Re: Atypical variable stars...

["Robert J. Bradbury" <bradbury@aeiveos.com>]

Michael wrote:

>   Two sites (or more? correct me if I'm wrong!) are gathering
> data each clear night.  One site's measurements are freely available
> in an on-line database; the other's will be eventually.

What wasn't clear from the documentation I've read is
how many cameras/scopes were produced/installed.  The
figures mentioned above would suggest much less than
the map I ran across that suggested sites from Europe,
the U.S. and Australia.

>   I don't know of any single document which has all the information
> on the design of the telescopes and detectors.  You can find a
> great deal of information in a number of Technical Notes; browse
> the list at
>
>         http://stupendous.rit.edu/tass/technotes/index.html

It looks like details of the electronics TN#38, camera TN#40, and
mount TN#42 may be available (though I do not see detailed schematics).

If TN#40 is correct, parts were ordered for 10 cameras (so the
question would be -- where are they???).

>   If you want to build your own hardware which is identical to the
> Mark IV, I'd guess many tens of thousands of dollars.  It is possible
> to put together simpler wide-field camera systems using commercial
> units for, oh, anywhere from a few thousand to fifteen thousand
> dollars, depending on your preferences.

I understand this.  But it looks like the engineering behind
the TASS effort is about 6 years old.  I actually built
a CCD astronomy camera using a design from the mid-'90s
for use in DNA sequencing applications though it was
never tested (long story).  Given the advances in things
like circuit density, FPGA's, "cheap" CCDs (???? for
digital cameras, etc. I am wondering if there is a more
current design/production effort to produce something
a bit less expensive that can be put together by people
with varied skills.

(One imagines auto mechanics who would have no problem
assembling a telescope "kit" but wouldn't want to touch
the electronics to EEs who have no problem putting together
a PCB from scratch but would rather avoid things like
drive motor mechanics...).

I am under the impression that TASS III was operated in drift
mode while TASS IV is operated in point and shoot mode.  Can
anyone explain why the choice was made to sacrifice the potential
sensitivity by giving up drift mode?

>   No, there are no reasons such objects would be missing
> from the TASS database, as long as they are bright enough to
> be detected in both the V and I passbands.  But you would
> have to go through the database to find them for yourself.

Are there one or more pages that point out how to access
the current database data?  (And is someone *really* keeping
all of the data online???).

Thanks for all the help.
Robert