FEBRUARY 2006 £3.80 - Index of

the popularity of the Simpson
260 multimeter (on Ebay, at
least) must be that it’s still
being used in aircraft maintenance.
In fact, a number of
Boeing aircraft maintenance
documents mention the use of
the Simpson Model 260!
Christian Wendt (Germany)
Retronics on multimeters
(2)
We thank Mr. Reznor of
Solihull for sending us a copy
of the Philips PM241 multimeter
service documentation
and user manual, as well as
for confirming that the instrument
was first sold in 1971.
The user manual confirmed
our assumptions about the
use of the strange ‘I/0.4’
pushbutton on the range
switch of the PM241 and its
successor model the
PM2411.
Improved DECT battery
charger
Dear Editor — I’d like to
respond to your Summer
Circuits item entitled
‘Improved DECT Battery
Charger’. Basically, your
story is correct and it is desirable
to reduce the charge
current of NiCd batteries on
permanent charging to levels
even smaller than 0.1 C. So
I decided to have a go at my
own DECT set.
The charger with the set
looks a bit different and consist
of a current source built
from a diode and a transistor,
the latter supplying about
30 mA. The batteries in the
phone are 280 mAh types. I
reduced the current to about
18 mA (approx. 0.065 C)
by increasing the value of the
resistor in the current source.
The result: flat batteries after
about two weeks. It then
occurred to me that the
phone itself also draws current
when placed in the
charger pod. So, in my case,
the manufacturer did manage
to design a proper charger.
Nico de Vries (Netherlands)
A valid point Nico that should be
taken into account when dimensioning
the charge current.
Thanks for letting us know.
Elektor Year Volume
CD-ROM problems
Dear Jan — I am unfortunately
unable to install the Elektor
annual CD-ROM.
After running Setup, I get the
error report:
16-bit Windows subsystem
C:\winnt\system32\autoexec.nt
System file unsuitable
for ms dos and Microsoft
applications.
Next, when I run
EASETUP.EXE, something is
being installed and I am
informed that the installation
is successful. However, when
starting the Archive program
I once again get the above
error report telling me the
system file is unsuitable. I am
using Windows 2000
Professional. Can you help,
please?
K. Johnson (UK)
We not only know the error
report, we also have the solution
to the problem.
From the directory
‘c:\winnt\repair’ copy the file
‘autoexec.nt’ and paste it into the
‘winnt\system32’ directory (i.e.,
Xmas Special edition
(1)
Dear Editor — I have just
received the December
2005 edition of Elektor
Electronics magazine
and the articles make,
as usual, very interesting
reading.
However, I am disappointed.
Your previous
December issues carried the
Xmas Special 30 circuits
and design ideas for the
Xmas holidays. These are
missing this year and I feel
you have let us down. I
hope to see them again in
next year’s Xmas edition.
Ken Barry (UK)
Xmas Special edition
(2)
Dear Jan — what happened
to the circuit supplement in
the December issue?
I always looked forward to
these idea-provoking small
projects. I was disappointed
to find the supplement missing
from the December issue
after 15 years with no
explanation or statement
that the feature had been
suspended.
As a result of this, the magazine
seemed a bit ‘thin’ for
articles. I do not expect
every issue to be full of articles
or projects that are of
interest to me, if that were
so, I would not have been a
subscriber since 1978.
Generally Elektor does very
well to provide a varied mix
of interesting and useful articles
and projects, written by
some excellent contributors
and staff writers. So this letter
is not intended as a criticism
of the magazine, more
as to observe that a feature
has disappeared without a
word of explanation after
being enjoyed for so long.
Please bring back our supplement
!!
Pat Redway (UK)
Thanks Ken, Pat and other readers
who wrote us on the same subject.
There are no longer 30+
small circuits
in the December issue
because all 100+ we produce in a
year have been included in the
‘Summer Circuits’ issue. At 144
pages the 2005 Summer Circuits
edition was the thickest issue of
Elektor Electronics ever printed.
So, we have not let our readers
down and in fact have again
published more articles in a year
volume than any of our competitors
on newsstand distribution in
the UK.
Starting in 1988 and ending in
2004 (and only in the Englishlanguage
version of Elektor), 60-
70 articles from our annual stock
went into the July/August (‘Summer
Circuits’) issue, and the
remaining 30-35, into the
December issue. Due to centralized
production and simultaneous
printing of all four-language
editions of Elektor, in 2005 we
changed this to 100+ articles in
the July/August issue, thereby
restoring an Elektor tradition in
existence between 1975 (the
year of our first issue) and 1987.
The change was duly
announced in the June 2005
magazine as well as in several
news items on our website;,
sorry if you missed these. I am
pleased to say that we had an
encouraging amount of positive
feedback in response to the
return of the 100+ items version
of the ‘Summer Circuits’ issue.
The change was rewarded with
newsstand sales figures nearly
10% up as compared with the
previous year.
Besides articles in good Christmas
spirit, the December 2005
issue contains four major construction
articles and three
design tips which, I hope, have
kept many readers busy over
the Christmas holidays.
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