components

Mention must be made here regarding the cleaning of the keyboard.

The unit above it particularly dirty - with some corrosion.

The original instructions suggested 'occasional use of a light abrasive metal cleaner' to maintain proper
performance. The obvious implication is that the board could wear through with over cleaning with abrasive
cleaning materials. It is, after all, only printed circuit material

This example has been removed
from the case prior to a good
cleaning of the keyboard.

The white lead is to the stylus; the
red and black leads at left connect to
the battery.

This is a standard white model with
plain keyboard.

In this case, chrome cleaner paste and a lot of
elbow grease is called for.

This particular board came up very well indeed
after its' cleaning, and despite reservations about
being too harsh on the board, this may well be your
only option to get it back to something like a
respectable finish.

After cleaning, there were no signs of wear at all,
and I would suggest this method without too much
worry. one area to be careful of however, are the
narrow 'tram lines' surrounding the keyboard; break
through one of these and your into a lot of
unnecessary, time consuming work!.

The preceding pictures are basically to show you what's inside your Stylophone, and unless your own model is
showing this sort of dirt or corrosion, it would be best to leave it as it is.

Some models have boards that are easier to remove than others, and some flexing of the board may occur.

This could lead to a cracked board, or de-soldered joints...nightmare!.

So what are the differences in the circuits?

Well, it's more the components than anything else. As newer, and smaller resistors, diodes, transistors etc. became
available, they were incorporated into the board. This makes for fascinating investigation when examining several
units, as you can see the progress through the years as the more compact bits and pieces, and more efficient no
doubt, (resulting in longer battery life), are used in manufacture.

Rule of thumb: Big bits - Old Stylo.

Small bits - New(ish) Stylo.

This is not a hard and fast rule, as components could have been used from a number of different
sources, and cannot be relied on, but the photos below show some of the obvious differences: