Page 1 of 1
Kenwood TM-V71A
Posted: Wed 22 Sep 22 2021 7:39 pm
by Daniel Wee
Re: Kenwood TM-V71A
Posted: Sat 09 Oct 09 2021 12:19 am
by Daniel Wee
Re: Kenwood TM-V71A
Posted: Sat 09 Oct 09 2021 8:18 pm
by Daniel Wee
Second digipeater hardware
1. Vention USB soundcard (Challenger SGD10)
2. Raspberry Pi 4 8GB
3. PR1 and PKD pass through 1:1 Bourne audio transformer with 10uF on radio side
4. GPIO 18 as PTT
5. GPIO 23 as DCD
Re: Kenwood TM-V71A
Posted: Mon 11 Oct 11 2021 1:13 am
by Daniel Wee
Packet levels
On our implementation, with the notch on the top and looking into the connector from the 1-o'clock position clockwise:-
1. PR1 from the radio into the TNC
2. PKS - PTT keying
3. output from the TNC to the radio PKD (calibrated for an output of 40mV p-p)
4. Ground to radio DE
The output from the soundcard is quite strong and requires a 10k-pot to bring the level down. That said, the alsamixer values we settled on in the TNC are as follows:-
Speaker 28
Mic (muted) MM
Capture 48
AGC (muted) MM