Magnetic
Field Monitor Build our sophisticated flux gate sensor to monitor static and alternating magnetic fields around the home, e.g. from nearby electricity pylons. Meter/ headphone output.
Hosepipe
ControllerUse water in your garden more efficiently and avoid wasting money and water, with our low voltage timer unit. Lead acid battery powered, solenoid valve control of water supply, 15/30/60 minute timer. Photocell option allows daily light-sensitive operation. Low battery indicator.
Dummy
PIR DetectorA very inexpensive and easy to construct device intended to deter opportunistic thieves. Low voltage transistor l.e.d. flasher running from just 2 "AA" cells. Ideal beginner's project.
In
Circuit OhmmeterThe last of our "Top Tenner" circuits which can be built for under £10 ($14 or so), this circuit enables you to measure in-circuit resistance without having to remove components. How's it done? Read our Top Tenner article to see!
Special Feature: PIC16F87x extended memory - how to use the additional memory banks of PIC 16F87x devices. Now you can "address" those memory problems with our feature article! Includes Register maps of PIC 16F877/ 876 and PIC16F874/ 873. Controlling Jodrell Bank An insight into how electronics plays a vital role in our investigations of the Universe. Practical details of some of the technology behind some of the world's most sophisticated radio telescopes, at Jodrell Bank in the UK. Also in this issue: New Technology Update looks at silicon-germanium semiconductor architecture; Net Work describes the Open Directory project (ODP); Practically Speaking shows you how to handle static-sensitive devices. Circuit Surgery offers more advice on impedance matching.