VK4RBB - Brisbane beacons back on air

[VK4EA]

Thanks to the Brisbane VHF crew, VK4RBB 70cm, 23cm, 13cm beacons are back on air, and introducing the new 6cm beacon. All are GPS locked on xxxx.440, modulation varies between CW, tone and JT4.

10GHz and 24GHz beacons are still under construction, it will be a few months until they are on air.

A huge thank you to Doug Friend (VK4OE) for the construction, with contributions from Rex (VK4REX), Bob (VK4XV) and Geoff (VK4KJJ).

I've spotted the beacons on the logger so you have a bearing to them, reports welcome on the logger.

[VK4KAY]

Received this going into the warmest part of the day - which is proving for better signal quality into Brisbane through the mountains in the cooler months.

Beacon is just audible at these levels.

The doppler shift in the middle is AE from an A330 losing height over the greater Brisbane area - generally between Ipswich and Upper Mt Gravatt

Andru
vk4kay

[VK4JAM]

A big thank you to the Brisbane VHF crew. I am hearing the VK4RBB 70cm and 23cm beacons stronger than ever.

I like the JT4 addition . A decode off 70cm is attached, still having difficulty decoding 23cm. Perhaps it is not JT4D???

73
Andrew
VK4JAM

[VK4EA]

Jt4f 23cm and above

Sent from my SM-T805 using Tapatalk

[VK4JAM]

Hi Peter,
Thanks for the info - working great using JT4F.
23cm decode attached
73
Andrew
VK4JAM

[VK4AQF]

5760.44 copied from inside car at elevated road about 5km from Murrarie, not LOS.
All others (3 I can hear) copied and decoded on JT4 in the garage of VK4AQF.
Will look forward to seeing 3400 running..well lets hope.

de Quentin 4AQF.

[VK3KGR]

You may be aware the VK4RBB beacon has a "feature" when very occasionally there is no signal for a whole minute. To try to rectify this, a modification was made to the beacon this afternoon. Please report here if you notice the beacon is still missing minutes occasionally.

If you do notice missing minutes we would also like to know if it is on all bands at once or only on one band.

Geoff VK4KJJ

[VK4OE]

Hi Geoff and other readers.

As far as I am aware, during the last two months there have been no 'missing minutes' noticed. This is the outcome expected by us following the small modification to the ZLPLL boards 'controlled' by the ZL2BKC multi-beacon controller, as recommended by the Wayne himself, ZL2BKC.

Now that I am back from overseas, work on the 10 GHz and 24 GHz beacon hardware for 'RBB will resume.

Cheers and 73,

--Doug, '4OE.

[VK4BG]

Hi Doug,

For your info, if you don't already know, the 1296 Beacon is audible in Hervey Bay 99.5% of the time....vary rarely does it disappear, and the JT65 tones are the most noticeable if things are a bit weak...and it is spot on frequency !! ( Rubidium or GPSDO locked here, depending on how I feel on the day ).

Actually, I only have the Kuhne transverter locked...the Elecraft KX3, unlike its bigger brother the K3, does not have the ability to be locked to an external source...but Elecraft came out with an " extended frequency calibration " procedure that really tightened things up on the KX3...I'm guessing it is now capable of plus/minus 5 Hz from my fiddling here. A/E enhancement is noticeable on most days.

73
Glenn
VK4BG

[VK4OE]

Thanks Glenn for that encouraging report!

Yes, our testing prior to installation showed that the output carrier frequencies are all better than +/-1 Hz of where they are supposed to be and, given continued lock to GPS transmissions, they should remain that way.

Incidentally, the 'JT' parts of the transmissions are JT4D on 432 MHz, and JT4F on all frequencies above that.

And it has been previously observed (personal communication from ZL2BKC) that when listening with our ears to a very weak beacon signal, it is often easier to be sure that the signal is there when listening to the JT4 tones than it is when listening to a plain carrier with/without Morse ident! Others may like to comment on this.....

Great to hear from you!

--Doug.

[VK4OE]

Greetings to all.

This coming Sunday morning will see the VK4RBB suite of beacons cease transmission for a few weeks. Weather permitting, the beacon hardware will be removed from the present location at Murarrie and prepared for later installation at the new location on Mt Cotton - QG62OJ52.

The Brisbane VHF Group trusts that these forthcoming off-air weeks will not be too much of a problem for users of the VK4RBB beacon transmissions. When the hardware is re-installed I will advise readers by this medium again, as well as by updating the VK-Logger beacon listings.

Best 73,

--Doug Friend, VK4OE.

[VK4OE]

Greetings to all readers.
This is just a short note to advise that, as of this afternoon, all transmissions from VK4RBB have been turned off to allow for trouble shooting of the 3398 MHz hardware which reportedly has failed in recent days. Initial inspection pointed to a damaged DC power connector on the main power supply, the removal of which has necessitated switching off the whole station. In the ensuing 'down time', both the 3398 MHz and the 5760 MHz transmitting hardware will be thoroughly checked, as well as probable replacement of the DC connectors on the PS.
Here's hoping that the off-air delay will not be too great!
Cheers and 73,
--Doug Friend, VK4OE,
Brisbane VHF Group.

[VK4OE]

Greetings to all!
All the VK4RBB signals are now back 'on air', as of about an hour ago.
Please report by way of 'spotting' on the VK-Logger.
Cheers and 73,
--Doug, VK4OE.

[VK4CZ]

Thanks Doug - great news.

[VK4UH]

Thanks again Doug for all of your efforts
KJ

[VK4EMS]

great work Doug we all appreciate you endevours with regard to keeping the beacons up and running! stirling effort as usual !