robert440 wrote:

The Silver Eagle version of the D104 has an amplifer (to work with modern
radios), so impedance is not an issue.
The mic does have a very high output (requires a 9V battery) that may easily
overload the mic input of a mixer, even with a pad engaged. There is a gain
control on the bottom of the mic.

Just for reference, where does info on the mic come from? Given the
built-in amplifier, it's obviously a recent version. Is it now
manufactured or sold by a company other than Astatic? I was surprised
not to find any data on the mic on the Astatic web sites other than a
mention in their company history article.

I'm familiar with the ham radio version of 50 years ago (which was
indeed a crystal element). It seems that while the basic model number
and appearance haven't changed significantly over the years, the inner
workings have evolved substantially.