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The TNC-Pi9k6 has a voltage range that is software select able from 24mv to 3000mv (3 volts). This range works with most radios, but I've personally only tried a small set.
There is also a 2400 baud mode, but I have yet to find a radio that will work with it. It's nice to have all those speeds, but then finding a radio that it can work with is another matter entirely.
I have a couple NinoTNC boards (ver2) that I need to start more earnest testing. Too many other spring time things are in the way, planting the garden, keeping up on the grass cutting, smoking meat, eating it, etc etc etc. Oh, and naps. Naps are important. *Sign*, retirement is such a tough life.
On Tuesday, June 23, 2020, 6:07:13 PM CDT, Tadd KA2DEW in NC via groups.io
Another issue which may be important is some radios require more audio voltage/level going into the data port. The NinoTNC has two selectable output ranges, high, for data radios, and low, for microphone audio, for this very reason. NinoTNC has 1200, 2400, 4800, 9600 baud DSP modems built in so it needs to support a wide range of radios.
Tadd - KA2DEW
On Jun 23, 2020, at 6:29 PM, Ray Wells <vk2tv@...
That's not quite correct. For receive
, the difference
between the 1200 and 9600 ports on the rear socket is that the
former has de-emphasised audio while the latter has "flat" audio
from the discriminator. There are reasons why using the
discriminator output for 1200 packet is often superior for many
hardware TNC/modems that aren't smart enough to compensate for
relative tone levels (1200/2200Hz) when they are wrong. Soundcard
style modems like Direwolf are far more capable and less particular
in this regard. If you want to know why the correct audio is
important, take a look at this site with pictures and a very simple
I know I flog that site and will continue to do so because if
everybody using packet read that article and implemented correct
audio practices there would be a lot more stations having much
greater reliability with packet radio/APRS communications. If I
sound like a grumpy old man, I am. I've been involved with packet
since about 1985 and the biggest single factor for people's
woes and failures with the mode remains wrong audio setup.
For transmit when using the rear socket, the radio will probably
select the right option depending on whether you choose 1200 or 9600
for the speed in the radio setup, like my Kenwood TM-V71A does.
On 24/6/20 3:17 am, Jim Lange wrote:
You need to use the 1200 port on the radio. The other is for high
speed packet and won’t work with a TNC that isn’t made for it.
Otherwise all is good.
OK I am thinking of trying a TNCPi with a ft
7900r, the pigate site shows the pinout for a FT 2800/2900
using the mic port. My question is my 7900 has a rear data
port why can't I use it? Her is a comparison of the 28/2900
mic pinout and my plan for my 7900. Do I need to figure out
and use the pinout for the 7900 (MH48A6J) MIC PORT instead?
Below left mic pinout from website, Below right my plan for