[sdiy] (Semi-OT) cap polarity in microphone

[Scott Gravenhorst]

I'm curious, why wouldn't measuring the DC across
the cap terminals tell you?

harrybissell at prodigy.net wrote:
>If the bias on the preamp side of the cap is higher than
>the mic bias voltage... its correct.
>
>If not it is an assembly error. Measure the DC on both sides
>with respect to ground, and decide...
>
>H^) harry
>
>
>>From: Ingo Debus <debus at cityweb.de>
>>To: synth-diy at dropmix.xs4all.nl
>>Subject: [sdiy] (Semi-OT) cap polarity in microphone
>>Date: Mon, 18 Mar 2002 11:02:21 +0100
>>
>>Hi,
>>
>>out of curiousity I had a look into my cheap (about $50) stereo electret
>>condensor mic. Not much in there, two capsules with two wires each,
>>powered via 6.8k resistors from a 1.5V battery, and two 10uF 25V
>>electrolytic caps in the signal paths. But the funny thing is, minus of
>>the caps is connected to the capsule side, where the plus of the power
>>supply is connected (through the 6.8k resistor). That's backwards,
>>correct? Is there a specific reason for that, or is this an assembly error?
>>
>>Ingo
>>
>
>
>
>
>_________________________________________________________________
>MSN Photos is the easiest way to share and print your photos: 
>http://photos.msn.com/support/worldwide.aspx
>

=========================================================  
- Government: The other religion.
- The media's credibility should always be questioned.
- Lambs who lie down with lions are lunch.

-- Scott Gravenhorst | LegoManiac / Lego Trains / RIS 1.5
-- Linux Rex         | RedWebMail by RedStarWare
-- FatMan: home1.GTE.NET/res0658s/FatMan/index.html
-- NonFatMan: home1.GTE.NET/res0658s/electronics/index.html