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Beware fake wire!
I bought some test leads with banana plugs and alligator clips for £0.99 on Ebay from Hong Kong. They were described as "Alligator Probe Test Leads Clip Pin to Banana Plug Cable for Digital Multimeter GF". I don't know what the GF means. Very cheap and what...

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Beware of cheap Kelvin clip LCR meter test leads
When I first got my Elektor LCR meter I didn't have any four wire test leads for it so I made up a pair from the ends of an old VGA monitor cable and some miniature crocodile clips. These worked well enough for measuring normal components but they are not t...

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Elektor 500ppm LCR meter case tips
I recently bought a 500ppm LCR meter from Elektor because I didn't have anything for measuring inductors or the ESR (equivalent series resistance) of capacitors, both of which are important for modern electronics, particularly switch mode regulators that ha...

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Cool maps
The aim of making the instrument described in the last post was to be able to quantify the cooling effectiveness of various fan and duct combinations by sampling the airflow at a grid of positions around the nozzle. I attached the denuded bulb to the termin...

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Added CraftWare to the list of slicers that can't slice my fan duct. Any others I should try?

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Quantifying cooling
A few months ago Neil Darlow mentioned that he had replaced his Mendel90 fan with a quiet version and it seemed to give better cooling results. This made me curious because quieter fans of the same dimensions generally spin slower and produce less airflow. ...

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A bridge too far
This version of the Mendel90 fan duct that accommodates the E3D V6 hot end happens to be a shape that is surprisingly difficult for slicers. It is because of the shallow sloping slanted bridge. Skeinforge I slice everything I print with Skeinforge, so the n...

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Telequipment D32 trace rotation fix
Another ancient piece of equipment I have is this Telequipment D32 mains / battery operated portable oscilloscope. Telequipment is an old brand name used by Tektronix in Europe. I think it was made in about 1972 for servicing TVs. I bought it in a broken st...

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Tektronix 8560 still going strong
And now for something completely different... I
have been tidying my lab post kit production to make room for future
experiments. In the process I have been skipping loads of junk. I do
have trouble throwing things away that work just as well as when the...

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Ultra Low Dropout Regulator for flicker free LEDs
Cheap 12V LED lighting strips are very sensitive to small voltage changes. This is because they just have multiples of three white LEDs in series plus a small resistor to set the current. The voltage across the LEDs is more or less constant at 3 × 3.2V, so ...
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