VK3RRU GPS locked

[VK3JUG]

VK3RRU on 144.438MHz FSK is back on-air GPS locked. Following the unknown "expiry" of the 3XDK exciter, a complete new beacon is now running, consisting of an RF Innovations EX paginging transmitter @ 25Watts fed with a PicoSync GPS disciplined oscillator 10MHZ reference and keyed by and Arduino.

Looking for commments on Freq. error please.

(Keying format will change but is currently ID followed by 20sec carrier and 20sec rest)

[ADMIN]

VK3RRU on 144.438MHz FSK is back on-air GPS locked...

...Looking for commments on Freq. error please.

Great to hear!
Some will have reservations about being able to report to 1Hz, but if this stirs up renewed interest and activity, and encourages more to update their own station's capabilities, it can't be a bad thing?
I'm sure there will be rigorous debates over who's closest to actual, and which scheme is best!

Thanks for updating the beacon database too.

I guess it goes without saying, just because something is 'locked' doesn't mean it's on absolute x frequency, as there may be fixed offsets introduced somewhere along the line.
So it can become useful to spot your report to the best accuracy you can, so custodians can check reports.

[VK3JUG]

Still looking for an idea of exactly what the Freq. VK3RRU 144.438MHz is actually transmitting on before i put it back at the beacon site permanently. Have upped the output to 40W now i have a switched mode supply feeding it. Any suggestions welcome, my test sets give me 3 different readings as none are locked to a reference.

[VK3HZ]

Hi Peter,

Is that correct that it's running vertical polarisation?

I'm seeing something extremely weakly in Melbourne on 144.437,983 MHz. It's not doing 20 sec on, 20 sec off so it must be a birdie. Are you able to hook it up to a yagi (h-pol preferably) and point it this way?

Regards,
Dave
VK3HZ

[VK3JUG]

Yes, is running on a vertical 4dipole array while on test, soon as i have it on freq. it can go to the beacon site and back on a single horizontal dipole.

[VK5PJ]

Hi Peter,
using my IC-910 that has a XREF in it, I have the key up tone showing at 1Khz and a dial frequency of 144.436.99 so zero beat (carrier) should be around 144.437.99

Regards,
Peter, vk5pj

[VK3JUG]

So that makes it around 10hz low, so it's in the ball park, any other advances?
I'll be away till Wed. night, so will leave it till then to adjust.
Would like to have it netted on freq. and installed onsite by the weekend as it will be awkward to work on once it's all shoe horned into the small cabinet it shares with the 70cm repeater. (Old traffic signal baox.)

[VK3JUG]

Moved up 10Hz this afternoon. Should be back at the beacon site by the weekend.

[VK3TU]

"...by the weekend."?

[VK3JUG]

Maybe not, need to add a Tx power up delay or add a reset Tx at start up as the Tx is faulting to internal ref on a cold power up due to GPSDSO not locked when Tx booting up after power fail

[VK5ACY]

I can hear VK3RRU/2m (~250km) at around S3 this morning, 0400 local (VK5 time), with tropo generally poor.

VK3RGL/2m (~540km) is at about the same S3 level with VK7RAE/2m (~915km) just a bit stronger at S4.

At times in the past - under enhanced tropo conditions - I've seen/heard VK3RRU/2m) at MUCH greater strength
of S9+20dB and more, and can hear it easily with my 13el YU7EF Yagi on its 8m boom pointed anywhere.

When VK3RRU is 'well up' I hear it easily on my dual-band 2m/70cm omni-directional vertical over this relatively
short distance. .

I will relate more information at a future time - but with a shack temperature of 7C it won't happen until the sun
comes up ! . Propagation will likely be quite a bit better in a few hours.

[VK3JUG]

Still after comments on exact freq. of the VK3RRU beacon on 144.438Mhz. Will run a few more watts for the next couple of days to see if that helps overcome propagation problems.

[VK3HZ]

Hi Peter,

I "saw" it weakly the other day and it was spot-on frequency as far as I could tell - within 1 Hz.
Can't see anything tonight

Regards,
Dave
VK3HZ

[VK1KW]

Hello Peter,

Do you have access to the top of the tower and is it possible to replace the poor 2m crossed dipole (?) for something better say phased big wheel (cloverleaf)?
Crossed dipole certainly not a DX antenna as most radiated power not horizontal. Rarely hear the beacon here in VK1.

Thanks

[VK3JUG]

It's now reinstalled at the beacon site running 35W into a Horizontal Folded Dipole, hopefully it will be easier to hear again.

[VK3BJM]

Hi Peter,

It's certainly fairly constant here (I'm 388 km away); fairly flat conditions tonight but sitting at 519 pretty much all the time.

My home 2 metre rig isn't GPS locked, so I can't comment on the frequency accuracy at the moment. Mind you, the readout says 144.4380, and the note sounds pretty bang on to my ear.

My mobile 2 metre rig is GPS locked, so perhaps I need to take it for a drive...

Nice to see it back where it should be (in more ways than one... ). Good work!

73,
Barry
VK3BJM
QF22es

[VK3BJM]

And a healthy 559 with an obliging A320 passing through the path midpoint at 34,000'... (Just north of Culgoa)

73,
Barry
VK3BJM

[VK3JUG]

Thanks Barry, It's 1 deg here this morning, the beacon lives in an old traffic light box outside at the base of a water tower and i didn't have to get a cut lunch and go hunting up and down the band to find it.

[VK3PY]

For the past several weeks I've been listening most evenings to the VK2RRU 2m beacon. I can say nothing about its frequency accuracy because none of my 2m rigs are not GPS locked. However, it is very pleasing to be able to hear it whenever an aircraft crosses the "sweet spot". Most of the time it will be a Melbourne-bound international flight which brings the beacon up out of the noise. Unfortunately, these A/C are in their descent phase (generally around 25,000 - 30,000 ft) and flying diagonally across the direct path between the beacon's QTH and mine. Also, this crossing occurs rather too far south of the mid-path. The beacon very predictably makes its appearance just as the A/C approach Logan (about 15km ESE of St. Arnaud), reaching S1-2 and disappears a minute or so later. On a couple of occasions it has been audible just above my local noise floor for hours, presumably by mild tropo lift.

Thanks to those who have been instrumental in getting this beacon up and running. It's a great resource.

Chas
VK3PY