[TenTec] Microphones

[Stuart Rohre]

Bill, you might ask if anyone at Ten Tec is knowledgeable about the 
Electro Voice microphone, as Ten Tec was founded by EV's officers.

The 638 was probably a high impedance mike; I recognize the number, but 
can't recall if it had switching or a pin change on the connector to 
pick high or low impedance.

Most newer ham rigs are set up for low impedance say 600 ohms electret 
mike elements.  Check your specs.

A replacement cartridge, if the 638 one is not of dual impedance by 
selection of the right pin on the jack, can be obtained.

Heil makes mike elements for DX or rag chewing, which while modern 
elements are tailored to voice use.  The DX element is said to have more 
"punch".  Ten Tec may know who supplies Electro Voice parts now.
But also, Shure Inc. in the midwest, still makes mikes and supplies many 
elements compatible with older dynamic mikes.  They may have something 
that will fit the Electro Voice.

I went to look just now for a 638 I thought we had out back in a lab, 
but it was not there. But here are my thoughts on getting into various 
types of mike bodies:

If you don't find a small screw(s) to detach the front of the mike, 
perhaps the ring is threaded and will unscrew.  Other means were used 
with some mike bodies.  Something like unscrewing the screw holding the 
connector on the back end might release a kind of bracket holding the 
connector and the wiring plus, at the front, the mike element.

GL,
Stuart Rohre
K5KVH