A equipment for MicroVAX

kfield@J.BBN.COM.UUCP (07/11/86)

Does anyone know of A/D and D/A equipment available for
the MicroVAX II?  I need a hardware/software system that
will allow for 8 kHz sampling to and from disk.  (I'm working
with speech signals.)  I am familiar with the LPA-11K family of Unibus
peripherals;  I need a Q-bus version of this functionality.

-Ken

cetron%utah-cbd@UTAH-CS.ARPA.UUCP (07/12/86)

	DEC has recently announced (and then apparently never spoken
of it again) the VAXstation/RT or possibly the VAXlab....this is sort
of a combination of the A/D and D/A ... equipment from the MINC series
in a BA123 box...if you can get more info, you should be able to order
the other stuff directly...
	Also, Data Translation in Mass. makes a whole pile of stuff for
the q-bus (including almost all of the boards that DEC sells as their
own).. I'd quote parts and specs except my friend at DEC have borrowed
my catalog (hmmmm.....)
	As i recall, 8khz is very slow compared to the speeds that i recal
seeing - upwards of 25khz I think.....

-ed		cetron%utah-cbd@utah-cs.arpa
Computer Services Mgr
center for engineering design, univ. of utah

	(i have no connection with dec or data translation other than
having used 'both' companies equipment and found it top-notch...)

KFL%MX.LCS.MIT.EDU@MC.LCS.MIT.EDU.UUCP (07/13/86)

    From: cetron%utah-cbd@utah-cs.arpa (Ed Cetron)

    	As i recall, 8khz is very slow compared to the speeds that i recal
    seeing - upwards of 25khz I think.....

  It depends on what you are doing.  8 khz is too slow to digitize
voice or music.  You can only work with frequencies up to half the
sampling rate.  In practice, somewhat less.
  We have a 50 khz A/D and D/A board on an PC-DOS machine.  We used to
have a 40khz A/D board on a CP/M machine.  Either is sufficient for
audio signals.
  Video digitization requires several Mhz.  Seismic studies may require
only 10 hz.  Real time control may require anywhere from 1 hz to 1 Mhz.
The sampling rate you should choose depends entirely on what you want
to use it for.
								...Keith

cetron%utah-cbd@UTAH-CS.ARPA (Ed Cetron) (07/14/86)

	no, no, no,  I realize you need to match sampling
freq to source....(after 10 years doing it it is instinctive)
but i was talking about the specs of the boards that i was
recommending....
-ed