Electronics Projects

  • Budget Multimeters

    Budget Multimeters

    Not everyone can afford or justify expensive professional equipment in their hobby workshops, but while cheap multimeters are plentiful, are they any good? What are the potential problems with cheap multimeters? Which ones should you consider?

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  • Time Electronics 1030 Micro Cal

    Time Electronics 1030 Micro Cal

    This unit is a precision hand-held voltage and current source that is incredibly neat and compact, and is still hand-made in the UK after more than 25 years of production. I present a review, tear-down, technical investigation, and restoration. Enjoy!

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  • AD584 Voltage References

    AD584 Voltage References

    Curious about those cheap voltage references that are all over eBay, I ordered up a batch for investigation. Measurements and full schematics are included as part of the reviews.

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  • Statistical DVM Reference

    Statistical DVM Reference

    A precision voltage source is a useful addition to an electronics workshop, and there are many ways to make one. This simple design uses a "statistical reference" and offers 10 output voltages with significantly better than 0.1% accuracy. Output protection and a low-battery indicator is included.

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  • Radiometer SMG40


    This is a pretty obscure bit of vintage test gear that is used for setting up stereo radio receivers. This article includes a brief look at the basics of FM stereo broadcasting, a good look inside the unit, and details of the repair.

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  • Mains Distribution Unit

        Distribution Unit

    A simple project that started out as an investigation into cheap mains voltage/current modules. It snowballed into a significant "re-engineering" exercise, but the result has been incorporated into a mains distribution panel that is for "equipment under test", complete with monitoring outputs.

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  • Isolating Transformer

        Isolating Transformer

    An isolation transformer is essential for safely carrying out certain types of repair and development work, and was something that was missing from the workshop for too long. After a studio refurbishment at work, I rescued the parts needed to make a decent dual unit.

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  • Active Speaker

    Active Speaker

    A simple powered loudspeaker based on a TDA2030. This was intended to be used as a bench speaker, but as it actually sounds quite nice it has spent most of its life as my bedside radio! This project has recently been updated, including a different (and available) drive unit...

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  • Dual Power Supply

       Power Supply

    This is a dual power supply with digital metering. It was originally intended with use with op-amp circuitry development, so has a split output with options for accurately tracking either section. Naturally, it has precise current limiting and digital metering.

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  • Telequipment DM63


    Many years I was given this old Telequipment scope; unfortunately it had a trigger fault caused by an obsolete custom-made IC. As it was impossible to source, I built a circuit which replaces the functionality of this IC. Also, many other faults have been encountered, all of which are detailed.

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  • Battery Monitor


    This is part of the garden shed project; a simple circuit that is both a light switch and a lead-acid battery monitor which protects the battery from deep discharge.

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