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Old 19th Mar 2011, 5:54 pm   #1
chunkycublondon
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Default Quiet microphone on 332 - What else should I try?

Basically, I've started restoring old telephones as a hobby lately and I've been working on a couple of 332 telephones, both of which either have no sound in the earpiece, or substantially less than in other similar phones I own. I've tried pretty much everything - cleaning all the contacts, changing the handset cables, different handsets, etc. What else could it be? Could it be the induction coils causing problems? Or do I just have two phones with two duff handsets? Your advice would be much appreciated.
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Old 19th Mar 2011, 6:32 pm   #2
russell_w_b
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Default Re: Quiet microphone on 332 - What else should I try?

Your carbon mic inserts are probably wanting - some are better than others, some have been kept drier than others, etc...

There are electronic replacements if you wish to bring the sound levels up to modern standards, but the carbon inserts can be revived, sometimes. It's unlikely to be the induction coils.

Have you cleaned all the dial contacts? Not just the pulsing contacts, but the dial-off-normal contacts as well?
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Old 19th Mar 2011, 9:19 pm   #3
Dave Moll
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Default Re: Quiet microphone on 332 - What else should I try?

You say that you have tried different handsets, but have you confirmed that they work with a known good 'phone? Though, I infer from your opening sentence that these two may be the only suitable 'phone that you have - so far.

As Russell says, the problem probably lies with the carbon inserts. It may be worth taking them out and giving them a few firm raps against a solid surface to shake up the carbon granules, as they can become caked over prolonged periods of non-use.
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Old 23rd Mar 2011, 10:19 pm   #4
chunkycublondon
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Default Re: Quiet microphone on 332 - What else should I try?

Thanks for this! It turned out to be the dial contacts after all, after three or four late nights (!) checking each and every single bit of wiring in both phones, cleaning all the contacts inside and other stuff.
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