Call Search
     

New to Ham Radio?
My Profile

Community
Articles
Forums
News
Reviews
Friends Remembered
Strays
Survey Question

Operating
Contesting
DX Cluster Spots
Propagation

Resources
Calendar
Classifieds
Ham Exams
Ham Links
List Archives
News Articles
Product Reviews
QSL Managers

Site Info
eHam Help (FAQ)
Support the site
The eHam Team
Advertising Info
Vision Statement
About eHam.net

   Home   Help Search  
Pages: [1]   Go Down
  Print  
Author Topic: NEED HELP WITH ADDING FOOT SWITCH TO MIC  (Read 2535 times)
DARTICUS
Member

Posts: 28




Ignore
« on: April 27, 2013, 03:20:15 PM »

I'm trying to make a box with a 1/4 inch phone jack going in for mic and a 1/4
inch phone jack coming out the other side to the radio input. I have a foot
switch with a 1/4 inch jack to turn it on and off and want to plug it onto the
box to control on and off. I built the box and split the center mic wire to foot
switch to control on and off but all it seems to do is make it half volume. Do I
have to split both center and ground or maybe just the ground? I made the box with 3 jacks in it. Thanks Ron


Logged
AC5UP
Member

Posts: 3893




Ignore
« Reply #1 on: April 27, 2013, 04:35:43 PM »

Take a close look at the schematic for the microphone to see how the leaf switch is wired. On a typical radio (modern) they're double pole / double throw. One side shorts the mic element (mute) until the PTT is closed, then the mic opens up for TX. Some will also mute and un-mute the speaker. On the other side of the switch the center pole toggles between "enable RX" and "enable TX". In older radios with a T/R relay the normal state was RX until the PTT kicked the relay to TX. On electronically switched radios the PTT may always be needed to turn on TX or turn on RX.

If the radio won't play without the mic plugged in the PTT is muting the speaker as well as the mic element, or the radio wasn't designed to assume RX when the mic is "normally open".
Logged

Never change a password on a Friday                
DARTICUS
Member

Posts: 28




Ignore
« Reply #2 on: April 27, 2013, 04:49:33 PM »

Thanks but here is more info.
I was trying wrong. I was trying to shut down the mic at the mixer out but I think it has to be shut off at the radio plug by not sending a carrier. I'm running a shure mic 58, no switch, into a mixer which has a 2 wire main coming out. I do know my pin set up at the radio is pin 1 shield, pin 3 is transmit and 2 is audio pin 4 recieve. By shorting 1 and 3, at the radio, I throw a carrier. It looks like I need center out of mixer to go to pin 2 the ground to pin 1 and a second ground switchable, on off, with foot switch to go to pin 3. If this is right I need 3 wires coming out of my box which means one jack needs to go to let a 3 wire cable go to the radio 4 pin plug. Am I close??? Thanks Ron


Take a close look at the schematic for the microphone to see how the leaf switch is wired. On a typical radio (modern) they're double pole / double throw. One side shorts the mic element (mute) until the PTT is closed, then the mic opens up for TX. Some will also mute and un-mute the speaker. On the other side of the switch the center pole toggles between "enable RX" and "enable TX". In older radios with a T/R relay the normal state was RX until the PTT kicked the relay to TX. On electronically switched radios the PTT may always be needed to turn on TX or turn on RX.

If the radio won't play without the mic plugged in the PTT is muting the speaker as well as the mic element, or the radio wasn't designed to assume RX when the mic is "normally open".
Logged
AC5UP
Member

Posts: 3893




Ignore
« Reply #3 on: April 27, 2013, 06:23:21 PM »

What's the make & model of the radio?
Logged

Never change a password on a Friday                
DARTICUS
Member

Posts: 28




Ignore
« Reply #4 on: April 27, 2013, 06:54:51 PM »

This is a Galaxy dx 2547. Thanks Ron

What's the make & model of the radio?

Logged
AC5UP
Member

Posts: 3893




Ignore
« Reply #5 on: April 27, 2013, 07:16:41 PM »

Pin 1 is the shield on the mic cable (ground)
Pin 2 is audio +
Pin 3 is grounded for transmit
Pin 4 is grounded for receive

Here's the schematic for the stock mic.      Here's more than you ever wanted to know about the radio.

If you haven't tried for your Tech license yet, there isn't much to it.......
Logged

Never change a password on a Friday                
DARTICUS
Member

Posts: 28




Ignore
« Reply #6 on: April 28, 2013, 05:05:09 AM »

I have my tech ticket but not helping to get this wired. I like doing work on 11 meters before moving to amature frequencies. Thanks Ron

Pin 1 is the shield on the mic cable (ground)
Pin 2 is audio +
Pin 3 is grounded for transmit
Pin 4 is grounded for receive

Here's the schematic for the stock mic.      Here's more than you ever wanted to know about the radio.

If you haven't tried for your Tech license yet, there isn't much to it.......
Logged
DARTICUS
Member

Posts: 28




Ignore
« Reply #7 on: April 28, 2013, 10:37:06 AM »

Its working!
  I used 3 wires. On the radio I connected pin 1 to shield, pin 2 to audio, pin 3 to shield. I split 3 so the foot switch got between it. Seems to be working fine. I'm trying to get some studio mic sound using a mixer. Hope it improve the quality of sound. Thanks Ron
Logged
Pages: [1]   Go Up
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.11 | SMF © 2006-2009, Simple Machines LLC Valid XHTML 1.0! Valid CSS!