Hi All,

I picked this mic capsule up at an antique radio flea market a few weeks
ago.

http://mysite.verizon.net/vze2rfpz/id2.html

Can anyone ID this?

Thanks,

Mark Robinson

Mark Robinson wrote:

Hi All,

I picked this mic capsule up at an antique radio flea market a few weeks
ago.

http://mysite.verizon.net/vze2rfpz/id2.html

Can anyone ID this?

Thanks,

Mark Robinson

Carbon ?

JP Gerard wrote:
It's obviously a condenser capsule - a primitive one, too.

Could be anything from the 20s/30s.

My strong bet is that it's a homebrew capsule modelled after the condenser
mike design in QST magazine. The article is reprinted in the 1934 edition
of _Hints and Kinks for the Radio Amateur_.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

Hi All,

Thanks for all the comments so far. I looked at some of the older WE types
on the k-bay106 web site and didn't see anything that matched. I was
thinking it might be home brew as well. I'll have to look for the QST
reference. Can anybody scan a copy and send it my way? If it is a home
brew, someone had very good machining skills. I noticed that the hole
pattern on the backplate has a somewhat random pattern. I don't know if
this was done on purpose or just sloppy machining. I assume that these
holes were meant to form a resonator to aid in tuning the capsule. It also
appears to me that the diaphragm was tensioned by tightening the front
plate. Am I correct about this?

I'm interested in bring this back to life, but have some questions about
designing a tube impedance converter stage. I was looking at using some NOS
6021 submini tubes I have lying around. These are dual triodes. My concern
is that the recommended max grid resistance is 1.1 meg. It seems to me, I
need to use a much higher ( 100 meg) grid resistance. Am I correct about
this? Do I need to look at electrometer tubes like the CK5886?

Thanks for taking the time to help,

Mark

"JP Gerard" wrote in message
...
Hmmm, forgot a word there... how did that happen...

Meant "quite good" obviously...

JP

"JP Gerard" a écrit dans le message de
...
Looks quite for a homebrewed capsule, I was thinking about a WE or
something
like that...

Although I admit that the diaphragm looks pretty shiny...

JP