update on 23cm Repeaters as of 5th December, 2022

 a recap on 23cm repeater systems centered around Sydney as of  5th December, 2022

Here are the operational 23cm FM Analogue repeaters I can work:

OUTPUT / INPUT    CALL          Location

1273.100 / 1293.100 VK2RTZ  Mt. Sugarloaf  - working,  it idents every hour, requires 91.5Hz ctcss

1273.200 / 1293.200 VK2RWC   Chatswood  - working

1273.400 / 1293.400 VK2RAG  Somersby - working, has beep on the tail

1273.500 / 1293.500 VK2RWI Dural  -  yes, it is working again.

1296.850  VK2RMP FM Simplex analogue parrot repeater at Maddens Plains - working, it idents regularly with a CW message

There is also some wide band or frequency  hopping digital signal that comes up occasionally, can be any time of the day, however, it only runs for approximately 30mins, then disappears,  it seems to come from direction of the city,  I won't call it interference, as it maybe a legitimate user of 23cm, as we are secondary users. It just annoying when you scanning. I see this signal down at 1250 MHz and all way up to 1296MHz, sometimes it will keyup Chatswood rptr and also keyup the Maddens Plains parrot rptr. 

1294.000 FM Simplex, not heard anyone since July 2022.

There are other known 23cm Repeaters, i.e VK2RRR Razorback and  others at Blue Mtns, Walcha, Muswellbrook, Lismore and Jervis bay,  all these have been unfortunately been cancelled, scrapped or never completed.

IARS 23cm simplex repeater update

  IARS 23cm Active beacon information and instructions

The Illawarra Amateur Radio Society Inc. (IARS)
is pleased to announce the testing of a Simplex Repeater operating on the 23cm band.
What
- FM Simplex Repeater operating on 1296.850MHz
- RF Power 25 Watts.
- Vertical Omnidirectional Antenna of 11dB gain.
- Input stage has a LNA with approximately +10dB Gain
Where
- Maddens Plains, Grid Reference QF55LR.
- Latitude: 34.27Deg South Longitude: 150.94Deg East
- Height: 371 Metres above sea level. (Not including the height of the tower).
Purpose
The purpose for the development of this particular repeater is;
To encourage interest and experimental development in the higher bands such as 23cm.
It can be used to assist amateur radio operators to develop their own station transmitters, receivers, RF amplifiers, pre-amplifiers and antenna design.
Test the operators experimenting with various modes.
It is a beacon which can be used to monitor propagation on the 23cm band.
Basic Description
The general principle of the repeater is that it is simple.
The transmitter stages consist of a 2 Metre exciter, followed by a transverter.
The transverter has an IF input of 144.850 MHz, up to, but no greater than 1.0W or else it may be over driven. The RF output is of the order of 2.0W. The next stage is the RF PA of 25W.
The memory of the controller chip has been programmed to function for a period of 150 seconds (2 ½  minutes) more than ample time to conduct any form of experimental test.
The antenna is a vertical omnidirectional antenna with approximately 11dB gain.
The control card was developed and built specifically by the IARS for this purpose with the microcontroller used to generate the Morse code and all the control for the simplex repeater.
The unique program code has been written inhouse and developed by IARS to suit this application.
This is all installed into a 19” rack 2U enclosure mounted in the equipment rack at Maddens Plains.
Operation of the Beacon
Approximately every 10 minutes a string of Morse Code will be transmitted from the beacon.
The interesting part of this Morse code is that it is part dynamic.
There are two values which are actively monitoring the unit on site.
The first is the Temperature inside the cabinet in degree Celsius
The second is the system voltage currently at the repeater site.
The Morse code message is structured as follows:
VK2RMP experimental beacon test QF55LR TEMP XX.X Deg. SYSTEM VOLTS XX.X
During the Beacon operation the Simplex section will not operate.
The beacon will not transmit whilst the simplex repeater operation is in progress and will wait until the simplex process is complete.
Operation Procedure of Repeater
It is a simple process after selecting the Repeater frequency.
It is recommended you wait for at least 10 seconds or press your PTT once for a short test, if a tail and beep comes back to you, you good to go.
If not, it may be that your signal is not getting in OR someone is using it on the input that you cannot hear.
Pressing the PTT quickly to see if it responds (similar to a duplex repeater tail) will not interfere with someone else’s transmission, as long as the PTT is quick, and not multiple times, this could be annoying for someone trying to record.
Summary : Onequick one second PTT should give you a Tail and a roger beep. If not someone is using the repeater OR your signal is not been received by the beacon.
If there was no response it may be good to wait for at least 30 seconds to see if the unit was in use before attempting the PTT again.
Once roger beep is received and you are ready to commence your transmission, it is best to operate the PTT button for about 1 second before speaking or transmitting data of pictures.
The reason for this is to stop any clipping at the start of the transmission. The repeater has a 0.5 second noise suppression timer to avoid false triggering.
CTCSS was not used to do this as many experimenters don’t have encoders fitted to the 23cm gear.
Once you release the PTT there is a one second delay before the recording stops and the current reception cycle is terminated, this is to allow for short signal drop off’s during your over.
Without this timer, a signal drop off may prematurely terminate your over and begin re-transmitting what you have just transmitted, whilst you are still recording, rather messy.
After this one second delay the repeater will commence to re-transmit your over. When the repeater has concluded your transmission you will hear an audible ‘Rodger Beep’ of approximately 750Hz.
It is after this Roger beep that a respondent or yourself may commence the next transmission. If you do not hear the ‘Rodger Beep” wait until you do.
Please make the transmission long enough to finish the job and short enough not to cause any others to be impatient.
Remember to be patient - including hearing the “Roger beep” - and avoid any difficulties.
When transmitting data modes such as RTTY or SSTV, ensure the transmission DOESN’T exceed the 150 second time window, because if you do, the signal will be unintelligible and fail.
Keep to the simple operating procedure and you will be able to enjoy our hobby that much more.

