Kirisun DR550 dPMR Repeater

[paulears]

Has anyone had any experience of these repeaters? I can't find any proper information or a manual for them, so can't see if they'd meet the requirements for a job in the future I have in mind. I've only just started with dPMR for business users, with my existing digital experience coming from DMR. So far, DMR is proving a little unfriendly with other radio and audio systems in close proximity - the pulsing of the hand-helds when close to audio kit that doesn't like string RF is quite obvious. The single 'pop' as analogue and dPMR radios have the PTT pressed is more livable with. I've no need for any commonality - the systems are stand-alone, so dPMR is doing the job. I've some bigger events coming up, and a repeater seems sensible as the coverage area required is a little bigger.

These Kirisun repeaters seem very common in advertising, but apart from one useless youtube video of somebody switching one on, in a foreign language, nobody seems to be talking about them at all - and Kirisun haven't responded to my enquiries. Ideally, I'd like to have a look at the programming software as that's likely to explain more than a badly translated manual.

[radiosification]

In my experience, the Kirisun dPMR handhelds are very poor in terms of RF performance. I personally wouldn't go near any of their dPMR stuff for anything serious. You could go with some Icom or Kenwood dPMR radios instead, and those two brands of dPMR radios will work together when programmed correctly to do so, so you can buy a mix of them if you wanted to. Then you'll also be able to work on NXDN trunking networks or repeaters too, which is handy. NXDN trunking seems very good to me.

I don't think the Kirisun handhelds have any sort of AGC, so the voice is a bit like analogue on them - some people come through stupidly quiet and others really loud. Except they can do it even worse on digital and still get through, because if they did that on analogue they'd be under the noise floor a lot of the time. They aren't really the right type of radios to give to people who aren't radio enthusiasts.

I can't comment on the repeaters but I think they are just two mobile radios linked together.

[paulears]

Ha! my experience is just the opposite - I'm mixing the Kirisun S760 with the Anysecu dPMRs and between S760s -S760 and S760 to Anysecu, the audio quality was what swung it. Sounds better to me. I did pretty comprehensive testing and also can't find any issues with RF performance, and on analogue, the filtering (probably as a result of the FDMA narrow band requirements) seems to work better with strong off channel signals present. Selectivity seems better. Sensitivity is slightly lower, but that's not a deal clincher. DMR I can see being sensible for amateur use, but holding the 380 in one hand and the S760 in the other, I'm going with dPMR for the business radio. The small, Baofeng 888 sized Anysecu is very cheap for a non-screen digital radio, and they're a perfect partner for the Kirisun. There isn't, as far as I'm aware a DMR cheap that does the same thing.

I'm fairly certain the repeater is not two radios in one box as the duty cycle seems 100% and the feature set and buttons on the panel don't seem to match? I'll have to wait and hope Kirisun come back to me. I did toy with the kenwoods, but the price is a bit hefty - but I've had decent experience of their kit. I've no real need of trunking - practically all my work would be in very local areas.

Have you had problems with your Kirisun equipment? You've not mentioned it before? The kenwood portable could be useful - but again, it's down to cost. The project in planning will probably be 6 to 10 hand held and a repeater - very simple stuff, but not the most careful of staff using them. They break the analogue regularly, so replacement costs are important, as they're going through so many. Currently on Motorolas, but being dropped from 15m onto hard surfaces is common. They're tough, but still break when abused.

[radiosification]

Oh that's interesting. Yeah I had problems with my pair of S780s. They had awful RF performance. Maybe Kirisun have improved the radios since then. Also one of them broke. I turned the volume up to full and it just totally stopped working. I had to send it back to china. They sent me a new one.

I was comparing them to Motorola DP3000 series at the time, and the RF performance wasn't even half as good. They cut off when I did a range test when analogue was still very clear. I just couldn't understand it. The DP770, a DMR radio by Kirisun, was a heck of a lot better than their dPMR stuff at the time. It was even waterproof, which I tested. Not quite as quick to recover as the motorolas but it survived being immersed in my sink full of water.

I may just be remembering incorrectly about the repeater so don't take my word for it! It was quite a while ago that I remember seeing that. Probably about 2 years ago now.

I've always thought that the Motorola DMR equipment, particularly the DP3000 series was incredibly tough. I've seen builders carrying around DP3400s that look like they've been dragged through the middle of a mountain of rubble!

With regards to audio quality, I actually prefer the AMBE vocoder to the ASELP vocoder used in the kirisun. I think the ASELP is a bit better for treble response, but on the other hand I think that the AMBE vocoder sounds slightly more natural. Although I haven't used it in any other radios than the S780 so again it could just be that. ACELP would be a dream, but that's only used in TETRA stuff for some reason. If someone made a dPMR radio with the ACELP vocoder in I'd buy it straight away.

I have videos of a lot of this stuff I've mentioned here on my YouTube channel so if any of it interests you, there is more info on there.

[paulears]

Thanks - I'm trying to put together a common testing rig. I'm thinking about a transducer like they use in hearing tests, that can be physically attached to the radio, and then I could replay a consistent test message with voice, pink noise and perhaps tones, then I should be able to do a comparison on what is received the other end of a link - same model to model and to different models. That way the filtering of the frequency response could be measured rather than just random one two, one two test which is what most people do for their 'tests'. It would also reveal the latency differences (if there are any). I'm not remotely excited about the different codecs they're using, just the quality of output. Initial thoughts suggest they just sound different, I'd like to see if there's a trend? For example, the S760 analogue audio is lower in level end-to end than digital - suggesting it isn't a mic problem. The 380 has pretty much the same level on analogue and digital.

The supplier got back to me and I now have a Kirisun DMR and dPMR repeater manual. The dPMR is much less complicated. The DMR has IP settings for connection to other units to increase coverage by linking, and more tweakable parameters. One disadvantage seems to be that although they can autoswitch between digital and analogue on the same frequency, they only have a single CTCSS frequency, so no good for multiple users, although the DMR 'suggests' that multiple colour code groups can be passed, the dPMR makes no mention of this feature - so still unclear. The manual for the dPMR is brief in the extreme, with practically no operational info - just buttons, sizes and RF specs. Both have space for a duplexer, which is handy. Worst bit though by far is the weight. Both have steel cases and are 4U tall, making shipping damn expensive.

[radiosification]

Well good luck with that. I haven't got much else to comment really. Let us know how it goes, and if the dPMR repeater is any good or not.

[zippy]

I guess a lot also comes down to the handsets used, you can have the best repeater money can buy but it still conforms to the 'rubbish in rubbish out' policy.
being a bit dim I managed to buy a dPMR set instead of a DMR set, I can't tell you if it was any good as I never hear anyone on the thing except in analogue mode which was pretty similar to my uv-5r cheapo set.

[paulears]

If you want to get shot of it, I might be interested. I've actually got some info from Kirisun now - and the DMR repeaters have built in interfacing via IP, while the dPMR one has an accessory socket, but the dPMR one doesn't. So again, DMR seems to have more wide area capability with linking, while dPMR is simply a digital replacement for analogue?