AD5DZ's new "Push To Talk" RIG VOX activation module demo - QRQ CW example

[Chuck aa0hw]

This demo shows the AD5DZ CW KEYBOARD sending CW at 60 wpm from a remote OP's location to a RASPBERRY PI 2b which is using the RIG's own sound card as its own sound card in order to send CW on that rig remotely, over ip, using AFCW MODE on LSB. In order to preserve the first bits of the CW ELEMENTS, when using VOICE VOX MODE on the RIG, on LOWER SIDE BAND, a PTT ACTIVATION TONE is sent ahead of the actual CW TONE...so that the RIG's PTT circuit is fully on before the CW TONE ARRIVES...the correct timing of this operation is performed by the AD5DZ's new PTT MODULE...which has both a DELAY setting and a HANG TIME setting...the PTT MODULE "keys" 2 AD5DZ sine wave oscillators, the PTT oscillator pitch is 5555 hz(too high to get transmitted by the RIG's brick wall low pass filter) and the CW TONE oscillator is 680 hz

NOTE: for AFCW MODE the volumes of the CW pitch must be lower than the threshold value of the rig's ALC circuit...so that no rise time distortion(which causes unwanted harmonics) occurs...on this K3S that volume amount is about -12 db...(the 5555 hz PTT tone is only -22 db...just enough to activate the RIG's VOX circuit)

[Steve Steltzer]

Interesting conversation, not what you hear on the air everyday.