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Notes & Errata The Majestic Loudspeaker System (June & September 2014): constructors should be aware that there were a number of errors in the June 2014 issue on building the Majestic Loudspeaker which were corrected in the September 2014 issue. For example, there was confusion over the size of the gap between the angled panel and rear panel; its specified 1.5mm width is correct but this results in a gap area of 6.3cm2, not 63cm2 as stated in the original article. In addition, the acoustic wadding used in the prototype is acrylic, not BAF and some of the dimensions in Fig.5 were wrong or missing. Corrected diagrams were published in the September issue. Also note that the horn used in the original prototype, as specified in the June 2014 issue, is no longer available so constructors will need to use the better Celestion horn as explained in the September update. Finally, some readers have been unable to purchase the eTone type 1525 woofer. While this would still be our preferred part, the Celestion 28/ FTR15-4080FD woofer is a valid alternative. This will fit in the same cut-out and has greater power handling capability. It costs more than Advertising Index the eTone woofer but may be easier to obtain. 6-Digit Nixie Clock, Mk2 (February & March 2015): an error was found in the routine which applies the time zone offset. This results in the clock displaying hour 24 rather than 00 after midnight. It can also result in an incorrect hour display for the first minute of each hour in time zones with a halfhour or quarter-hour offset. The latest version of the firmware (1910215D.hex), available on our website, fixes both problems. Users affected by these bugs can mail their PIC32 chip to our PO Box along with a return address for re-programming (be sure to specify that the chip is for the Nixie Clock). Low-cost, Accurate Voltage/Current/Resistance Reference (August 2015): the caption for the PCB photos on page 43 is wrong. If diode D1 is fitted, its cathode goes to the positive battery terminal, not its anode. The photo shows the correct orientation. PICAXE-Based Mains Timer, Circuit Notebook (August 2015): the circuit shows D1-D2 as 1N4148s. D1-D5 are all 1N4004 types. Altronics.................................. 74-77 Aust. Exhibitions & Events............ 40 Control Devices Group................. 47 Element14......................loose insert Electrolube................................... 43 Embedded Logic Solutions.......... 46 Emona Instruments...................... 45 Front Panel Express....................... 9 Hare & Forbes............................. 2-3 Hammond Manufacturing............. 44 Harbuch Electronics..................... 13 Icom Australia.............................. 12 Jaycar .............................. IFC,53-60 KCS Trade Pty Ltd........................ 11 Keith Rippon .............................. 111 Keysight Technologies.............. OBC LD Electronics............................ 111 LEDsales.................................... 111 Mastercut Technologies................ 43 Master Instruments........................ 7 Microbee Technology................... 71 Microchip Technology................ 5,89 Mikroelektronika......................... IBC Ocean Controls............................ 10 Qualieco Circuits Pty Ltd.............. 50 Questronix.................................. 111 Rohde & Schwarz........................ 51 Rolec OKW............................. 42,46 Ask SILICON CHIP . . . continued from page 111 position the total emitter resistance switches from 0.05Ω to 0.105Ω. This will produce pulse current figures of 8.6A, 14A and 20A for the three range positions of S2 and all four Mosfets SC will still be sharing the current. Next Issue Sesame Electronics................... 111 The October 2015 issue of SILICON CHIP is due on sale in newsagents by Thursday 24th September. Expect postal delivery of subscription copies in Australia between September 23rd and October 6th. Silicon Chip Subscriptions......... 110 Silicon Chip Online Shop........... 101 Silvertone Electronics.................. 73 Threadboard................................. 69 Tronixlabs................................... 111 Virtins Technology.......................... 8 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