12 Aug
2016
12 Aug
'16
12:55 p.m.
On 8/12/16 10:14 AM, emanuel stiebler wrote:
I would be happy just to get this one running. I'm not too keen on digging for more
head stacks right now.
On 2016-08-12 10:27, Al Kossow wrote:
had to dig up my notes from 2013
the drive I have is 18 track (3480 head) with 18 NE5592D differential amps
the A/D is a AD7322 2 channel 12 bit 1msample
I have no idea what the actual sample rate used is
and I can't really tell from the picture in the presentation
physical is a .1 grid of square pins coming off
of a flex cable to the head stack.
electrical is you supply a bias current and directly read magnetic flux with an opamp
OK,
I traced all of that out the last time I made a
run at this windmill. John used an FPGA
development board with an 18 channel A/D, which also controlled modified firmware on the
motor driver
and digitizes the tach pulse to get actual tape speed.
18/36 channels? Which sample rate? Resolution?
MANY years
ago, I bought a dozen 3480s in Chicago and stripped them for the heads at my parent's
farm in Wisconsin, so I could try grafting one onto another transport if I had to.
I've been unsuccessfully
trying for years to get the schematics for a 9914 or 9914V (they aren't inlcuded in
the service manual).
So, going for the 36 track heads too?