Vintage Ekco RCX 'Ekcosprite' - Volume won't turn down to zero

I was working on restoring an old Ekcosprite recently and came across a puzzling problem where the tubes all tested fine, as did all the components (many were replaced and new)... but I could not shut the voume fully off.  It took some experimenting and head-scratching - and finally a little Googling to figure it out.

Ekcosprite RCX

Murphy (F&P) Service Information for various models

Fisher and PaykelRecently I aquired a large folder full of service information for the NZ designed and built 'Murphy' range of radios, TV's and grams from the 60's and 70's.  This brand was produced by Fisher and Paykel - who's main claim to fame these days is whiteware.

Philco 'Alabama' - NZ Model

Philco 401 'Alabama' Front

Philco 401 'Alabama'

Philco 401 'Alabama' Rear

Crystal Sets Revisited

 Well, my original crystal set post had some experimentation on it, and I have done a little more recently due to wanting my daughters Cub Group to build one as an experiment.  The biggest hurdle was getting the cost down to a resonable figure - otherwise the project was dead in the water.

Spider Coil Calculator for Radio Applications - Python Code

In my crystal set post I use spider coils, because they are easy to make (my 8yo daughter wound one all by herself), and because they have better Q than a TPR coil (Toilet Paper Roll - common type used in basic crystal sets).

Crystal Sets

s a child, my father got me into building my first crystal set.  I don't fully recall the details, but I seem to recall it was a kitset and I was in Nelson when I built it - If I remember I'll ask him.  What I do remember is building a few of them, including one that fitted inside a tic-tac container and another that had no tuning cap, just an icecream stick with a screw through the end that scratched through to vary the coil windings in use.