17 Jun
2011
17 Jun
'11
2:21 p.m.
Thanks Peter, Doug and Alexey
I know which hypothesis is the correct one now. It was MESS., rather than a
problem with my machine.
ARGH!!!. I could make some comment about 'yet again the classic computer
is not the problem' :-)
[...]
HOWEVER, I could have saved myself all this trouble if
I'd checked the MESS
Sound Properties first. Not the sound card but the sound configuration in
MESS itself. The sampling rate was set at 48000 (Duh!). You were on to it
Alexey. Thanks for mentioning that or I might not have thought to check it
(MESS has a HUGE number of configurable properties).
Fortunately, with real tape recorders you can check the tpae speed using
a stroboscope if you have to (meaure the diameeter of the capastan using
a micrometer, measure the rotational speed by making the flywheel and
strobing it, calcualte the tpe speed in the obviosu way).
I hve found that white LEDs are an ideal light source for stroboscopes,
and you can easily disng the circuitry to provide a short light pulse
with a much longer gap between them which gives a clearer indication of
the strobe markings.
Some time back I built a pair of such strobes. One has an adjustable
oscillator, switchable divider chain, and am output (1:1 mark-space
ratio) at the flaching frequency to drive a frequency coutner. The other
is crystal-controlled and gneerates 100 or 112 flahses per second to
simulate a mains light source in Europe or the States. I find that gives
am uch clearer indication for things like floppy drive speed strobe disks
than a mains light bulb does.
-tony