Digital Multimode Reflectors

 I am more interested in the Reflectors for DMR & P25,  most are centered around D-Star, here are some :

XLX

XRF

P25ref by G4KLX

NXDNref by G4KLX

alternative P25ref by DG9VH

alternative P25ref by M0VUB

code bases are found on GitHub

P25 Activity as of August 2024

 here is a bit of a list of known and active P25 TalkGroups  primarily from a VK/ZL perspective, but includes the main Overseas TG's and their dashboards (where applicable)

TG4 - VK4TUX  is defunct, long gone.

TG445  SuperMag AU - p25.supermag.fishersaudio.com.au  - defunct, its gone

TG530  ZL (NZ)   - zldigitialreflectord.hopto.org  - defunct, its gone

TG5057  VK7HSE  45.248.50.37  XLX505  dashboard is there, but no P25 port anymore

TG5205 CCARC VK2RAG  5205.p25dvm.com  - not configured

TG10100 World Wide  - is active

TG10101 TAC1 - no activity seen

TG10102 TAC2 -no activity seen

TG10201 USA -is active, but not that busy

TG10202 USA - no activity seen

TG10400  VK - pacificp25.repeaters.info  -  is active

TG10401 VK WICEN - pacifictac1.repeaters.info  and p25wicen.repeaters.info  - activity is scarce

TG10403  Pacific TAC3  - China stations

TG10403  Pacific TAC4  - Taiwan

TG10700  AU - active, but dashboard has gone

TG10750  AU Secondary  - defunct, its gone.

TG50525  VK Bridge  50525.p25dvm.com and tg505.repeaters.info  - very active, linked to VK3network

TG50535  VK Multimode  Link    p25to50535.vkradio.com   -  defunct, its gone

TG50536 FreeStar VK  p25.tg5036.vkradio.com    defunct, its gone

TG53099  ZL Bridge  (NZ)  203.86.206.49  (XLX750)  operational, but no P25 port anymore

 

here are some Nets to listen to on DMR in VK/ZL, as of 13th May 2024

VK3XEM's Welfare Net, Mon to Fri 10am AEST, runs on the VK3 AllStar Network, but accessible from Brandmeister DMR TG 50525, also P25 TG 50525 and I think also on NXDN TG50525.

VK3KK Round Table Net, Wed 8pm AEST, same network as above, on the VK3 AllStar Network, but accessible from Brandmeister DMR TG 50525, also P25 TG 50525 and I think also on NXDN TG50525.

ZL Digital Net, Friday night, 8pm NZT, 6pm AEST, on  VKDMR TG 530 ZL Call Freq

Westlakes  Net, VK2ATZ  Sunday morning from 8.00am AEST on VKDMR TG3802 linked to Brandmeister TG5052

Westlakes Broadcast, Sunday morning 9.00am AEST on VKDMR TG3802 linked to Brandmeister TG5052

VK7 WIA / REAST Broadcast, Sunday morning 9.30am AEST on VKDMR TG5

VK-DMR Net, Tuesdays 0900z on VK-DMR TG505

BMARC Monday night net 19.30pm AEST and Thurs 19.30pm AEST via Brandmeister TG50520

 Port Stephens Net Thurs nights 19.30pm AEST VK-DMR TG3809 & Brandmeister TG5109

DMR Node count for VK & ZL

 I have taken stat count of nodes in the past, this time I have written it down, but a couple years ago,  I found the numbers were much the same for VK-DMR versus Brandmeister nodes, in terms of VK activity, what I recall was around the 240-250 mark and looks much the same again today.

here is the count as of today, 22nd April 2024 for VK and ZL

VK-DMR :  Hotspots 242, Repeaters 56, Total=298.

BM  (VK): Hotspots  269, Repeaters 11, Total=280

ZL DMR+ : Hotspots Total=55 

BM (ZL): Hotspots Total=32

NOTE in ZL, repeaters don't have distinctive callsigns like VK does.

This is not a comparison of what is best, each type of DMR network does a different job, they are configured and operate differently, it is all about experimenting and learning, regardless of using one or both DMR modes and same goes for experimenting with other digital modes within the hobby.

another DMR network

 

I discovered there is another DMR network out there,  this one called FreeDMR, looks to be based out of the UK. It has talkgroups for Australia 505 and 5050  and for New Zealand  it has TG530. It is aimed at opensource development and experimentation.

