DATV-Express Project – December update report

[KenW6HHC]

Writing software to run at Operating System low levels and at the FPGA coding levels is challenging, complex, and can be very frustrating. The DATV-Express Project team has made the bitter-tasting decision that the one remaining significant software bug will postpone the sale of the DATV-Express product in early January to the general ham population.

Charles G4GUO has been working diligently to resolve a list of five remaining DATV-Express software bugs that we knew about at the start of December. Four of these five problems have now been resolved. Only one software bug remains…a design flaw somewhere in our PCR redesign of the Hauppauge MPEG2 faulty (on Linux) PCR clock and packet timestamp. Ken W6HHC reports that most descriptive symptom of this bug is that “transmission video will freeze up on my STB in between 2 minutes and three minutes of PTT”. Other STBs and DVB-S analyzers are more robust. But as Ken explains…the project team does NOT want the user’s first experiences of our product to be “reception of my video froze up”.

The project team has resolved that general sales to hams will begin as soon as this last bug is resolved. Sales to programmers who are willing to work on software development will continue. Interested and willing programmers should contact G4GUO by e-mail to obtain a “PromoCode” if they are willing to assist in working on DATV-Express software. A discounted price of US$200 (including all world-wide shipping costs) is available to programmers with a PromoCode via PayPal on the website.

The good news this month is that the DATV-Express web site is now fully functional, thanks to the efforts of Bob N8NT. Go to the web site at

http://www.DATV-Express.com

You must register on the web site in order to see the full contents there.


More good news is that Art WA8RMC has completed a five-page datasheet for the DATV-Express product that can now be downloaded in PDF from the web site.


Even more good news is the latest draft of the DATV-Express Users Guide (now up to 36 pages) can also be downloaded from the web site.


The DATV-Express Project team is committed to resolve these issues and start up production sales as soon as THIS LAST SOFTWARE BUG IS RESOLVED.

73…de Ken W6HHC

[F4HDK]

Thank you for this great project!
I am very interested in it. It can be a great improvement for DATV.

I have one question about it: will it be possible to send a "transport stream" directly to this modulator board? I mean via a 8 bit parallel interface? Like on the SR-System mini-mod boards? I assume that such an interface is not available, when I look at the pinout of J4 and J6. But I would like to have a confirmation of that. My goal would be to make for example a DATV repeater without the use of a computer.

Thank you for your answer.

Guillaume - F4HDK.

[G4GUO]

Hello Guillaume,

There are not enough spare pins on the FPGA to do that directly.

However a small Chinese FPGA board (15 Euro) could be used to convert
from the 8 way parallel interface to a serial interface to communicate to the
board. However a far amount of software would be needed.

We are very stretched for programming resources at the moment so it is
unlikely to happen. However all the source code and hardware designs will
be made available so if someone wants to they can have a go at doing it.

- Charles G4GUO