16 May
2024
16 May
'24
4:02 p.m.
I know the document on bitsavers, but the series 700 is a complete different one.
In this reader there is no clamp or breake or similar things, but a stepper motor which
drives two
sprocket wheels. Between the wheels is the optical sensor.
In the moment I'm about to reverse engineer the board. The db25 connector at the back
is almost
completely populated. I would like to known what the pin are for. Very good, that Decitek
still
exists. I will write them.
Micha
Martin Bishop via cctalk wrote:
It looks as though Decitek remain in business
http://www.decitek.com/index.html
Scan of a series 700 reader manual on bitsavers http://www.bitsavers.org/pdf/decitek/
On an optical reader, I would not recon the capstan running at power on as unusual - a
pinch roller which engages for drive and a tape clamp engaging for stop motion are both
common features. For simple single byte read operations, probably the paradigm used when
the unit was built, it is not uncommon for the sprocket hole to stop feed and energise
clamp. The circuitry to control this behaviour may be in the drive or controller or
shared; and then there are configuration links / switches ...
An empirical approach is to scope / LA the sprocket and data bit outputs; ideally with a
tape loop.
HtH; Martin