From: Hornstein <yz0i398001@sneakemail.com>
Subject: Sound of the TCD-D8 light measured
Date: Thu, 28 Mar 96 10:09 +0100

Hi DAT-Heads,

a few days ago there were some opinions in the digest on the
sound produced from the D8 light. I tried to measure it:

        A reference tone of -60 dB was recorded.

        After this, pure silence was recorded, in 10 sec intervals
        the light was switched on and off.

        For playback and measurement, the output signal was
        amplified.

        At playback, a tone was just clearly audible during "light
        on intervals", same/similar frequency as the sound that
        can be heard while watching the light being "on".

        I could not measure the level of this tone, because it was
        not distinguishable from the output noise, which was about
        at -84 dB (my amplifier might have added some noise).

        No "click"-sounds were heard when the light was switched
        on or off.

This means:
"Light on" causes a tone to be recorded on tape. But it is so soft
that it will not disturb performance in usual applications.

Greetings from Freiburg, Germany
Ulrich Hornstein