portable QF46xe

last week was portable & mobile around QF46xe, staying at Jenolan Cabins,  I setup a 2/70  vertical on a 2.5metre portable mast, here are some signal strengths for some repeaters I could key up, or simply heard them, as of 22nd July 2019.

146.650 VK2RDX Mt Bindo  60/9
146.675 VK2RUW Knights Hill s5
146.800 VK2RLE Heathcote s9
146.875 VK2RMB Terrey Hills 20/9
147.000 VK2RWI Dural 50/9
147.125 VK2RAG Somersby 50/9
147.200 VK2RCW Gowan s3
147.250 VK2RNS Hosrnsby 10/9

438.350 VK2RHT Chatswood 50/9 (digital)
438.400 VK2RMB Terrey Hills s3 (digital)
438.450 VK2RCF Carlingford 40/9
438.525 VK2RWI Dural  s9
438.575 VK2ROT Paddington 10/9
438.600 VK2RWI Dural s6 (digital)
438.725 VK2RMP Maddens Plains s7 (digital)
439.500 VK2RCG  city  30/9  (digital)
439.750 VK2RHP Horsley Park 20/9 (digital)
439.800 VK2RCG city 30/9 (DMR)
439.925 VK2RON Hunters Hill s6
439.950 VK2RAG Somersby s7
439.975 VK2RHS Hornsby 10/9


The 23cm repeaters was using a grid pack in vertical polarised position.
1273.100 VK2R?? Sugarloaf    tried it but nothing
1273.200 VK2RWC Chatswood 60/9
1273.500 VK2RAG Somersby s3
1273.500 VK2RWI Dural s5

The beacon was received using a  grid pack in horizontal polarised position
1296.420 VK2RWI  Dural s9
 
As for 6metre repeaters, I had my quad band FM in the car, I tried the following 6metre repeaters,
53.625 Sugarloaf, 53.650 Maddens Plains, 53.725 Somersby, 53.850 Dural, 53.875 Blue Mtns,  received none of them.

I made several contacts on 23cm repeaters over the week. Glad to see people using the 23cm repeaters.

2018 Events

Easter Holidays  -  30th March to 2nd April -  going to Central West NSW for portable VHF, UHF and SHF portable.

WIA AGM  - 18th to 20th May  -  up on the Gold Coast QLD, at SeaWorld Conference Centre.

GippsTech Conference (VK3BEZ.org)  - 6th to 8th July at Morwell, VIC.

October Longweekend - 29th Sept to 1st October - going to Central West NSW for portable VHF, UHF and SHF portable.

Mountaintop portable - Oct 2011

We went to QF46 from 2nd to 6th Oct, operated on 23cm EME WSJT, my first 23cm EME contact with Bruce PY2BS in Brazil. This is the 5m dish down at the house. Tim VK4TIM came down from Brisbane.

Also did some AE contacts on 144.200 morning sked, working VK1, VK3 and VK4 over a couple days, using the 8el 2m yagi, FT-221 with Tono amp, giving approx 60w PEP, need to get some more drive from the FT-221 to get 300w PEP for next time. Contacts included VK1BG, VK1KW, VK3BJM, VK4OX, VK3DUT & VK3VFO on 144.200

And made contacts on 40m, 10m, plus worked Tim VK4TIM mobile2 on 52.525, as he approached from Dubbo to Orange, prior to that on the Coonabarabran rptr (146.800) whilst he mobile up past Gilgandra.
On 40m, worked club members VK2HL, VK2XE & VK3BQ/7on the 80m Loop antenna.
On 10m, worked T32C, I0KNQ plus others, 10m FM was useless, with wall-to-wall Indonesian fishing boats blocking most of that band, did hear a BY station on 29.600 a few times.

