• You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.
  • Click here to find out how to win free radios from Retevis!

Shakesphere Fortress


just so you know, you've misspelled the manufacturers name. i only mention it in case that might be hindering your search efforts.


you might find an old mic wiring guide with this chassis in it, but you really dont need the info if you can figure out the wiring for yourself.

here's how:

first, determine of the radio is relay or electronically switched.
this is only if the radio is an old one like this is.
all radios made after the 70's are electronically switched.
if you hear receive audio from that radio with no mic attached, thats a dead giveaway that its relay switched.

if its relay switched, you only need three wires, audio transmit and ground.
if its electronically switched, then there will also be a receive wire.

to find out which is which, take the top cover off the radio so you can get at the main PC board.
with the radio off, set your DMM to "continuity" setting, and put one lead on any of the metal tuning cans in the radio. they are all connected to PC board ground.
now touch the other lead to each mic pin on the front of the radio until you find the one (or two) that has continuity.
this will be your ground pin.

now, turn the radio on.
using a short wire jumper, put one end to the ground pin you just found, and touch the other end to the other pins, noting what happens and drawing a diagram of the mic plug.
one pin will cause the radio to go into TX mode. this is your transmit pin.
one pin will probably cause a squeal, that is your audio pin.

if the radio is relay switched, then you are done, thats all you need.
if not, you need to find the pin, that when jumped to the ground pin causes the receive audio to be heard.
that will be your receive pin.

one way to determine which pins are the audio and ground pins is to look behind the mic plug in the radio.
the audio and ground pins will usually have a shielded cable coming from them that goes to the PC board.
center conductor will be audio, and the shield will be ground.

make sure you post the results after you find out whats what so that others can benefit from your knowledge.
LC
 
Taking LC's info one step further, to wire any microphone, if its a 4 wire mic, braid will be ground, one inside will be audio, set your DVM for continuity and attach one test lead to the braid,the other test lead to the other two wires, Rx wire willl show continuity without keying mic, tx will show it with the mic keyed.

You then match the wire after noting what's what and use LC's info to put same wire to same pin.

If its a 5 wire microphone chances are braid is ground,audio is inside itn leaving you 3 wires, two will show continuity with microphone unkeyed, one of those is switch common ground the other RX,

Try both wires to the last wire and the one that shows continuity with microphone keyed is TX

You then solder switch common to the same pin Braid/Ground on radio that Braid went to, good idea to twist it and braid and tin them together before hand, tin all wires and all microphone receptacles and you'll get a much neater job,

using a vice to hold plug is a very good idea as you will need one hand for iron, one to hold wires or if you haven't got asbestos fingers like me tweezers to hold wire in position as solder solidifies, nice shiney finished joint your looking for, preheat the receptacle before bringing tinned wire to it and it will be ready to go in seconds, extra solder comes to receptacle or iron, not iron to solder, a small tip size is advantageous in doing microphone plugs as its less likely to damage surrounding plastic insulator and wires a receptacles on plug thin and quick to heat.

good idea to use a 15-25w Iron and 60/40 solder, preferably Ersin Multicore or similar quality, preparation makes perfection.



One way to find the ground pin on radio without even opening it is to attach one test probe to negative lead of radio whilst unplugged from psu/battery and probe the 4 or 5 pins in the radio for continuity,the pin/s that show it are at board ground.

LC's just too keen to get inside there and work some magic, lol ;)

If you want to do six/eight pin radios, the stage after finding the radio ground pin is to set your DVM To volts range of over 15v, 20 or 30 ranges is common, connect the black lead to ground (you can use psu black post or radio ground pin and probe pins with red lead looking for voltages around 5v to 13.2 or 13.8 range, pins with the 5v are almost always for up or down.

Pin with 13v range can be used to power speech processors, power mikes with dropper resistor and zener etc, but whatever you do do not probed it with a bare wire or even an insulated one as it will short circuit radio, and depending if you hit ground it can blow fuse, lift tracks if right fuse ain't fitted, shorting it too other pins can blow microprocesser, only a voltmeter set to volts can bridge this pin with ground.

If your not experienced I suggest you master takin on 4 pin mics before messing with 5,6 or 8 pin radios, its very easy to damage them.
 

dxChat
Help Users
  • No one is chatting at the moment.
  • dxBot:
    Greg T has left the room.
  • @ BJ radionut:
    EVAN/Crawdad :love: ...runna pile-up on 6m SSB(y) W4AXW in the air
    +1
  • @ Crawdad:
    One of the few times my tiny station gets heard on 6m!:D
  • @ Galanary:
    anyone out here familiar with the Icom IC-7300 mods