My Autopiano-based Recordo was done up in 1986.  It now needs some
work.  I also now have a variety of A, B, and C type Recordo rolls.
The types are those according to Bob Billings' article.  Can any of
the MMDers help me with some information, please:

1. Is there any dimensional information for the original H.C. Bay
expression box and the pneumatics therein?

2. Is there any patent numbers for anything Recordo?

3. Is there any photos of Recordo expression boxes?  I have one photo,
from John Tuttle's website, which could be a type A box _or_ a type C
expression box.  In the photo there appears to be a limit adjusting
screw to prevent full closure of the regulator pneumatic.  Is this
correct?  The picture looks very much like it has 'Autopiano' stamped
all over it.

4. Did Bob Billings (or anybody) ever get the Recordo type C expression
mechanism from Australia or anywhere else?  If so, is there any
measurement data and/or dimensions or pictures or sketches for it?

5. In the H. C. Bay type A expression box, is the choker arrangement
a knife valve or is it a flap type of valve as shown in the drawing in
Bob Billings' paper, "Recordo Banner Flies again"?

6. I have some QRS Recordo rolls with a M xxxx number.  Are these rolls
always type A rolls?

7. I have many QRS Recordo rolls with the M xxxxx and the M xxxxxx
number system, and I presume these are type B rolls.  Is this correct?

8. I have QRS Recordo rolls which have an A 611xxx, A 612xxx, and
A 613xxx numbering system.  Are all of these type C rolls?

Here's hoping I can get answers to all these questions; so thanks in
advance.

Paul Rumpf
Melbourne, Australia