Sinclair's long-standing enthusiasm
for hi-tech names revealed itself in the X-10,
an audio amplifier designed by Gordon Edge which used
a new technique called pulse width modulation. It aroused
a lot of interest, as nothing of similar size, price
or performance had been seen before.
Unfortunately, Sinclair's claims were a little too
extravagant and the amplifier ran into the first advertising
standards problem of Sinclair’s career. Wireless
World reportedly refused to take Sinclair’s subsequent
advertising for the X-10 because of complaints over
the performance claimed for the amp. Its stated output
was 10 watts R.M.S., but in reality it was capable of
only a quarter of that, and was temperamental to boot.
The debut of the X-10 was also fraught with problems.
The original circuit design had been delivered to Sinclair
Radionics accompanied by a working prototype; Jim Westwood
took the prototype and engineered it into a marketable
form which was sent to the firm in Hampshire which manufactured
Sinclair's circuit boards. They promised that the first
batch of boards would be delivered within a few days,
and the first advertisement for the X-10 was planned
to coincide with promised deliveries.
The boards arrived exactly on time. They looked all
right at first, and Westwood set about building the
first real X-10 amplifier. But disaster struck - the
board was a mirror image of what should have been and
the whole batch was useless. By the time the correct
boards had been made and an amplifier built, the X-10
had been appearing in advertisements for some time,
with many customers wondering when their amplifiers
would arrive. This was the first but by no means the
last time that technical problems were to cause major
delays to deliveries of a Sinclair product.