Regency M100
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The Regency Touch M100 is is a vintage scanner, and
as it is a pre-SMD scanner, it's not a big deal to add a discriminator
output.
The discriminator IC is an unknown 18 pin DIL IC. It is stamped
'Regency 600-565'. |
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Regency Touch M100
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Using an oscilloscope, pin 10 of this IC appears to
contain the unfiltered baseband signal. A solder point next to pin 10
appears to be connected directly to the IC. A 10 k resistor is soldered
to TP5. The resistor can be mounted vertically.
Because the discriminator output contains a slight IF component at 455
kHz, the other lead of the resistor is connected to a grounded 2.2 n
capacitor. This creates a simple RC lowpass filter with a cutoff
frequency of about 7 kHz. The IF signal is suppressed effectively. The
ground lead of the capacitor can be connected to the shield of the IF
coil nearby. |
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Pin 10 of the IC contains the unfiltered audio
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Simple RC filter with shielded wire
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| A piece of shielded wire connects the discriminator
output to a 3.5 mm chassis terminal in the back of the scanner. The
core of the wire is connected to the junction of the resistor and
capacitor. The braid is connected to the metal shield of the IF
coil. |
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