Need info about old Choir Mics

As near as we can figure these, mics are at least 50 years old.
The mic tubes are hollow "wave guides" with the pick-ups in the base.
As you can tell from the photos, they are nearly identical, made in Germany,
one has "ESL" on it and the other has a 'flying' "S" on it.
Take a look, there are six pics , each almost 500 K , so
if you are using a dial-up, this site may be slow loading.

http://alkoran.org/choir_mics/

Any info about these would be appreciated
Thank You

Don Ritchie, Euclid Ohio

Hi - Why are you looking for info on the mics, can I ask? Do they need repair? or are you trying to buy or sell them?

I am looking for info because they are old.
We use them and are getting RFI, (PLEASE don't tell me how to fix the RFI)
We MAY be looking to sell them, but can't do much until we know what they are.

Thanks

Don