SELCAL WHITE
 

Hi
Does SELCAL still work when it is white (So the captain has selected VHF2 or the first officer has selected VHF1)
Regards,

SELCAL is done via HF.
When the station calls on SELCAL, the pilots will hear a chime and the selected receiver will turn white. The pilot will then have to reset the SELCAL by pressing the highlighted button.

If the pilot does not reset it, he/she will not be able to receive the chime next.

Thanks,
When we reset SELCAL, does it become green? How do we turn off SELCAL?
But what if we change the frequency between two SELCAL, for example we tune it 117.54, we then receive SELCAL, it turns white. Then we change the frequency, does SELCAL remain white or does it come back to the normal position, green or does it turn off?

I can only answer for Boeing aircraft.
You don't change frequency unless told to. When you change frequency you will need to do another SELCAL check with that station.

SELCAL is not only for HF - is used frequently on the NAT on VHF routes as well

Thanks to everyone! Just correct me now:
AIRBUS

1) SELCAL is used for VHF
2) When the captain has selected VHF2 in RMP 1 or if the first officer has selected VHF1 in RMP 2, the SELCAL turns white. Just need to reset it. It will turn off and you can start it back.
3) When you are changing a frequency and you just got a SELCAL, the SELCAL turns white. When you go on the new frequency, the SELCAL turns off.
4)When you reset a SELCAL, it turns green.
5) When you received a SELCAL, to turn off SELCAL, you need to press SELCAL in this order: White (received SELCAL)-Green (Reset)- Black (off)
6) When you are changing a frequency and you just got a SELCAL, the SELCAL turns white. You reset it, it turns green.When you go on the new frequency, the SELCAL turns off.

Regards,
AF330

Sorry to ask but having been in the avionics biz in Europe for forty years I had never come across a VHF usage for SELCAL. The whole point of SELCAL is that it enabled flight crews to monitor an assigned HF frequency without having to listen to all the noise and crap associated with HF reception and / or where over-zealous use of a squelch control could desentitise the radio to the point where no reception was possible.

What possible use is there for SELCAL on VHF?

Surely in order to develop a mental picture of traffic in say a 500 nm diameter circle around a ground transmitter and indeed to comply with all current VHF communication practices crews should be actively monitoring the frequency of that ground Tx. and not just listening out for specific calls to them.

Background noise associated with VHF comm is automatically squelched out or muted by the signal-to-noise squelch circuits in the airborne Tx / Rx, these being overridden only when the Carrier squelch circuits preset values are exceeded so the airborne RX should be quiet until a proper signal overides the squelch. With an active SELCAL applied to an assigned VHF frequency isnt there the possibility of flight crews missing other transmissions not intended for that specific aircraft but nevertheless providing info to the crews about other aircraft in the vicinity.

Maybe I'm being a little thick but to me SELCAL on VHF seems to be retrogresssive idea... can someone ptease explain... this is not intended to be argumentative, just looking for a justification...
Thanks,

Your point is very intresting! You have been working in the avionics biz in Europe, so could you please answer my (silly) questions for Airbus? ;)

AF330
Regretably no... my experience of SELCAL equipped aircraft is limited to an extensive fleet of UK based but HF equipped Falcon 20 biz jets.
During a series of avionics modification programs we deleted the Selcal system as an unwarranted expense and removed the HF boxes refitting them only on an 'as required' basis when transiting to / from or operating within the Far East.
So sorry, cant help.
pp

Hi Phalconphixer
It doesn't matter! Thanks for your reply.
If anyone could confirm these sentences, it would be really nice.
I made some search on google and here are my explanations on my questions:

1) SELCAL is used for HF and may also be used for VHF: Confirmed by Phalconphixer and wikipedia SELCAL.

2) When you press the SELCAL button, it turns green. So SELCAL is now working on the frequency you have tuned. Confirmed by:
Radio Management Panel | Radio Selection Buttons

3) When the captain has selected VHF2 in RMP1 or the first officer has selected VHF1 in RMP2, the SELCAL turns white. Confirmed by: Smartcockpit A320 Communications. SELCAL won't work till we press the white button. After pressing it, SELCAL will turn off. Need to start it back (so it will turn green). Not confirmed, by deduction.

4) When we receive a SELCAL, it turns white and we need to press the button to receive the next chime (so SELCAL will turn green). Confirmed by: B737900er (even if he has said it for Boeing, I don't think it will really change for Airbus, but still needs to be confirmed!)

5) To turn off SELCAL after having received a Scheme, the SELCAL will go threw these colours: White (received a Chime)-Green (have reset SELCAL)-Black (SELCAL has been turned off). Confirmed IF upper points have been confirmed...

6) You have received a chime, so SELCAL is white. You don't reset it and you change the frequency. SELCAL will turn off. (It will be black). Not confimed. Still have a doubt, will it remain white or will it turn off? I don't think it will reset (will turn green) by himself. My default i THINK it will turn off!

Thanks to confirm- reconfirm all these points for me,

Kind regards,
AF330

http://www.pprune.org/questions/396543-vhf-selcall.html

VHF Selcal is still being installed in certain avionics fits to brand new, recently certified aircraft.

CPDLC, ADS-C etc, and it's future mandates will surely supersede this.

Thanks 500 above,
Phalconphixer has now got his answer! ;)
Could you confirm everything written is correct or just give an opinion if you think that my post should be right?

Thanks...

The SEL white light on the RMP has completely nothing to do with SELCAL. And it is not a button - unlike the other ones with that have a green light.

Sorry,
FD.