On Friday, October 11, 2019 at 2:07:11 PM UTC-4, Tango Eight wrote:
I don't think it's a netto leak. I've made a few of those.
IIRC the tube ended up about 3.5 - 4" long, 0.012" ID.

I think you're right, trying to recall last time I saw one decades ago...
Don't know why a restrictor would be that long though.

Side note: modern pressure transducer based electronic varios like to be
on pneumatic circuits without leaks, without large capacities and without
any flows to speak of. Sharing a TE probe with one (and only one)
mechanical vario may be done with reduced performance of the electronic
vario. Sharing static with any mechanical instrument generally goes bad,
don't do it. Sharing the pitot with one ASI can be done in a pinch,
it is the least critical of the three.

Any mechanicals on pitot, static or TE will definitely upset the SN10C...