Epson HX-20 repair details

From: M.Clemence <M.Clemence_at_exeter.ac.uk>
Date: Mon Oct 14 13:10:52 2002

Hi there,

I have a two Epson HX20's (which we use in our reasearch lab - yes still
- to control some
equipment) one of which has sufferred a failure of the power supply on
the main CPU
board (details below) and I need to get hold of a schematic if one
exists. I beleive that Epson produced
a repair guide - does any one know where I might be able to source this
information.

I have had a plough through the archives to this list and there are some
very helpful people out there
and maybe if anyone has some experience with this machine and can give
me pointers - the following
might help ...

The batteries and external adaptor are good (new) charging correctly and
delivering 4.8 V.
However, the power switch has no effect (no LCD, no beeping)

The main power rails seem to be off - there is 4.8 v at one test point
0 at another an 2.8v scattered
around the board. There seems to be no 17 V which I beleive is needed
for the LCD.

The previous owner reported a burning smell so component failure is
suspected, but no obvious signs
on the transistors.

A previous writor in the archive (Tony Duell) suggests that a volatge
should be present on the collector of Q8,
this is absent.

Thanks in advance

Yours

Matthew Clemence
Received on Mon Oct 14 2002 - 13:10:52 BST