Bosch DMF10 Zoom Detector - What Do You Think?

I've been reading this post on DIYnot with interest.

Someone had an issue with their Bosch DMF10 Detector and was so frustrated he wrote in to the forum to tell that it almost always detected mains voltage, even when there was none anywhere near the detector.

He got various replies from people who had and hadn't used the tool to say that they were satisfied or otherwise.  The original contributor eventually came back and said he'd worked out what the problem was.

This tool is one of the top sellers at Toolstop and although we haven't had too many returns we have had a few, mainly due to users not using the tool correctly as in the example above.

I'd like to set the record straight on the Toolstop blog so I want users of the tool to let me know what they think.  Is the tool good, bad or indifferent. Have there been times the tool didn't work in the way it should?  Any tips on the correct usage of the tool?

Please let us have your opinion in the comments box so we can tell the community about the Bosch DMF10 Zoom.

UPDATE 29th January 2010

Thanks for all the great feedback.  We are arranging for an official response from Bosch in Germany.

Meantime, having spoken to various contributors and to Bosch I have listed a few "best practices" below.  It is clear that you're not all happy with the tool but during my various conversations I am convinced this IS a great tool if used correctly.  I've attached the user manual and I've quoted a few important points from it below.

• The tool may have been in your van before you use it - let it acclimatise itself to the ambient conditions before use
• Wipe it down - it may be damp
• Check the specs and ensure you are within them, particularly the depths of measurement

As Vic Faulkner said, "resolved by first moving a hand over the area of the wall before placing the detector on the wall" - this is an important factor, you need to be fully earthed so there is no static in you or the machine.  Small things like rings or watches can interfere with the measurements.  This is all covered in the user manual.  It is very important to read the full manual (only 6 pages) to ensure tthe correct use of the DMF10.

Some details from the user manual:

When the measuring indicator f continuously shows an amplitude even

though there is no metal object in the vicinity of the measuring tool, the

measuring tool can be calibrated manually. For this, remove all objects

in the vicinity of the measuring tool (including wrist watches or rings of

metal) and hold the measuring tool up in the air. With the measuring tool

switched off, press both the “on/off” button 7 and the wood-detection

button 5 until the illuminated ring 1 lights up red and green at the same

time. Then release both buttons. When the calibration process was successful,

the measuring tool will start over after a few seconds and is then

ready for operation.

Wipe away debris or contamination with a dry, soft cloth. Do not use

cleaning agents or solvents.

In order not to affect the measuring function, decals/stickers or name

plates, especially metal ones, may not be attached in the sensor area 9

on the front or back side of the measuring tool.

Do not remove the felt pads 8 on the back side of the measuring tool.

Replace the felt pads when they are damaged or used. For this, completely

remove the felt pads and glue the new felt pads onto the same

spots.

Store and transport the measuring tool only in the supplied protective

case.