9cm microwave band Test Beacon from VK1

 

Dimitrios Tsifakis via groups.io <dtsifakis=gmail.com@groups.io>	Jun 14, 2026, 11:12 AM
to VK-Microwave

Hi all,

This beacon is mainly of interest to the ACT members.

The 9 cm beacon is finally on air! The nominal frequency is 3398.8 MHz, the beacon power output was measured to be +15 dBm past the final filter. Out of this power I expect about +10 dBm to make it to the HPOL antenna. The beacon transmits 12 WPM morse code that includes the callsign (VK1SV/B) and the approximate location (QF44).

Its stability should be superior to previous beacons I have put on air, however there might be a small offset from the nominal 3398.8 MHz operating frequency. Using an (uncalibrated) SDR, I see it at 3398.80045 MHz (450 Hz higher than the nominal freq). YMMV.

This may be a beacon that can only be heard from mountaintops, but in any case, reception reports, positive or negative, are always welcome.

73, Dimitris

PS, I have obtained a 10 W 3.4 GHz amplifier from aliexpress but haven't powered it up yet. It cost me about $40 from memory. This could be used to bring the beacon to a watt or so of output power in the future. A discussion including some measured data about this amplifier can be found here: https://www.eevblog.com/forum/rf-microwave/10w-rf-amplifier-3400-3800-mhz-from-aliexpress-reverse-engineering/

VK2XB- Indy - truck mobile missing from APRS

 When I occasionally  look around on APRS, I often spot Indy VK2XB mobile somewhere in his big rig (semi-trailer truck), but I havent had time to look around for past 6months, except for my own travelling between new home  in Yass Valley and back to Sydney and have been doing that each week for a few months.

Anyway, back to VK2XB,  I had a look on APRS to see where he travelling and I noticed he hasnt been on APRS since January. I thought, oh I hope nothing bad happened. I did some searches and spotted an article in March on Brisbane Radio Society but not much else. 

VK-DMR Network Loop example

 Here is example of a 'network loop' within the VK-DMR Network,  you can see one hotspot latching onto any nodes that have their Node defined as Public instead of Private, you can see this in the Pi-Star configuration when setting up DMR mode. Unfortunately I was rebuilding my MMVDM node with latest Pi-Star image and it so happens the Public vs Private settings was set to default of Public, hence my node latched on VK3MJR's hotspot and would not let go, even though I then changed my Node to Private, so it was too late, its stuck.

From the VK DMR hotspot dashboard I could see where my node suddenly was, along with several other people's hotspot. All I can do is power down the hotspot for some time and hopefully it will get released by VK3MJR's node. Will see if I can contact owner and get him to fix his hotspot configuration.

Sunday 6metre FM Nets

 Whilst listening  to the Westlakes ARC Net and broadcast on VK-DMR TG3802 talkgroup starting at 8.30am local and broadcast starting at 9am local, the callback mentioned the 6metre net starting  at 10am which it did, as I could hear it on the VK2RSN repeater 53.625 MHz

Then tonight I heard the Blue Mountain ARC 6metre start at 8pm on VK2RBM repeater 53.875 MHz 

Good to see some groups making good use of 6metre repeaters

Linux Mint upgraded to 22.3

 recently I did the upgrade of my old ASUS laptop from Linux Mint 22.2 to 22.3 successfully.
The upgrade tools get easier to use each time.
As I said in the past, if you got an old PC or Laptop that is too old and slow for MS Windows, then recycle it and install a flavour of Linux on it for a new fast, lease of life.

Interference across 6metre band in Frenchs Forest area,

 Interference across 6metre band in Frenchs Forest, NSW area

Over last couple months the interference has become worse across 6metre band, more noticeable, whilst scanning the 6metre FM repeater segment, I did a sweep from 46-60 Mhz  and found there is wide band signal covering 52.500 to 57 MHz, the signal strength varies from s5 to s9 across that segment.
I suspect it radiating from Northern Beaches Hospital, possibly some piece of medical scanning equipment.
If scan across  the band with a narrow band receiver, it just seems like white noise, but the signal strength meter shows there is something there. 

This happened a few years ago and I tracked it to the hospital.and suddenly it went away.

UPDATE: 19 Feb 2026
I spent some time doing  better sweep, due to hearing some sort of buzz sound opening the mute on a repeater output frequency. Superimposed on that buzz sound is a click at approximately 1 per second rate, noted in the morning, afternoon and night at times when I checked. I swept from 46 to 60 MHz, these are the frequencies I noted the buzz sound on.
 these following frequencies were weak s0 but clearly audible :
50.030  50.060 51.280 51.870 52.140
these following frequencies were strong ie. s5 to s9 :
52.440  53.080  53.640  53.690  54.240  54.280  54.840  55.500  56.050  56.090
these following frequencies were weak s0 but clearly audible :
57.270  57.310  57.900  58.470  59.110  59.680  59.720

Overall, the raised S-meter was from 52.500 to 57 MHz,  where as the narrow bandwidth buzz sound is heard from  50MHz to 60MHz

23cm activity from VK3 this morning 26th January, 2026

 The VK3's having a cracker of a morning on 23cm SSB

Canberra Region and Wagga Region repeaters

 I was just checking out the repeaters for Goulburn and Southern Highlands ARC (GaSHARC) recently, as they have an extensive repeater network  from Yass - Goulburn - High Range, which led me to check out the Canberra and Wagga club's repeaters as we visit Canberra and Junee and also Tumut from time to time.

Both CRARC and WARC  have their own extensive repeater networks which are outlined on their respective websites.

Next time I out Junee way, I'll get to try out the WARC 6metre repeater VK2RBE,
I also noted CRARC still showing their 6metre repeater for Mt.Ginini as planned, so fingers crossed it that it gets finished and commissioned one day

Repeaters - Wagga Amateur Radio Club

Repeaters – CRARC

6metre repeater status in and around Sydney and NSW that I know of, as of 25th January, 2026

  6metre repeater status in and around Sydney and NSW that I know of, as of 25th January, 2026,

53.625 VK2RSN, Mt.Sugarloaf, Newcastle, operational, requires 91.5Hz tone

53.650  VK2RMP, Maddens Plain, Illawarra,  operational, requires 123Hz tone

53.675  VK2RMB, Terrey Hills, off-air

53.700  VK2RGN, Goulburn, off-air

53.725  VK2RAG, Somersby, Central Coast, operational, requires 91.5Hz tone, linked to 23cm rptr

53.800  VK2RCN, Port Macquarie operational

53.825  VK2RBE, Bethungra operational

53.850  VK2RWI, Dural, operational

53.875  VK2RBM, Blue Mtns, operational, requires 91.5Hz tone

52.525  FM Simplex - still plenty activity, particularly Sunday morning after ARNSW broadcast from Dural

P25 TG10700 Activity as of 19th Jan 2026

 P25 TG10700 Activity as of 19th Jan 2026