An automat franking is not the same thing as a meter mark franking. With an automat you put in your money and the machine then franks your letter. It is then ready for the mail box. The cover below shows what I take to be an example of this kind of automat franking:
Click on Images to Magnify
I have never seen anything like this before. Can any of my readers help?
The dates on all the postmarks are compatible with the automat date of 2 8 38 and the 5 kopecks would have to be a local tariff. The cancels on the reverse are all a bit exotic: the roller cancel reads LENINSKI UZEL and the two double ring cancels read FRUNZENSKI and FRUNZESNKI UZEL (My dictionary gives "junction" and "centre" for UZEL)
I would guess that this is a philatelist's letter - it's partly the very careful handwriting which makes me think this and partly the fact that the letter has been opened at the bottom, not the top (leaving the meter mark neatly framed by the unopened top of the envelope). But I may be wrong.
Automats are things which go Out of Order. I cannot imagine that Moscow's AUTOMAT No. 1 was in use for very long. But did it even exist? Answers please!
the stamp automat cover is really, really cool! I like it very much.
I found some information in the "International postage meter stamp catalogue": http://en.wikibooks.org/wiki/International_Postage_Meter_Stamp_Catalog/Union_Of_Soviet_Socialist_Republics
"This stamp was generated by an automat machine used for three days during the Exhibition of Socialist Communications in Moscow in 1938.
Only one example is known to survive."
The pic in the catalogue has a different value. But your copy is of much better quality. Congratulations!