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Next Issue The October 2016 issue is due on sale in newsagents by Thursday 29th September. Expect postal delivery of subscription copies in Australia between 29th September and October 14th. Ask SILICON CHIP . . . continued from page 111 causing insulation breakdown. Having a fully floating supply that is not Earthconnected and that does not have the possibility of becoming live via the mains is the safest option. The high-tension voltage is considerably dangerous on its own without added safety compromises. Can’t get Multi-Spark CDI to work I’ve bought your December 2014 and January 2015 magazines, hard to get parts, etc and made the High Energy Multi-Spark CDI Ignition, designed by John Clarke. I am using a reluctor pickup system and I installed the unit and tried to set it up as per the January 2015 article (as described under “Testing”) . With all wires connected (except the tacho), I was able to set the output to 300V DC but adjusting the pick-up sensitivity has been different to what has been explained. Looking at my unit in the same way as the diagram on page 41, I adjusted VR2 as described but mine seems to work back-to-front, though my trimpot is facing the same way as in the diagram. I could only adjust Q7’s collector (top leg, just under the “Q7” label) to 4.44V max, not 5V plus the two extra turns as described. I drove the vehicle anyway and it seemed to run really well for approximately 15 minutes and then as I entered the freeway and accelerated, I suddenly got a lot of misfire and popping and the vehicle subsequently would only idle roughly. While stationary I tried to accelerate from idle but it stalled. I noticed while idling that the alternator cap sounded like there was a lot of unusual arcing going on inside that wasn’t there before. I switched back to the vehicle’s original ignition system which is working fine. I would really like some help as to what’s going on. (R. O., Balga, WA.) • The trimpot setting for the reluctor is possibly the problem. Try adjusting VR2 when the reluctor is warmed up or when the engine runs poorly. The 470pF capacitor connected across the reluctor may also need to be increased to remove any misfiring due to alternator noise. Try a 1nF or 2.2nF capacitor. Dual-channel audio delay unit wanted I have been searching the internet for audio delay modules. I’ve come across some projects in SILICON CHIP that look great. Can these be bought as a complete kit? I would want three or four of them. (D. H., via email.) • There are no kits for the DualChannel Audio Delay project from the November 2013 issue but we do have the PCB, the programmed micro and the codec IC available on our on-line shop at www.siliconchip.com.au/ SC Shop/?article=5450 Advertising Index AEE (ElectroneX)......................... 43 Allan Warren Electronics............ 111 Altronics.................................. 84-87 Control Devices Group................. 49 Digi-Key Electronics....................... 3 Electrolube (HK Wentworth)......... 46 Emona Instruments.................... IBC Front Panel Express..................... 15 Gless Audio.................................. 14 Glyn Ltd NZ.................................. 51 Hammond Manufacturing............. 44 Hare & Forbes.......................... OBC Jaycar .............................. IFC,53-60 KCS Trade Pty Ltd........................ 17 Keith Rippon Kit Assembly ........ 111 LD Electronics............................ 111 LEDsales.................................... 111 Master Instruments.................... 111 Mastercut Technologies................ 50 Microchip Technology................ 9,41 Minitech Engineering................... 10 Mouser Electronics......................... 7 Ocean Controls.............................. 8 PCB Cart...................................... 11 Pinfold Health Services................ 14 Rohde & Schwarz........................ 45 Rolec OKW.................................. 48 Sesame Electronics................... 111 SC Radio & Hobbies DVD.......... 109 SC Online Shop.................. 100-101 Silicon Chip Binders................... 106 Silicon Chip Wallchart.................. 39 Silvertone Electronics.................. 15 Tecsun Radios Australia................. 5 Tronixlabs.............................. 13,111 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 Competition & Consumer Act 2010 or as subsequently amended and to any governmental regulations which are applicable. 112  Silicon Chip siliconchip.com.au