Projects in the April 2001 issue of EPE Magazine

Intruder Alarm Control Panel - our 5-zone professional-standard controller forms the heart of a security system compliant with British Standard BS4737. Has exit/ entry delays, auto reset, bell shut off, walk test and many other options. Separate bell module also described.

In the June 2001 issue (P.431) we published corrections as follows. Page 357 Fig 5: unfortunately the main p.c.b. component layout shows some of the diodes incorrectly annotated. They should be as follows: D5 becomes D22; D6 becomes D11; D7 becomes D12; D8 becomes D6; D9 is ok; D10 becomes D8; D11 becomes D10 and D12 becomes D5; D22 becomes D7. The circuit and components list are correct. The author also adds that the battery for the extension bellunit mayb e any voltage between 7.2V and 12V, rated approx 250mAh, Ni-cad or sealed lead-acid.

Snug Bug Controller - A 4-channel personal "central heating" system for your tropical pets. Up to four thermostatically controlled dry heat pads can be used, for snakes, toads, lizards and other reptiles.
Wave Sound Effect - Bring the relaxing sound of the sea into your home! Use our electronically-created "sea sound" to mask annoying background noises. Uses a near-"pink" noise circuit to produce gentle, soothing effects similar to the sound of gentle rainfall. Battery powered, headphone operation.

Sound Trigger - another "Top Tenner" project that can be built for about ten pounds ($7). This battery-powered project lights a small bulb when sound is detected by the built-in microphone. Instructive, economical and safe, this project is ideal for younger constructors or beginners.

The SchmittTtrigger: Part 6 of our In-Depth Designer's Guide related to Schmitt applications

Also in this issue - FREE SUPPLEMENT - An End to all Disease. Can disease be cured electronically? Read our story of electronics, blackmail, intimidation, theft, bribery and even murder! Also in this issue - New Technology Update - 3D LCDs become reality. Ingenuity Unlimited (readers' own circuits), Practically Speaking (construction tips), Circuit Surgery (phase-locked loops explained).