Motorola Microphone - crackling when press PTT

[g8tzl2004]

I have a HMN1080A microphone from an Astro Spectra/XTL radio.

The mic works OK but I have to avoid any slight "wobble" when I press in the PTT otherwise there is a bad rustling/ crackling noise TX'ed on my signal.

I have another HMN1080A which works perfect with no rustling noise when I press the PTT.

I'm guessing that its a problem with dirty contacts on the PTT switching. If I open the mic and apply some switch cleaner will the problem will be solved?

Any ideas?

Thanks

[Bigred]

Common. Don't know how many guys replaced the switch, but I found it just as quick to clean them. Never seen any just plain wore out.

You can hose the switch down with contact cleaner whilst exercising it and that will cure your ills. I however like to disassemble it and give it a good cleaning for best life. Take off the "C" clamp making sure the spring doesn't fly off, remove spring and plastic collar. Push plunger out the back of the switch noting how the contact fingers go in. You might have to push a cap over to get the plunger out. Swap the switch body with a q-tip and cleaner real well. Clean the OEM grease off of the contact fingers and burnish them bright, lightly with a scotch brite pad. Add just a light swipe on silicon on the contacts. Put the contacts back in the plunger and hold the with your fingers as you push the plunger back into the switch. Finish reassemble.

The switches with the red plungers are beefy and easy to do. On the white plungers the contacts are a little more whimpy and can be bent easily, which you don't want to do.

I've done plenty, don't get call backs for scratchy mics, and keeps the masses happy.

[g8tzl2004]

Bigred - many thanks for the excellent advise - its much appreciated.

[jackhackett]

I use a pencil eraser on the contacts.

[Will]

Craig Pro Gold....