OT troubleshooting a SM57

[mat]

I was lucky enough to have an old not working Shure microphone for free. The exact model is ‘Shure SM57 Unidyne III dynamic’

There was two wires loose at the middle of the mic where it also opens. I tried to solder them either way but did not got the mic to work.

Could someone advice me how to troubleshoot this one ?

I found this http://www.shure.com/pdf/specsheets/spec_wiredmics/sm57.pdf but this one does not show what connets to the midlle pin on the center of the mic.

Here are few pics of the mic.

http://tinypic.com/51d9wl  

http://tinypic.com/51da2r

http://tinypic.com/51da46  

http://tinypic.com/51dbfb

http://tinypic.com/51dbgl  

http://tinypic.com/51dbhj  

mat

[birt]

i have one right here in front of me but the wire colors are different and it all goes into the goop in the handle you know. i can't see much of it.

but according to the pdf you should switch the red and blue wire on the xlr.

on the side of the capsule it should be green and yellow on the sides and (not shown in the pdf) black in the middle. if it doesn't work switch the wires on the sides.

if it doesn't work i think the capsule is broken or the transformer in the handle.

[niftydog]

first up you wanna be sure the capsule actually works before proceeding, otherwise you'll be wasting your time. Do you have an oscilloscope or access to one? You'll need to look for incredibly low level signals coming from the capsule as you tap the diaphragm.

[mat]

Hi,

but according to the pdf you should switch the red and blue wire on the xlr.

No, they are as in the pdf.

on the side of the capsule it should be green and yellow on the sides and (not shown in the pdf) black in the middle. if it doesn't work switch the wires on the sides.

The pdf shows the green and yellow wires ? Do You mean at the very end of the capsule ?

if it doesn't work i think the capsule is broken or the transformer in the handle.[/quote]

Maybe I'll have to take everything of from the case. Any idea how to remove the 'hat' on top of the mic ? It seems to be quite tight and I don't want to break it..

mat

[mat]

Hi,

first up you wanna be sure the capsule actually works before proceeding, otherwise you'll be wasting your time. Do you have an oscilloscope or access to one? You'll need to look for incredibly low level signals coming from the capsule as you tap the diaphragm.

We have an oscilloscope at work but have never used it   Should i put the probes on XLR pins 2 and 3 ? What about the scope settings ?

And again, how should the'hat' to be removed ?  :oops:

mat

[niftydog]

anyone at work who can show you how to use it?

If it doesn't work at all, probing the XLR won't get you anywhere.

Probe as close in the signal chain to the capsule as you can, that probably means the wires closest to the top.

You should be able to screw the wind-sock off and access the mic capsule directly... maybe!

Keep in mind that wires sometime break internally and that may be the cause of the problem.

[sean k]

Your basic dynamic mic is like a very small speaker and involves a coil of wire around former that has a magnet in the centre.The two wires,each end of the coil,are your signal wires and the earth goes to the case.Test it all with a DMM for continuity to find where the signal isn't but especially the two coming from the coil on the head...thats the actual noisemaker.