[ARC5] Carbon cartridge replacement circuit

[Brian Clarke]

Do not attempt to measure the resistance of a dynamic microphone element – you may burn out the voice coil. As you are unsure what kind or microphone you have, best not to measure resistance at all until you are sure. A carbon microphone is unlikely to be damaged by resistance measurement attempts; if you are sure it is carbon, then shake the microphone while measuring resistance – it should change; if it does not change, it is possible the carbon granules have clumped together. Then you can use the (country name) postal worker test method to try to free up the granules.

 

73 de Brian, VK2GCE.

 

On Friday, 28 April 2017 3:52 AM, Roy said:

 

J,

 

I have more than one microphone used in Navy planes (helicopters) in the 60's and 70's.  I am not sure if these are carbon microphones or dynamic ones (we did use little inline amlifiers at about that time with some of the lip mikes we had.)

 

Can you give any hints as to how to determine which is which?  Resistance maybe? One is gray and another one or two are black.  They mounted on the helmets.

 

Oh yes, I will look on them for some sort of nomenclature - I bet I'll find something.

 

Roy

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