is based on the use of a specific fill in repeater device as opposed to a regular Moto repeater. It doesn't specifically do split memory.

What are you going to use for a SFR? They don't all work the same. I chose the Anytone because relatively cheap.

--Set up your SFR to receive on one time slot and transmit on the other. (can be uni-directional or bi-directional).

--On subscriber radio, set up 2 identical channels (memory positions) with the exception of time slot, one is TS1 and other TS2. Put the 2 channels (memory positions) into a 2 channel scan group (minimum or no hangtime). If the SFR is bidirectional then it doesn't matter which channel the subscriber TX's on. If SFR is unidirectional, then set up subscriber radio scan group to always TX on the correct channel (correct TS). As I said before, using this method you may receive another subscriber direct if it is in simplex range.

I am trying to maximize our equipement, we are a sporting event EMS team and sometime we are out reach of the repeater and no cell service, i am exploring way's to expand coverage, we have DMR and NXDN radio in UHF , maybe a mobile repeater with a 50 foot pole... any sugestion?

 

[mmckenna]

I am trying to maximize our equipement, we are a sporting event EMS team and sometime we are out reach of the repeater and no cell service, i am exploring way's to expand coverage, we have DMR and NXDN radio in UHF , maybe a mobile repeater with a 50 foot pole... any sugestion?

What is your organization like? Is it private/business or are you part of a city/county/regional/state agency?

If you are an agency, there are plenty of UHF repeater pairs in the interop pool, plus the UHF Med channels that you would qualify for. Contacting your Statewide Interoperability Coordinator at your State OES (or whatever they call it in your state) would be a good place to start.
If you are a private group, then an itinerant UHF repeater pair would be easy enough to do and give you the ability to set up in different locations.

Lots of small suitable repeaters out there. I've got a couple of Kenwood NXR-1800 UHF repeaters I'm about to deploy at one of our remote sites. They'll do analog, NXDN or DMR as well as mixed mode.

 

[AF1UD]

Quick side note, do the NX-5K series support DCDM?

 

[mmckenna]

They will do Dual Slot, Direct Mode.