Australian Ham Radio Discussion Forum ( AHRDF ) - Brisbane beacons VK4RBB off air for a time

Greetings to all.

Geoff VK4KJJ and I today visited the site of VK4RBB to investigate, with Rob VK4ZDX, the reason that the 24 GHz transmission has apparently failed. We have discovered that an Elcom ILCDFSL-1201 synth that generates the 11.39 GHz LO signal for this transmission has zero output.

So, in order to effect the necessary repair, I have brought back to the work bench here the main RF box that feeds all the beacon transmitters. It follows that all VK4RBB transmissions have ceased until the main RF box is placed back into service.

Apologies for the interruption to beacon services! I am expecting that it will be off air for only a few days.....

Cheers and 73,

--Doug Friend, VK4OE.

Greetings again to all readers!

I am happy to report that, as of this morning, the 'RF Box' from the Brisbane VHF Group's VK4RBB beacon has been reinstated, and that all licensed output frequencies are now back on air. Smile

Finding what was wrong with the Elcom synth has not been conclusive - it may be that a slide-on connection to it could have not been making reliable contact - so it will be a waiting game to see if the 24 GHz transmission stays 'up' as the weeks go by.

Some other work has also been effected to improve the shielding around the liquid crystal display so that the LCD should be more immune to RF interference. Again, time will tell.....

Cheers and 73,

--Doug, VK4OE.

Greetings to all!
Today all of the VK4RBB transmissions have been turned off to enable repair of the 24 GHz beacon electronics again - apparently a different fault this time. There is one box which contains all of the PLLs and mixing electronics for all seven licensed output frequencies, and it's that box which has had to be removed for service.
Stay tuned for notice of when it is all switched back on!
Cheers and 73,
--Doug, VK4OE.

Greetings to all readers.
I am pleased to report that, after some attention over a couple of days by Stefan VK4CSD and myself, all of the output frequencies for VK4RBB are now back on air.
For the record, in addition to showing that they are all 'ACTIVE', I have amended the 'Beacons' list on the 'VK-Logger' to show that the output powers of both the 10 GHz and the 24 GHz transmissions are now each close to 0.5 Watts, a more accurate reflection of their current status.
Cheers and 73,
--Doug Friend, VK4OE.