FreeDMR – Open Networking. Reaching out to the World.

Invalid radioID with dmr and p25

 Here is a news item excerpt  from the Brandmeister.network webpages,  this is important as I have also seen a few VK callsigns running invalid RadioID's  on the BM network. As the message states, you need to register and obtain a  valid RadioID number from RadioID.net that matches your callsign, otherwise the network administrators will block you.

DMR status updates as of 3rd January 2023

Status update on changes for VK-DMR and Brand Meister networks  for VK (Australia) region.

Using DMR – VK DMR this is link to VK-DMR Supported TalkGroup listing.

 Note : VK-DMR is still gatewayed to Brandmeister equivalent TG's

VK-DMR  TG's 3801, 3802, 3803, 3804, 3805 & 3807 all on TS2  gateway respectively to

Brandmeister TG's 5051, 5052, 5053, 5054, 5055 & 5057 as respective State TG assignments

IPSC2 Dashboard Index (vkdmr.com)  VK-DMR Repeater dashboard, currently 57 repeaters connected.

IPSC2 Dashboard Index (vkdmr.com) VK-DMR Hotspot dashboard, currently 268 hotspots connected.

Note: VK-DMR now has some gateways into the Fusion Repeater network.

Repeaters | BrandMeister Brandmeister Repeater dashboard, currently only 11 licensed repeaters in VK, being VK2RAY, VK2RCM, VK3RAH, VK3RBA, VK3RHD, VK3RSV, VK3RUT, VK4RDB, VK6RDM, VK6RLM &  VK7RCR

Hotspots | BrandMeister Brandmeister Hotspots dashboard, currently 252 hotspots connected.

LastHeard | BrandMeister Brandmeister dashboard  "Last Heard" list of user activity.

BrandMeister Talkgroup List - pistar.uk this provides the full list of Brandmeister TG's worldwide, for VK refer to 505x and 505xx TG's

That was interesting comparing VK-DMR versus Brandmeister devices in VK (Australia)

57 x VK-DMR repeaters, compared to 11x Brandmeister Repeaters, 

whereas hotspots is pretty similiar with 268 on VK-DMR compared to 252 on Brandmeister.

Keeping in mind the structure and usage is quite different between VK-DMR and Brandmeister  networks. Each network serves a different purpose, don't try and compare one as being better than the other.

VK-DMR is repeater oriented, linking groups of repeaters in various combinations, but with no PTP TG's, whereas Brandmeister is not repeater focused, but has individual repeaters, but primarily is supportive of PTP connections and multi-mode gateways, including digital to analogue.

Digital mode hotspots and bad choice of operating frequency

 I was having a look at the VK-DMR and Brandmeister network dashboards today, seeing what new repeaters are active and what hotspots are running to gauge usage on DMR (as it seems rather quiet lately) and I noticed again, that there are still plenty of STUPID people running their digital hotspots on the most inappropriate frequencies, I have trouble trying to fathom how people with "supposedly" technical background and license (ham radio license) can make such stupid blunders, with 20MHz bandwidth to play with on the 70cm band, that they can't find a simplex without interferring with other services, especially the amateur satellite segment on 70cm, why would someone setup their hotspot in the amateur satellite segment when there are lots of amateur satellites constantly circling the globe operating across many frequencies ? People can't seem to grasp that you don't need lots of watts to work a satellite travelling overhead. That's why you can work ISS with a small handheld. Your little hotspot running milliwatts can interfere with amateur satellites passing overhead.

Likewise, why would someone setup their hotspot on the same frequency as the input of a analogue voice rptr that's less than 100km away ? Same for the output frequency.  The hotspot may only run milliwatts, but given some enhanced propagation, that tiny signal can go a long way.  I run three hotspots, for P25, VK-DMR and BM and I try to run them with as minimal impact on each other and maximum isolation between each hotspot and other services, i.e. power output turned down and use internal antennas, I was surprised how far away I can hear my hotspots when out walking with my P25 and DMR handhelds, a couple milliwatts, cct bd antenna and located downstairs in the garage and I can hear them almost a kilometre away. Weak signal experimenters will agree, small signals can go a long way under the right conditions.

