I remember them. Their equipment modifications were
pretty good. They did have some kind of business-related problem
and I remember reading about a fire that destroyed a wear house
full of products, etc, so I am not sure if they exist today or
not, but whether or not they do, here's the problem and within
that problem is also the solution.

	As one who likes to build and tinker with stuff, I can
tell you that the kind of stuff that Science Products used to
put ports on just doesn't exist any more. I bought a used DVM in
the early eighties that I had the intention of making talk by
tapping in to the display lines that fed the digits in the
display. It would have been possible and this is the kind of
device that Science Products would have been modifying back
then.

	The display was on a board with the 7-segment LED chips
right there where one could solder ribbon cable to the back of
each chip or remove the chips and replace them with 16-pin DIP
headers if one wanted to sacrifice the display. One could have
then taken the 8 segment leads which were actually 7 segments
and a decimal point, anded that with the strobe which activated
each digit, and fed those leads to logic circuits or a
microprocessor to decode each actual digit. This could have all
been done in the eighties and while the result would have been a
little awkward, one could have had a talking DVM or a DVM that
sent CW.

	"QST" even had articles about how to modify DVM's and
frequency counters to make them accessible.

	It is all very different now in that the level of
integration in common electronic devices is so much greater than
in the Science Products era. You simply can't get to the display
drivers without totally destroying everything. Open up something
today and you may see a monster surface-mount IC that is the
whole device. The rest of the board is possibly hundreds of
traces going to the LCD display screen. You could have 500 or
600 columns and another 500 or 600 rows to address each pixel on
the screen to make it possible to generate graphics, words and
numbers, and even whole pictures.

	I am not trying to be negative or explain why this or
that can't be done, but today, it must be done differently. You
just can't run 20 wires out from the display board any longer
and read the display. If there is a signal to read, it may be a
serial data channel consisting of a clock line plus at least one
more wire that goes high and low according to bits being sent
and received. You really need some kind of processor to decode
those data and that is a possibility, but the whole level of
complexity is way up there compared with how things used to be.

	In some ways, the possibilities are greater now but the
techniques for getting at the data are totally different now.
By the way, I was lazy and never got around to building that DVM
interface. I had one of the analog DC volt meters that AFB, I
think, sold in the early seventies that used a Wheatstone Bridge
and chopper modulator so I could read DC voltages and
resistances. I fooled around and procrastinated until the early
nineties when the Radio Shack Talking DMM came out and I just
never got around to finishing that project.

Martin

Tom Brennan writes:
> Actually, I wasn't even thinking about a computer.  In fact, ten or 
> twenty years
> ago there was a move toward one of these systems as a universal access 
> tool.  It
> wouldn't be much more than a speech synthesizer.  There used to be an 
> outfit
> called Science for the Blind which became Science Products who would add 
> speech
> output to any digital device that you had by just adding a port and 
> supplying
> you with a voice box.