Microphone Requirements
a) Delta and Rangr Conversions
To convert one of the Delta or Rangr radios, you really need the transistorized dynamic microphone
used with the radio in commercial service. They can often be
found on eBay auctions, or perhaps even from a friendly dealer.
They are designed to be 'line powered' by the radio (+ 9 VDC on the Mike High lead) and provide
enough audio to traverse the long cable nornally associated with trunk
installations.
As you are probably going to
build your own 'custom' control head, there's no way that the factory
plug on the end of the mike cable can be used with your new head.
So, just cut it off as close to the plug as you can.
Then, use a razor blade to skin back about 2 inches from the coard and
remove the rigid rubber cable that keeps the cable in shape. In
so doing, you'll discover 5 color-coded leads, red, white, green, black
and blue.
Connect the white lead to the mike
PTT and the black and green leads to ground. Connect the red lead
to the 'mike hot' portion of the 3 conductor plug. That's all
there is to it. The blue lead does nothing (that I could find).
When the wiring is finished, make an ohm meter check. When the
PTT switch is depressed, the resistance between the mike hot lead and
ground should be about 4.25 K ohms. Of course, the resistance
between the PTT switch and ground should be near zero.
Crimp the end of the plug so that the cable will not pull out. If
needed, apply hot glue to permamently fix the connections.
b) Phoenix Conversions
The GE Phoenix radios use an electret mike, again powered by the radio.
If you are going to retain the existing connection method in the
rear of the radio, then there's no need to make any wiring changes.
If, however, you wish to mount the microphone connector on your control
head (along with the Phoenix volume control), then the black and shield
lines from the mike are connected to the ground connection on the plug,
the white lead is the PTT and the yellow lead is the Mike High. Of course, you first have to cut off the connector.
G.E.and
the product names Phoenix, Delta, Rangr are trademarks of Ericsson General Electric Mobile
Communications
DISCLAIMER - - If you follow the steps
outlined herein, you do so at your own risk.
I cannot, nor will not, be responsible for any possible damage to radio
equipment, personal property, to yourself or to others caused by
modifications that you may make to the radio as a result of your
reading this.
The M/P controls TRANSMITTING and receiving
on a wide range of frequencies. In the USA, TRANSMIT operation requires
a license issued by the
FCC for the class of operation
intended. Amateur radio licensees must maintain strict
control over their equipment, preventing unlicensed
operation within the amateur
bands, or outside of them.
The
information on this website, the schematic drawings and the secure code
contained within the microprocessor are all copyrighted.