BATC Forum

I am just starting to look into D-ATV here in the US. I have found only one repeater in use in Ohio (WR8ATV) and they are using QPSK-based DVB-S format. They are using "Free-to-Air" satellite TV receivers. And uses a MPEG2 data encoding.

I have heard that there has been some point-to-point experimenting here in the States but I have no idea what format was used. So I am starting from almost zero.

Because of your experience in working with D-ATV for sometime and being so far ahead of us in the US, I thought the forum would be a great place to ask a few questions.

Questions:

Is the format that WR8ATV is using the best direction to take or are you doing something different?

Is the format that WR8ATV is using a "High Definition Digital Television" or just "Digital ATV"?

And I saw another posting on the forum about "problems with AGAF DATV Board Set". The question is, where are you getting your equipment and is this board set a vender for equipment?

I publish the "ATV Newsletter" and I might print your replies in the newsletter which has a circulation over 900. If you would prefer not having your reply printed please let me know.

If you would like to subscribe to the ATV Newsletter just send me an email to
atv-newsletter@hotmail.com and I will add you to the mailing list. The newsletter is published weekly and it's FREE.

73's
N6IFU
Bryon Foster
Editor and Publisher of the "ATV Newsletter"

Hi Bryon
I see nobody has replied so I will try.

Yes the system that WR8ATV is using is what is mainly use here. DVBS and MPEG2
We tend to use ex-broadcast equipment either direct from the broadcasters or from ebay and similar.
We use a symbol rate of 2 MS/s and FEC of 1/2 or 3/4 on 70cms (436 MHz) and
4 MS/s on the higher bands. Although a whole variety of data rates are used by some people.
The reason that we use DVBS is because the bandwidth used is proportional to the symbol rate.
So you match your data rate to the bandwidth available.
Very useful on 70cm where we try to keep the bandwidth down to 2 MHz.
Some countries, especialy France use even lower symbol rates.
Source material is usualy in 625 line PAL.

As for the future, I guess we will change to MPEG4, wide screen, and HDTV at some stage when the equipment becomes available.
Still using DVBS and it's varients.

The countries that are most active with DATV are Germany, France, UK, the Netherlands, Scandanavian area, Australia and New Zeland.
(Apologies if I have left anyone out!)

I hope this helps,

73's, Dave, G8ADM

Thank you Dave for your input. I will be publishing your reply in the March 11th edition of the ATV Newsletter.

N6IFU
Bryon Foster