D 104 microphone elements

[Grant Youngman]

> I have several D 104 microphones and some sound better than others. One
> of them once utilized a pre-amp that someone took out of the circuit by
> by-passing it. It sounds very poor and has very low output. My question
> is whether anyone has any reliable information whether ALL Astatic D104
> microphone elements are the same or whether those microphones with
> pre-amps get a different element.

There is no difference in the elements between preamped and non-
preamped D-104s.

D-104 crystal elements do go bad over time -- from heat and humidity
mostly.  The typical hamfest D-104, that has been riding in the rear
window of somebodies car, or sitting on the hood of a pickup in the hot
sun all day waiting to be sold, is well .. potentially going to be fried.  Output
drops, and frequency response goes to pot.

New elements are available from Amateur Electronic Supply (and probably
others) for about $20.  There are two types -- crystal and ceramic.  The
ceramic are more resistant to heat and humidity, but do not have the nice
frequency response of the crystal element.  If the mic is used and stored
in a normal household environment, the crystal element is a much better
choice, IMHO.

Grant
------------------------
Grant Youngman / NQ5T
nq5t at home.com
http://www.globeking.com
Double Oak, TX -- nr Dallas