[GreenKeys] Fwd: Re: FTGH Mite keyboard

[Duncan Brown]

Ethan,

Thanks for your description. It sounds like the M150 was similar to 
Mite's earlier (1960s) printers made for the military, still mostly 
mechanical. If you go to  NIck's site http://www.navy-radio.com/tty.htm 
and scroll down, you will find some of the MITEs used by the 
Navy/Marines. There should be some manuals there.  I think the keyboard 
& printing mechanism will be similar, however, they apparently replaced 
the motor in the M150 with solenoids, so there will be some differences, 
also.

The MITE printing mechanism is very similar to the M28. But don't get 
the idea that one copied the other.  We have a teleprinter made by the 
American Telegraph Typewriter Co. in 1908 at the AWA Museum that uses a 
similar system.

Have fun,

Duncan
K2OEQ



On 03-Nov-20 22:45, Ethan Blanton wrote:
> Duncan Brown wrote:
>> Someone on the list acquired the M150 last summer. Did you ever get it
>> working?
> That was me.  It "works" in that it (usually) can send loopback to
> itself when placed in local mode, but I have been unable to get any
> RS-232 out of it.  I had to table it due to work, but I hope to get
> back to it soon.
>
> Its keyboard is mechanical.  It has code bars underneath the key
> levers much like a Model 28.  When the keys are depressed, they engage
> beveled surfaces on the code bars at each key lever position to push
> the code bar left or right according to whether the bit in that
> position should be a mark or a space.  The code bars are plastic.  I
> do not immediately recall if I could see what the code bars engage to
> encode the bits.  It is certainly not a similar style of keyboard to
> the one that started this thread!
>
> The printing mechanism is quite interesting, and has a tape that runs
> between reels to move the print head mechanism back and forth across
> the page.  There are solenoids that actuate opposing tension wheels to
> shove the tape slightly right or left depending on the bit pattern
> that has been decoded, placing the appropriate portion of the print
> head at the printing position (behind the page, as I recall?).  This
> lateral adjustment plus a rotation to one of six faces selects the
> character, and a hammer strikes it onto the paper.  It seems like a
> clever mechanism, but (at least in my unit) sometimes it gets bound
> up.
>
> I'll get it all photographed and documented at some point in the
> hopefully not-far-distant future.  I have been unable to locate MITE
> documentation (which I would desperately like to have, to figure out
> how to get signals in and out of it!), although I do have a brochure
> that I will scan and make available, as well, at some point.
>
> As far as how long Mite was in business, I don't recall if I found any
> specific date codes this is almost certainly a
> 1970s design.  It has substantial electronics on printed circuit
> boards, including a modem with an audio coupler interface that accepts
> a WE Model 500 handset.
>
> I've attached a couple of photos.
>
> Ethan