The discriminator output is made on pin 11 of the
discriminator-IC, a 10489. One lead of a 'safety resistor' of 10 k
(the exact value is not critical, I use values between 5,6 and 15
k) is bent to follow the IC's pin exactly. Then, the resistor is
connected to pin 11 of the IC using a fine tip soldering iron and a
minimum amount of solder. The resistor is fixed to the IC with a
drop of glue from a glue gun. This prevents damage to the IC pin
when inadvertedly mechanical stress is applied to the
resistor.
To the other side of the resistor, I connected a small
piece of insulated wire, which leads to the 3.5 mm chassis
terminal. It's not very long, and runs between two PCB's, so it's
not necessary to use shielded cable.
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