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Jeff Wisnia wrote:
> Homer J Simpson wrote:
>
>> "Jeff Wisnia" <jwisnia@xxxxxxxxxxxxxx> wrote in message
>> news:zLydnZVzrJEpLYfYnZ2dnUVZ_tWdnZ2d@xxxxxxxxxxxxxxxxx
>>
>>
>>> I believe the ammmeter is what I used to know as a "moving iron"
>>> type, and IIRC the restoring force was supplied by some kind of
>>> permanant magnet field, not by a mechanical spring. Am I right about
>>> that?
>>
>>
>> Nope. Still a spring.
>>
>> http://www.tpub.com/content/doe/h1011v4/css/h1011v4_76.htm
>>
>> Moving iron vane - The moving iron vane meter operates on
>> the principle of magnetic repulsion between like poles. The
>> measured current flows through a field coil which induces a like
>> magnetic field into a fixed and moving vane causing the moving
>> vane to deflect a pointer in proportion to the current or
>> voltage applied to the coil.
>>
>>
>>
> I hear what you say about a spring, and it makes sense that there may be
> one there. But it's interesting that the reference link you gave
> mentioned "springs" when describing the first two meter types, but not
> the moving iron one. Wonder why? Probably just an oversight.
>
> Jeff (Who is NOT going to tear that old meter on the Eico 1050 apart to
> find out.)
Hit the 'Back' link at the top of the page above and you'll see the
spring.
--
Graham W www.gcw.org.uk/">http://www.gcw.org.uk/ PGM-FI page updated, Graphics Tutorial
WIMBORNE www.wessex-astro.org.uk/">http://www.wessex-astro.org.uk/ Wessex Astro Society's Website
Dorset UK Info, Meeting Dates, Sites & Maps
Change 'news' to 'sewn' in my Reply address to avoid my spam filter.
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