The Realistic PRO-26 is quite a challenging scanner to equip with a discriminator output. The receiver IC, a TK10930, is a VSOP (Very Small Outline Package) IC. Its pins are spaced 0,5 mm (0.02''). A 'normal' SMD has a spacing of 2.5 times this size.

PRO-26

Pin 12 contains the unfiltered audio

Close-up of the discriminator output

Pin 12 contains the demodulated baseband signal audio. Luckily, this pin is situated at the end of the IC, and not between two pins. One lead of a 10 k resistor is bent to follow the IC's pin exactly.

Then, the resistor is connected a little to the outside of pin 12 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.

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