Se você não tiver certeza se o seu equipamento SELCAL está funcionando corretamente, você pode solicitar um SELCAL check em uma freqüência de rádio habilitada para HF. A unidade ATC enviará seu código SELCAL para fins de teste.
I'm not sure my selcal unit is working, is there anywhere I can test it?
Yes, several places. If you are located in:
- Europe or east of 30W on the North Atlantic, call Stockholm Radio
- Eastern USA/Canada or west of 30W on the North Atlantic, call New York ARINC
- Western USA/Canada or Pacific, call San Francisco ARINC
- Asia - daylight hours, call Singapore or Manila Radio on 8942 KHz USB
[...] All selcal checks are free of charge - just call the station with the aircraft registration mark and when you receive a reply ask for a selcal check and give your selcal code. The operator will send out your selcal tone and - assuming the selcal unit is working - you will hear a chime in the cockpit. Acknowledge by replying 'selcal check okay' and you're done! If your selcal check doesn't work the first time it is worthwhile asking for a 'double' which means you get 2 sets of tones sent out back-to-back and often cures any issues.
(Source: www.selcalweb.co.uk)