The DFT has two digital inputs: one Toslink (optical fiber) and one RCA
jack (coax). A toggle switch controls a logic element that selects
between the two. It has two outputs that are always active, one Toslink
and one RCA jack. This lets you add the format that you're missing and
retain the one you have. Or if you already have both output types, it
lets you add a second of one type. With two DFTs you can add one more
of each. With the DFT you can also convert signals between the two
formats.
By adding a short (18-inch/45 cm) cable adapter to interface the Sony
7-pin connector to the DFT's RCA coaxial input jack, the DFT provides
both coaxial and Toslink outputs from the Sony portables. With the
7-pin input adapter cable in place the DFT selects between 7-pin and
Toslink inputs. If you don't need the 7-pin input, just unplug the
adapter cable and you get the RCA jack back.
We also have a modification to the DFT that provides a 7-pin output
connector/adapter cable in addition to the RCA and Toslink outputs.
Toslink is usually limited to cable lengths of 10 to 15 meters. The DFT
acts as a repeater to regenerate the digital audio signal so by using
the DFT you can run Toslink for 20 meters or more.
The DFT is roughly the size of a pack of cigarettes, housed in a rugged
cast aluminum black case, and powered by an optional six-to-twelve volt
wall-mounted power supply. The power supply plugs into a 5.5/2.1mm DC
power jack (center pin is positive) on the DFT case. The DFT will
operate on power supplies all the way down to 5.5 Volts so it can be
powered by the same external battery that you use to power your Sony
portable DAT and MD machines. It draws 100 milliamperes of current and
so can run on a fresh 9 Volt alkaline battery for more than 4 hours --
an optional 9 Volt power cable is available. A red light emitting diode
on the DFT case lights up when power is supplied. Both 110 Volt and 220
Volt power supplies are available.
To prevent ground loops and the interference they can cause, the DFT's
RCA input and output jacks are fully transformer isolated. Since the
DFT's coaxial I/Os are fully transformer isolated, the 7-pin input is
too. There's no worry about ground loops.
The DFT does not manipulate SCMS in any way.
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