[ARC5] Re-working T-17 mics (was: M-15 type microphone)

[hwhall at compuserve.com]

Here's the fellow from whom I obtained the N-1 type carbon element:
Steve Hilsz <jydsk at tds.net>
He has a website here
http://phonesurplus.com/


 One element was marked "Roanwell 10258 RN-1H" and another marked "N-1 3656".

 

 There's also a place here
http://www.audiosears.com/products/data/mics/
that has a selection of carbon mike elements and some data on them but it looks like you have to ask to get prices.

To fit the N-1 into the T-17 casing I made two wooden washers from 3/16 inch basswood from the local hobby store. Both washers were 1.75 inch outside dia. One was 1.28 inch inside dia and the other 1.1 inch inside dia. When the two were stacked together they made a snug fit inside the T-17 and the N-1 fit snugly inside the washers. The T-17 wires can be tack-soldered onto the rings of the element at its back. The adapter could have been turned with a lathe from one chunk of wood but I don't have a lathe.

I'm presently tinkering with a T-100 element from the local surplus store that I may be able to make work in the T-17. It will drop into the T-17 mike body okay, but not with the original insulation/spacing ring (like a length of non-sticky plastic tape) in place. I'm not even sure that ring is necessary, it seems to only isolate the element from the mike body, but I'm just about to look for some really thin material to isolate the element from the mike body. Alternatively, I've stripped the outer crimp ring from a T-100 and it will fit with the plastic isolation ring in place but the T-100 will need something to hold the parts together - I think a fat O-ring may do it once the mike is buttoned back up.

Wayne
WB4OGM
 

 

 

-----Original Message-----
From: DSP3 <jeepp at comcast.net>
To: hwhall <hwhall at compuserve.com>; arc5 <arc5 at mailman.qth.net>
Sent: Thu, Nov 6, 2014 4:15 pm
Subject: Re: [ARC5] Re-working T-17 mics (was:  M-15 type microphone)



Does anyone know of a source of these N-1 carbon elements?

Jeep - K3HVG