[Test-Equipment] FS: Heath IM4180 FM deviation meter

[Richard Knoppow]

----- Original Message ----- 
From: <kc7hkp at comcast.net>
To: "Discussion of Electronic Test Equipment" 
<test-equipment at mailman.qth.net>
Sent: Monday, April 21, 2008 1:25 PM
Subject: Re: [Test-Equipment] FS: Heath IM4180 FM deviation 
meter


> Hi Dick
> What is FM Deviation ?
> I have not heard this word before in ham radio .
> Sorry to bother you
> George
>
    In case this is a serious question...
    Deviation is the measure of the amount of frequency 
modulation in an FM signal. It is superficially the amount 
the carrier is changed in frequency when modulated. There 
are several ways to measure the amount of FM but its 
possible to make a fairly simple device to indicate it on a 
meter although other methods are more accurate.
    FM transmission became popular for the ham bands after 
WW-2. It has pretty much disappeared on the HF bands but is 
quite widely used on 6 meters and above.
    The other reaction to the question is because FM should 
be elementary knowledge. OTOH, no one should be afraid to 
ask a question for fear of being humiliated.
    May I suggest that a Google search is a good place to 
start for definitions.

---
Richard Knoppow
Los Angeles, CA, USA
dickburk at ix.netcom.com