Re: Solar APRS digipeater #networking


Ray Wells
 

Looks like you're on the right track but given that around 3.0-3.5kHz deviation has long been recommended for packet you might think about using wideband rx for just in case. Do you have any way of looking at the packet audio going to the HT to be sure there isn't an undesirable component sneaking in?

It's not possible yet to rule out a faulty batch of modules so good luck with any replacements.

Ray vk2tv

On 14/3/20 9:40 am, John Tetreault (WA1OKB) wrote:
I know my APRS ht is transmitting narrow band, but I had considered that possibility and tried setting the 818v module to wide band just in case... Same result.

It truly is a mystery at this point.

Worst case, the guy who makes the module has offered to ship me 2 new ones on Monday....so if it is a case of them somehow being defective that should address it... Meanwhile I keep tinkering over the weekend.


On Fri, Mar 13, 2020, 6:33 PM Ray Wells <vk2tv@... <mailto:vk2tv@...>> wrote:

John,

Somebody else touched on deviation, and what you described is
typical of
the signal being over deviated for the rx module. Could it be that
the
module is configured for narrow band (nominally 2.5kHz) rx while your
test tx is sending wideband (nominally 5kHz) deviation? That you can
hear a voice modulated signal points to an audio level problem for
packet audio. Can you reduce the audio level going to the HT? Do you
have an oscilloscope so you can look at the audio going into the HT?


HTH
Ray vk2tv



On 14/3/20 9:01 am, John Tetreault (WA1OKB) wrote:
> *no, you're misunderstand.... Transmitting works fine... I can send
> successful APRS packets with this module all day, no problem.
> *
> Its on the RECEIVE side that I'm having trouble... The module has
> squelch levels of 0-8.  I've tried with 0 (wide open, no
squelch) and
> the lowest setting of 1 with the same result either way.
>
> So, what happens... For testing purposes, I connected a small
> amplified speaker into the 818v modules audio out port.... Now,
if I
> key up my HT and talk, my voice is heard loud and clear coming
out of
> the 818v receive speaker.... If I send an APRS packet from my
HT....
> You can hear the open carrier begin.... As soon as the APRS data
> "squawk" begins... Receive mutes itself... And unmutes as soon
as the
> APRS pack is done.
>
> It has an LED that lights when squelch is open...and I can watch
it,
> light comes on as soon as the HT starts transmitting, and I can
hear
> the open carrier on the receive speaker.. At the split second the
> packet data begins light goes off, and no audio out of the receive
> speaker, once the packet data ends the light comes back on, and I
> again hear the open carrier until the HT transmission ends and the
> light goes off... So the receiver is fine with voice, but as
soon as
> an APRS data packet comes over it just decides, "nope, I don't
want to
> listen to that" and mutes itself.
>
> Now... Oddly enough, if I try this same test with an 818U UHF
module
> with a squelch value of 1. (so same exact settings just different
> band)  it works perfectly.... No self muting at all.... and
Direwolf
> receives and decodes the packet.
>




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