Highfields Amateur Radio Club
Constructors Corner.

I've labelled this project as moderate (orange) because it uses a modular plug, therefore requiring the use of specialised crimping pliers, otherwise it would have been easy (green).

This adapter allows the use of 8 Pin round Alinco microphones on many Alinco radios with the 8P8C modular socket. The image below shows the view of the 8P8C plug with the locking tab underneath and wire connectors toward you. The 8 Pin round socket is viewed looking into it as if you were about to put a plug in it.

Parts

8P8C modular plug.
8 pin round line socket (locking ring type)
7 core cable to suit.

Method

1 Making a note of the order of the colours, crimp the modular plug onto the cable.
2 Cut the cable to the required length (if not already).
3 Slide the line socket body onto the cable.
4 Strip and tin the free end of the cable.
5 Using the notes made in step 1 and referring to the table below, solder the wires to the correct pins on the line socket.
6 Assemble the line socket once connections have been checked and whiskers have been removed.

8 pin Modular Plug	Pin	Signal	Pin	8 pin Round Socket
	1	+5V	5
	2	Frequency Down	3
	3	No Connection	6
	4	PTT	2
	5	Mic Ground	7
	6	Mic Audio	1
	7	Ground (PTT and other functions)	8
	8	Frequency Up	4