[GreenKeys] saga of the spring...

[Roy Morgan]

>   So I took the spring off, removed about 3 loops, bent up one remaining 
> loop to mount with and put it back on....  Seems now, whenever I receive 
> FIGS (or type FIGS) I hear a pretty big clunk as it shifts into figs mode.  ...
>Any thoughts on this one?

Eugene,

(Based on *very* little experience with the M-28):

You may still have an unbalance in that gizmo, so it is pulling harder or 
sooner or faster in one direction than the other.

(I assume that if you remove your newly installed/modified spring, the 
KLUNK goes away.)

Detailed Teletype Corp instructions for machine adjustments often include 
measuring the spring tension in specific positions/extensions.  Little 
force gauges were used to check the pull or push needed.  I suggest you 
either get a PAIR of correct springs and install them, or measure the pull 
your springs are putting on the mechanism.

One thing you might try is to decrease the pull on the new spring by making 
a little ring or loop of wire to let it operate in a less extended position.

I await further reports, and offer Morgan's Law of Inverse Perversity in 
both original form and a modified form to apply to this situation:

Morgan's Law of Inverse Perversity

If you have no spare for a critical part, that part will fail at the most 
inopportune time.  If you do have a spare, or spares, the original one will 
never fail and you'll never use the spare.

Morgan's Law of Inverse Perversity - Troubleshooting Corollary:

If you have no information on an obscure failure mode, that failure will 
happen to you at the most inopportune time.  If you do have complete, 
detailed information, the system will never fail in that way.

Note:

Car mechanics of the past would get a three foot stick and put one end 
against various parts in a running engine and the other end against their 
ear to find the noisy, failing bearing or whatever.  (DO NOT DO THIS!)

To adapt this dangerous method to teletypes, get a little microphone, 
amplifier and sound-excluding earphones. Move the mike around the machine 
on the end of a wooden dowel to locate the suspicious noise.

Those fortunate enough to have a stroboscope such as the GR Strobotac, will 
find a running teletype machine to be the source of nearly endless 
fascinating investigations.  The trick is in the triggering!

Don't let this thing beat you. It's "just a mechanism"!

Roy



- Roy Morgan, K1LKY since 1959 - Keep 'em Glowing!
7130 Panorama Drive, Derwood MD 20855
Home: 301-330-8828 Cell 301-928-7794
Work: Voice: 301-975-3254,  Fax: 301-948-6213
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