Odd floppy drives (Helitron)

[Tony Duell]

> 
> 
> > On Sat, 24 Sep 2005, Scott Stevens wrote:
> > > The oddest 'floppy' drive that I ever saw was a dictaphone machine that
> > > recorded by cutting helical audio tracks like a phonograph record on a
> > > thin 'floppy' plastic disk.  Ooops, it wasn't digital (unless you held
> > > it in your fingers).
> > 
> 
> ... that would be (or describes) the Gray 'Audograph', made by Northern
> Electric (at least in Canada, perhaps by Western Electric in the US).

Somewhere I have a similar dictating machine made by (badged?) Olympia 
IIRC. I've not got any disks for it, but it's obviuos from the design, 
that the disk had a groove in it to guide the magnetic head. 

There's a slot in the front where you slide the disk in. It goes onto a 
turntable. There's an arm, a bit like the tone arm of a record player 
that carries the head, and which can be moved by a lever on the front. 
When it's locked in the rest position, it lifts the disk clamp off the 
turntable so that the disk can be inserted or removed. 

A couple of solenoids engagee either a slow forward drive (record/play) 
or a fast reverse drive ('rewind'). A button on the front engages the 
fast drive and lowers a magnet onto the disk for 'bulk erase'. 

Most of the functions are remote cotnroller. The microphone has a 4 
postion slide switch (record, stop, play, rewind in that order IIRC). 
Playback is either through the (moving coil) microphone transducer or via 
a little speaker in the unit. There was also a footswitch that had pedals 
for rewind and play, presumably for transcribing the recoridng on a 
typewriter. You could also obviously connect headphones, I don't have 
them.

One odd feature is that the 2-valve amplifier has a tone control. I can't 
really see the point...


-tony