I have a plastic bird cage air mechanism (original from factory). It's
a really odd arrangement.  Maybe they have a small air supply unit
to adapt? Hobby shops have a battery unit to hookup to the feed hose.

I couldn't get the existing air pump to work -- used wrong materials.
What is a good material to rebuild the sound chamber? It's all plastic.
The rest is similar to a metal clock movement but well-made. I got the
[stamped metal] bird moving very well.

This is no doubt a lower grade example. The plastic whistle works.
It looks like there is room inside to hold a compact battery-operated
air supply. Photos:

1. Air pump on left has 3 chambers; two have touch levers [cam followers]
that alternate the cycles. The third chamber is ?? The whistle makes
sound if I manually apply air; it sounds not too bad.
https://www.mmdigest.com/Attachments/24/03/20/240320_155024_IMG_20240318_113950956.jpg
 

2. The bird waiting for it's sound [to begin]. The motion of this part
does work. German maker?
https://www.mmdigest.com/Attachments/24/03/20/240320_155024_VID_20240318_193758041_exported_27699.jpg
 

Paul Recupero
paulgansett@gmail.com.geentroep [delete ".geentroep" to reply]

[ Restorer Troy Duncan writes about pneumatic covering materials at
[ https://www.mmdigest.com/Archives/Digests/201811/2018.11.08.02.html 
[ and in this video he talks about the tiny pump and whistle:
[ https://www.youtube.com/watch?v=OP8sUSi41rk
 
[ -- Robbie