If you see a friend operating a hotspot on an inappropriate frequency, can you politely ask them to think about a more appropriate simplex. Also if you running a low pwr hotspot you don't need a repeater frequency pair. Repeater frequency pairs are for high powered repeaters providing a large coverage area and as such, are licensed as repeaters. And if you running a hotspot whilst mobile all over the countryside, the choice of frequency for your hotspot is more important it needs to be on a simplex frequency, not on the allocated voice repeater allocations.

Improving receiver performance for Pi-Star MMDVM hotspots

 Since on the subject of my Pi-Star MMDVM hotspots, here is a tip for improving  the receiver performance if you running multiple hotspots of even a single hotspot in a high RF  environment.

Remember these MMDVM hotspots and even the other hotspots like OpenSpot have a simple wide-band receiver which can be easily overloaded, one thing I noticed when running my MMDVM in P25 mode was that  I was getting a lot of artifacts on my transmissions from my Motorola handheld when I operated in the same room or nearby rooms to my hotspot, it was much better when I operated from outside my house or other end of the house. First I thought don't use the little attached external antenna, but even when using just the onboard cct board antenna I could still overload the receiver up close  and I also noticed that when my DMR hotspot was transmitting I was getting errors on P25 receiver, even though the two hotspots operate almost 20MHz apart, I had all my hotpots running off the same USB power adaptor and I could get different behaviour by moving them around.

I decided to try some ferrite core clipons on the USB cables,  this was because I realised I could hear the USB power adapter noise getting into my HF receiver and it varied as I moved the hotspot position around, so I added some big clip-on ferrite cores and wrapped the USB cable through the hole a few times and experimented for best and minimum  effect on HF, I cleaned up all the noise. I was not quite sure who was the main culprit, so I added the multi-turned ferrite end of the cable closest to the hotspot. 

Later and purely by accident,  I was playing on P25 and noticed I not getting the errors I was previously getting, as normally I could not run my Motorola handheld in close proximity without getting artifacts on my transmissions, I also noticed the DMR hotspot now not de-sensing the P25 hotspot. This proved the hotspot receiver was picking up RF via the USB power connector, from this I made sure all my hotspots had a either toroid or big chunky ferrite clipon (14mm ID) with several turns of USB cable and fitted as close to the hotspot power connector as possible,  Now I can operate ether either DMR handheld or P25 handheld in reasonably close proximity to the hotspot without interfering (desensing)  with the reception of opposing hotspots. I also added smaller 3.5mm clipon ferrites at the power adaptor end of the USB cables.

It was a win-win situation, I reduced noise affecting my HF receiver radiating from hotspots and USB power adaptor and improvement of receiver performance of my hotspots by reducing receiver desense from other hotspots RF entering via USB power cables and localised RF from handheld transceivers. In terms of the MMDVM boards, if operating in a high RF environment, you are better not to use the external antenna, just use the on-board cct antenna. Only use the external antenna if operating out on low noise floor environment like a farm. Also if you running multiple hotspots, try to separate them from each other, the further the better, remember even with mW transmissions, the signals are still flattening each other's receiver front end at close proximity.

PiStar for MMDVM Release 4.1.3 and 4.1.4 now available

 I noticed this morning on my PiStar MMDVM Dashboard consoles,  that it was showing an alert message at the top of the PiStar (red) Dashboard page,  advising me there was a new release and that I simply need to click the link to upgrade my two PiStars, one was 4.1.1, the other was 4.1.2.

Clicked the link, it upgraded within  30 seconds or so,  and it ready to go, first my SingleHAT MMDVM went from 4.1.1  to 4.1.2, then clicked the link again from Admin  console view to upgrade it to 4.1.3, then the Alert appeared  again, I then clicked again to go to 4.1.4,  I then followed same procedure to do my  DualHAT MMDVM node, going from 4.1.2 > 4.1.3 > 4.1.4

This was so easy, OMG, that simplification of upgrade by the PiStar Development team was absolutely fantastic.  The manual method of upgrade did not phase me, but I did wonder how non-computer related people would do the upgrades.  But the answer to that dilemma is now right there in the latest dashboard.

Congratulations to the PiStar Development Team for the new automated upgrade process.

As of today, my MMDVM nodes have PiStar 4.1.4  and Dashboard  20210203  (3rdFeb2021)

PiStar Downloads and Releases