Did some work on antennas, added a few more basic antennas to the shed, e.g 2m 5/8th, 2m 1/4 wave, 70cm 1/4 wave for rptr usage. Fixed the 13.8v power distribution, for easier connection of xcvrs when working in the shed. New larger shed is planned.


More pics on the Flickr site. I still need to add the screenshots of the EME contact here.

Easter/Anzac holiday weekend Photos

some recent photos from the Easter/Anzac long weekend 2011:

http://www.flickr.com/photos/33440868@N06/5708536553/in/set-72157612214659210/

you will see these are labelled as Easter 2011

Easter/Anzac holiday weekend

counting down the days until go portable DX'ing, location QF46pu (896mASL) and QF46pv, or known as Gowan which is n.w. of Bathurst NSW, across 22nd to 26th April.

Operating bands: HF, VHF, UHF, SHF
modes: FM, SSB and maybe digital modes,

Planning to make some contacts with other local MWRS club members, some of which will be also portable at Coolah Tops National Park (grid QF58) on 40m (daytime) and 80m (nightime)

check www.vklogger.com for operations.

Easter/Anzac holiday weekend

planning to go portable, QF46. HF, VHF, UHF & SHF activity on the drawing board.
see vklogger.

another great photo

another great photo with 23cm EME dish in foreground and what looks like a 70cm yagi and 2m yagi possibly for terrestrial DX. This is 10 min timelapse looking to the southern polar centre.

great photo

Amazing pics of 3m dishes (for 23cm operation) by Bob VK2ABP, with TH-3 for HF in the background.
One dish for EME and one for terrestrial DXing.
The red glow is from the campfire.

23cm operating

Last Friday, 1st October, operated stationary mobile from Seaforth Oval, took the 23cm FM and the Double Quad antenna and 3m coax,

we been trying to do some tests out to Dave VK2JDS, on previous attempts to use this site, there has always been some sporting event on, the reason for this site, is it is high, but has a clear, unobstructed view to the west, from the carpark, the land dips away acrossd the playing field and there are nil trees to block the path, you can see clearly the Blue Mtns, there are other nearby locations that might be higher, but usually they obstructed by large trees.

For this test, Dave using his all mode for 23cm into a 3m dish, located on his mountain top at 890 m ASL, aimed at Sydney. We used 1270.000 MHz simplex, Dave first tried sending a carrier and I opened the mute on my FM rcvr to try and detect, it was hard to tell if the noise floor changed or not, so I ran 10w FM, Dave tried detecting it in SSB mode and he was successfully able to detect my carrier, so we proved it was possible over the 190km path.

23cm operating

Scanning across 23cm, found a couple people chatting on 1294.000 FM simplex freq, a VK3HDX/p2 in Neutral Bay and Vk2HGX at Hurstville, what a surprise, some more people on 23cm FM, made contact with VK3HDX/p2 good Q5 signal both ways. Not bad for an antenna sitting on my downstairs window sill.

I think I heard them or someone else on the Dural rptr 1273.500 yesterday.

I must build a phased stack of Double-Quads as an array, much better proposition to a stack of yagis on 23cm.

23cm operating

As of 20th December, I now have 23cm FM gear, an FT-223R with 10w and a Double-Quad antenna, did some testing against VK2RWI Dural beacon (1296.420) and repeater (1273.500 o/p and 1293.500 i/p) after wasting a couple days trying & monitoring the rptr on the wrong freq.[note: this rptr has been listed incorrectly in past callbooks as 1273.750]

The Double-Quad antenna works well, you can really tell the difference of both the beacon and rptr signal and their respective polarisations when switching between horizontal and vertical for each device.

Playing with the 23cm is interesting, totally different to 2m & 70cm, I found trying the antenna in different places around the house that the best signal from the beacon & rptr was by aiming at the city, which is at a beam heading of 180 deg, whereas the Dural site it is a beam heading of around 280 deg, which appears to indicate that a large lump of steel, glass & concrete is providing a better path than aiming through trees and over a ridge.

Made my first 23cm contact with Keith VK2ZZO on Sunday 27th Dec at 12.20pm local EDST to Lane Cove direct & via the Dural rptr. I heard a few people call back on the WIA broadcast.

Dave VK2JDS reported he could hear the Dural beacon (1296.420) from out near Hill End (QF46), but the rptr was way down, but still interesting, as he couldn't hear the 2m or 70cm from Dural rptrs, which is about 180kms, but over the Great Dividing Range.

Dave VK2JDS (QF46pv) worked Bob VK2MRP/p operating at Mt Ginini (sth of ACT) using the same radio and antenna with 1w on FM.

In summary, I am monitoring either 1294.000 FM simplex call freq or 1273.500 VK2RWI Dural rptr. Hope to try some coastal ducting soon.