[Boatanchors] D 104 microphone Question

[Al Parker]

Hi Greg,
    I suspect the head from the amplified base has a very weak cartridge
in it that the amp. is compensating for.  The head are interchangeable,
unless somebody has changed wiring on yours for some unkown reason.  Using
an amplified one on our boatanchors is really just for doing a little
impedance matching, not for amplification.  As you've found using an
un-amp one, additional output isn't needed if the cartridge is good.
Unfortunately, the crystal cartridges are prone to losing output as they
age, particularly if they've been in humid environments.
    It's too bad Astatic quit making cartridges, maybe Bob Heil oughta
make a "drop-in" - that would be well received I should think.
73,
Al, W8UT

----- Original Message ----- 
From: "Greg Mijal" <bluebirdtele@earthlink.net>
Subject: [Boatanchors] D 104 microphone Question
Hi:
I have a question concerning the D 104 microphone line.

I have an unamplified  D 104 and base.  It has plenty of audio going into
my SB 401 or Marauder (I like Heathkits).  I get good audio reports with
this set up.

I took the mic head off of an amplified base and tried it on my
unamplified base.
This arrangement hardly moves the meter in the transmitter and I have to
run the audio control all the way to end but still come up short level
wise.
 One thing I did notice is that the old unamplified head has the standard
Astatic black label on it.  The head from the amplified base has no label.
What's going on here?  I thought I could switch heads between any base and
head but apparently not.  Can someone give me some background information.
I sure would appreciate it.
Bill: This might explain what happened on the D 104 head you loaned me
recently.
73's
Greg
WA7LYO
in sunny Feenix