Telex Repair

At my school's auditorium, we use a telex intercom system for tech communications (model number BP-1000). On one of the six headsets, the microphone took a dump (and I found this out the hard way too, i was running lights and couldn't talk to the spotlight operators for the whole show.. good thing they went to rehearsal). I ruled out the posability of the beltpack being the problem by trying the headset on another pack. You can hear everyone else just fine, so i doubt the cable on the headset is the problem.

So my question is, can i replace the microphone in the head set with a Mic from Radioshack (like this)? Thanks in advance.
 
what kind of headsets are you using?... also it may be a faulty solder joint on the mic and just need a re-solder... or it may be a faulty joint on the XLR
 
It's probably broken right inside, or just past, the connector. Take the connector apart; there will be four wires going places. If it's like RTS wiring, the microphone pin is 2, I believe. If all the wires are still attached, then it's probably a break in the cable just a few inches back of the connector. If it's a broken joint ("high impedance air gap"), simply resolder it to the pin it came from. If not, try cutting the cable back a few inches before the connector and rebuilding it.

Failing that, then it could be in the headset itself. A PH-1 is easy enough to find...
 
I'll try that next time i'm in there. Hopefuly it can be repaired, they don't look that cheap to replace..

Thanks guys
 
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Often the wires in the headset will break inside the knuckle where the microphone is connected to the ear piece. Sometimes you need to pop out the speaker, and check the solder joints under that knuckle. If you abosoloutely have o replace the mic I think that one will work, but I doubt it's the mic element itself that needs to be replaced.
 
Almost every time I have a problem with a headset, its a broken solder joint in the connector. It's very rare that I have a different problem. The up side here is that connectors are very easy to fix. If you're having trouble with which wire goes to which pin, take apart the connector on a headset of the same model that you know is good, and make the one you're working on look like that.
 
I was in the auditorium today and got a chance to mess with it. I pulled the connector apart and everything seems to be connected. I couldn't go tearing into the rest of it though, because we needed to use it for "Joseph". Hopefully i'll have more time to look into it after teardown sunday.
 
In the dozens of headsets I have fixed, I disagree that a dead solder jopint is most common. In a great majority of cases, a cable fails, either the one between the headset and beltpack or one of the ones on the mic boom. Normally failure is at or very close to a flex point. Delibrate flexing tends to allow you to work out where the failure is and then you can look to fixing it...
 
The Radio Shack mic you linked to isn't going to do what you want. Aside from the physical differences, it's an electret (condensor) type while headset mics are typically dynamic. My quick and lazy searching didn't come up with details on the PH-1, but the PH-100 (presumably just a newer version) is definitely dynamic.

As others have said: the best thing to look for is a broken wire or solder joint either at the connector, or where the mic boom pivots. Things tend to break where they're stressed.
 
I just fixed 4 headsets with broken mics on Friday, all 4 were broken solder joints in the XLR Connector where it connects to the beltpack. Try there first, it's an easy fix just re-solder the wire that has ether come off or looks corroded. I highly doubt there is a problem inside the headset itself, it's almost always in the XLR Connector.
 

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