HI,
I have a Navico 6500 2 way VHF marine radio.
I have a duff microphone.
I have a six pin plug with a five round the edge and one in the centre configuration layout.
There are wires from the mike to pins 1,4 and 5.
The speaker goes between 1 and 5 (red and its screen)the white from the switch (tx,rx) goes to 4.
All the other pins are clear of solder but I have a blue wire from the handset switch, I assume it solders to one of the used pins.
Can you tell me if this is a common configuration and which pin the blue would solder to?
Your help would be very much appreciated. Thank you. Bob.
that is an old radio my friend… go get a new one 
Pin 1 is BLUE AND SCREEN
Pin 2 NOTHING
Pin 3 NOTHING
Pin 4 WHITE
Pin 5 RED