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Notes & Errata Sustain Unit for Electric Guitars, March 1998: the BFR84 dual gate Mosfet (Q1) is no longer available. The solution is to substitute a 2N5484 N-channel FET, as shown on the accompanying overlay diagram. An extra 22kΩ resistor is required to alter the level control voltage range from VR3 and this can be connected between pins 2 & 4 of IC2a, on the back of the PC board. Also the 0.1µF capacitor between pins 8 & 9 of IC1c should be changed to .001µF. Have I missed something? (Doug – via email). • The 5.25V RMS that you are obtaining at the 0dB output of the pink noise source must be a measurement error. This is be­cause the circuit is powered from a 9V battery and even if IC1b is being over-driven, it could only deliver about 3V RMS. Perhaps you are measuring the DC voltage at the output of IC1b which should be sitting at around half supply. Check the 10µF capacitor at this output to see if it is short circuited. Improving the ignition on a Honda I have a 1994 Honda Integra VTIr and was wondering if I could use the Multi-Spark Capacitor Discharge Ignition kit (September 1997) on it. I have seen similar products on the market such as the Crane Hi6 ignition amplifier so I figure that this kit would do the same thing but at a fraction of the cost. I have provided a portion of the installation of the Crane Hi6 for you to read, as it looks similar to your kit. (Thanh – via email). • Since your car already has a very comprehensive engine management system which includes solid state ignition, we cannot see the point of fitting the Multi-Spark CDI or any commercial aftermarket system. The only possible justification for fitting a high­er output ignition system would be if the engine has been substantially mod­ified to either increase its rev limit or its compression ratio. In our opinion, since you already have a highly developed engine, you would be wise to leave it alone. Identifying an unknown PC board I have a kit with a PC board number SC09111931 which has a missing output transistor (the big one with the heatsink). I was wondering if you can tell me what the transistor is or where to get information on this kit. (Michael – via email). • If you search in the projects index on our website you can identify any project from the board number. This board was a simple low voltage speed controller featured in the January 1994 issue. The transistor is a BD679 and can be obtained from Jaycar, DSE, etc. WARNING! SILICON CHIP magazine regularly describes projects which employ a mains power supply or produce high voltage. All such projects should be considered dangerous or even lethal if not used safely. Readers are warned that high voltage wiring should be carried out according to the instructions in the articles. When working on these projects use extreme care to ensure that you do not accidentally come into contact with mains AC voltages or high voltage DC. If you are not confident about working with projects employing mains voltages or other high voltages, you are advised not to attempt work on them. Silicon Chip Publications Pty Ltd disclaims any liability for damages should anyone be killed or injured while working on a project or circuit described in any issue of SILICON CHIP magazine. Devices or circuits described in SILICON CHIP may be covered by patents. SILICON CHIP disclaims any liability for the infringement of such patents by the manufacturing or selling of any such equipment. SILICON CHIP also disclaims any liability for projects which are used in such a way as to infringe relevant government regulations and by-laws. Advertisers are warned that they are responsible for the content of all advertisements and that they must conform to the Trade Practices Act 1974 or as subsequently amended and to any governmental regulations which are applicable. JULY 1999  93