This meduci high quality AM STEREO outboard Decoder Converter PC Board
is assembled and tested; based upon the popular solid state Motorola
MC13028AD third-generation decoder IC chip. Please consult the Motorola
‘MC13028A.pdf’ data sheet for further details concerning all features and
operation of this decoder. There are six connections that need to be made to
the host AM tuner or AM receiver from this PC board. Composite-level
intermediate frequency (I.F) signals, taken from the mono receiver, are
detected and decoded into line-level left and right audio outputs back into the
host receiver. There is also a convenient AM stereo indication to drive LED.
In the absence of a good, strong, and solid AM stereo signal, an un-degraded
mono output will be provided from both audio channels.
This add-on decoder functions with the Motorola C-QuAM stereo system,
and provides full separation stereo reception from local AM stations
transmitting the C-QuAM encoded format, where available.
It is best to install this decoder into digitally-tuned PLL quartz-synthesized
host AM tuner or receiver for best results. Manually-tuned radios usually do
not have the low-phase noise stable local oscillators that this MC13028AD
decoder board requires to provide reliable C-QuAM stereo reception.
There are not any adjustments or modifications necessary to the decoder
board circuitry. New 3.6MHz ceramic resonator offers wider stereo lock-in
range to the incoming I.F input. New CFU450B ceramic filter on-board.
Attractive green printed circuit board adds to the appearance.
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