Tuner deviation meter ?

Hi could someone explain the purpose of the deviation meter on my Fisher fm-2310 tuner.
Thanks for any info,
Analog FM tuners had a meter to help you get tuned accurately to the station's carrier frequency (Which is modulated to reflect the audio signal). Proper tuning minimizes distortion and noise. The meter should be adjusted for null: ie: centered.

Digital tuners don't have meters except for signal strength which is used for pointing a directional antenna. Tuning of a digital tuner is based on its crystal oscillator, which is more accurate than anyone could do twiddling a knob.
Eldartford, are you sure you have the right meter for your description? My deviation meter on my Kenwood KT-917 moves with the signal level. (i.e it bounces around as the signal level changes, like the signal meters on a cassette deck.)

The more expensive vintage analog tuners/receivers actually had two types of signal meters for FM reception:

1. A signal strength meter, which is the type that Brian was referring to. This meter moved in conjunction with signal strength.

2. A signal tuning meter, which is the type that Eldartford was referring to. This meter is a centering type meter. Really old vintage equipment (post WWII Grundig receivers) used a tuning "eye" for these purposes.

The more basic receivers usually went with one meter ... the signal tuning type.

AM reception usually piggybacked off the signal strength meter. The idea was that when you were receiving the strongest AM signal, it was tuned about as well as you could get.

There are meter-less vintage receivers/tuners out there. You get to use your ears to best tune stations on those receivers.

Regards, Rich
Hi, my Vintage Fisher has three meters one centers on a station being in tune, one sweeps to the right to show signal strength, and one marked Deviation which moves along with the program meterial but not like an vu meter. I have an idea that there is a difernent information given by this meter, but not sure what.
Thanks again for any help - Guycom

Here's a thread from the Audio Asylum/Vintage Asylum that mentions the deviation meter ...

The KT8300 is the only tuner I know, (well, besides the KT-917/600T) that has the cool deviation meter. This is great for understanding the quality of broadcast stations. The ones where the meter sits at 100% are basically compressing the life out of the music. On other stations, I see the meter bounce between 0 and 90, which is what you want for good dynamic range.

Regards, Rich
Rich wins the prize this time. Deviation meter does indeed show you how far the station is deviating from center. Less deviation generally = lower distortion but lower overall audio level. Hence, we compress and limit the signal.

Eldartford: Nice try, but center tuned is almost never the best spot. I've seen one tuner--ONE!--where center tuner was actually the best spot. The rest were all out of alignment.