Wednesday, February 1, 2023

The 3Y0J bandplan collides with VarAC

Screenshot from part of the VarAC package

 The title might be a little cryptic for some of you. 3Y0J is the callsign from a DXpedition to Bouvet Isl. VarAC is a upcoming popular digimode. The DXpedition will probabely be QRV within a few days for about 2 weeks. I didn't notice it before but through the VARA HF users fb page I became aware of it. The bandplan for the 3Y0J Dxpedition has two FT8 frequencies that are exactly on the VarAC main calling frequency. It is not clear to me why they have choosen these frequencies anyway since  DXpedition normally use pre defined FT8 frequencies. Anyway 14.105 MHz and 21.105 MHz are used for calling, ping requests and beaconing by many VarAC users. Since the broad 500KHz VARA signal is at the centre of the waterfall it is not the DX chasers that have a problem, but the DXpedition will have QRM. Something to consider when calling 3Y0J on FT8. Here is the bandplan:

3Y0J bandplan, click to enlarge

Since VARA is a very robust mode I don't expect VarAC users will have much QRM from the FT8 callers. Most of the users are unattended stations anyway. Beaconing and messaging goes automatic.


MadDogMcQ said...

That’s a coincidence - a mate was just telling me about VarAC/HF and my first reaction was “are there particular frequencies assigned to this mode, or will there be upsets”?

I need to have a play!

73, Tom, M7MCQ

PE4BAS, Bas said...

Hello Tom, VarAC is really worth trying. Although most stations are only beaconing you can try and make an QSO in the end. Just a few days ago I had a decent QSO with someone from Belgium. I could hardly hear the signal by ear but the software had no troubles decoding. 14105 is the main frequency, but I think with the DXpedtion going on it is better to move somewere else. 40m seems to be interesting from what I hear. 73, Bas

PG5FRL said...

Auch... ongelukkige keuze. Ook de VarAC aanroepfrequentie op 17 meter ligt erg dicht op de FT8 frequentie van Bouvet. Op de een of andere manier verwacht ik een hoop commentaaar op de DX-Clusters. Jammer dit :(

PE4BAS, Bas said...

Inderdaad ongelukkige keuze. Het is mij ook onduidelijk waarom ze juist deze frequenties kozen en niet de standaard DX FT8 frequenties. Of het veel problemen gaat opleveren? De tijd zal het leren. Eigenlijk best stom dat het niet eerder iemand opgevallen is, dan hadden we nog protest kunnen aantekenen. Nu is het daar denk ik een beetje te laat voor. 73, Bas