I bought a Timewave PK-232 w/DSP TNC some years ago and just recently
placed it into operation. I have tried the PKTERM '99 program and I
can't say that I really liked it very much. I have tried to de-code
morse via the TNC and it seems like the very best that I can do is
de-code at about a rate of 75%. I am not impressed. I used MT63 to
decode transmissions via a soundcard and that worked very well. So what
good is my TNC when so many programs are now free and found on the
internet and all that is needed is a cheap computer with a soundcard?

Roger 507

wrote:

I bought a Timewave PK-232 w/DSP TNC some years ago and just recently
placed it into operation.

That's the problem. "Some years ago", the TNC -was- the way to go. Not
so today.

I have tried to de-code morse via the TNC and it seems like the very
best that I can do is de-code at about a rate of 75%.

This is typical of -any- type of non-human Morse decoder (even a sound
card). These devices are susceptible to QRM, QRN, character spacing, how
good the sender's "fist" is, etc, things that the human brain decoder
can compensate for.

So what good is my TNC when so many programs are now free and found
on the internet and all that is needed is a cheap computer with a
soundcard?

Well, you've essentially answered your own question. Except for the
"TOR" modes (AMTOR, PACTOR, G-TOR), a sound card and software is the
better way to go (and sound cards will also do SSTV, Hellschreiber and
many other modes, both new and old).

wrote:
That's some good information, K8VT. It would be interesting to hear more
on the subject of digital shortwave radio communications from the
members of this group. A cheap SW radio, a cheap computer with a
soundcard and a free program is all that seems to be required. Is there
anything else that we should be aware of K8TV ?


Roger 507

Well, two comments I should have added to my original response:

The TNC, in addition to the "TOR" modes is also great for packet
(AX.25). Unfortunately, packet, as used by hams, is mostly dead.
However, many satellites still use AX.25 for sending telemetry, the
latest example being "Pehuensat-1, the new Argentinian satellite.

I also should have stated the obvious, that software (as used by sound
cards), is much more flexible than firmware (as used by TNCs).
------------------------------------------------------

To address your comments above, yes, a cheap computer, sound card and
software is fine. However, I might disagree with you about "a cheap SW
radio". Receiver stability and selectivity are very desirable
characteristics for copying digital and usually don't come too cheaply...

Granted, a quality receiver is the way to go. I use here at this
location both a Icom R71A and a Yaesu FRG-7. I like to use the Yaesu for
listening to the routine shortwave broadcasts and some of the ham radio
voice transmissions. The audio quality is great. The filter for the
Yaesu seems somewhat wide. The Icom R71A is my favorite for digital
work. I can see that digital shortwave communications will be the
growing sector of shortwave and Ham radio in the future. Just a cheap
computer (I paid 25 bucks for mine) and a cheap computer soundcard is
all that seems to be required, and a good shortwave receiver.
What are some good internet sites for some free downloads of digital
software programs, K8TV?

Roger 507

wrote:

What are some good internet sites for some free downloads of digital
software programs, K8TV?

Roger 507

Go to www.ac6v.com, choose "Software", then either "Digital", "SSTV" or
"RTTY". (and yes, I realize that SSTV is not digital, but you might
enjoy it. Try MMSSTV).