Thread: 52 dB any good?
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Old April 27th 06, 06:45 PM posted to uk.rec.audio
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Default 52 dB any good?


"Serge Auckland" wrote in message
...

"Keith G" wrote in message
...

My new/old Technics tuner advises me my FM signal strength is 52 dB - is
that good, bad or just plain ugly, given the palaver with the aerial
installation a while back?

TIA

(Also posted to the vinyl group in error!)

Keith,

Without knowing what the 0dB reference is, it's difficult to know *what*
they mean.

If the signal strength is -52dBm into 75 ohms, then that's a voltage level
of 687uV which is a bit low. Knowing where you're located and how far from
Peterborough, I would have expected some 2mV at the tuner, but maybe you
have some high ground between you and the TX. If the tuner doesn't hiss on
Radio 3 in the evenings when the processing is turned off, then you should
be OK even on the signal you have. Most tuners achieve 50dB S/N ratio with
under 100uV, but don't reach their maximum S/N ratio until nearer 1mV.

S.




Keith

Didn't the mast at Peterborough fall down a while back, after the
transmitter building at the bottom caught fire ? Left them with temporary
transmitters, and a rather shorter than normal mast ? Might be wrong -
probably somewhere completely different ... I wouldn't expect a Technics
tuner to declare an accurate value for received signal level anyway - after
all, it's not designed as a signal strength meter. I should think that it's
one of those flim-flam feel good indications based loosely on how much AGC
is being produced. Keeps the technophiles happy ...

Arfa