Next Month in Silicon Chip
Arduino LC Meter Shield
This kit from Altronics is based on Jim Rowe’s project in the June issue but has some changes to make it even
easier to use. It can be built into the MegaBox which we described this month, or into a separate laser-cut case.
nRF24L01+ 2.4GHz Wireless Data Transceiver Modules
Jim Rowe describes the operation of these 2Mbps digital radio modules with software that lets you communicate with a
pair of Arduino or Micromite modules. This article was held over in favour of the GY-68 and GY-BM modules in this month.
Easy-to-build Theremin has ten transistors
The eerie sound of the Theremin has featured in many movies from the distant past right up to the present. Why
not build this latest design from Silicon Chip which was first published almost 50 years ago? That means it uses
cheap and easy-to-get transistors and other bits (and no SMDs). You can take it to your next musical gig.
Touchscreen Controller for Induction Motor-based Lathes
This project uses a Micromite LCD BackPack along with our Induction Motor Speed Controller to drive a lathe. It
works with Induction Motors that have separate Start and Run windings and provides the ability to reverse the motor as well as control and monitor its speed.
Note: these features are prepared or are in preparation for publication and barring unforeseen circumstances, will be in
the next issue.
The January 2018 issue is due on sale in newsagents by Thursday, January 4th. Expect postal delivery of subscription
copies in Australia between January 2nd and January 16th.
Notes & Errata
Advertising Index
50A Charger Controller, November 2016: there is a discrepancy between the
circuit and PCB design. The circuit shows D4 connected between ground and
the junction of the 100kW and 22kW resistors, but on the PCB it is connected
to the wrong end of the 100kW resistor. We suggest constructors cut the track
and fix this with a wire link. The next batch of PCBs will have this flaw corrected.
Deluxe Touchscreen eFuse, July 2017: the text on page 47 (last paragraph,
third column) states that IC4 is connected... after D7. Instead, it is connected
after D1 and the associated 1W resistor.
Universal Battery Valve Power Supply, August 2017: the circuit on page 35 shows
the labelling on diodes D4 & D5 swapped. In other respects, the circuit is correct.
3-way Active Crossover for speakers, September & October 2017: the PCB
has pads for diode D4 but it was not shown on the PCB overlay or the circuit diagram because it isn’t strictly needed. It can be left off or fitted below D3 if desired.
Kelvin the Cricket, October 2017: The circuit on page 44 shows switch S1
connected to pin GP0/pin 7. It should connect to GP2/pin 5. The PCB is correct.
Modifications to Universal Battery Valve Power Supply, Circuit Notebook,
October 2017: there is a mistake in the circuit diagram which shorts out the
secondary of transformer T2 by joining pins 5 and 8. Diodes D5 and D6 should
connect to pin 5 of T2 only while diodes D4 and D7 and the 470µF capacitor
connect to pin 8 of T2.
6GHz+ Touchscreen Frequency Meter, October-December 2017: in the
first article on page 33 of the October 2017 issue, the parts list states that the
1PS70SB82 UHF diodes are supplied in the SOT-23 package. They are actually
in the smaller SOT-323 (SC-70) package. The board is designed to accept this.
Super-7 AM Radio, November 2017: there are two errors on the circuit of
page 49 & 49. Schottky diode D1 should be a BAT46, not BAT56. The capacitor
connected to the emitters of Q6 & Q7, the output coupling capacitor, is 470µF,
not 100µF. Also the parts list shows Q7, a BD140 as an NPN type. It is PNP, as
shown correctly on the circuit.
Finally, the text on page 47 has errors in two sentences: “It oscillates at a frequency set by the parallel resonant circuitry connected to its emitter, ie, the primary of T3 plus VC3 and VC4” and “the output signal of the mixer/oscillator appears at the bottom end of this secondary and is fed to the primary of transformer
T2”. The first sentence should refer to T2 while the second should refer to T3.
Altronics.................................. 74-77
Aussie Rechargeable Irons.......... 12
Dave Thompson......................... 103
Digi-Key Electronics....................... 3
Emona Instruments.................... IBC
Hare & Forbes.......................... OBC
High Profile Communications..... 103
Icom Pty Ltd................................. 13
Jaycar............................... IFC,49-56
Keith Rippon Kit Assembly......... 103
LEACH Co Ltd.............................. 33
LD Electronics............................ 103
LEDsales.................................... 103
Microchip Technology................... 11
Mouser Electronics......................... 7
Oatley Electronics........................ 10
Ocean Controls.............................. 8
PCBcart...................................... 41
Premier Batteries......................... 37
ROLEC OKW................................. 5
Sesame Electronics................... 103
SC Online Shop...................... 88-89
SC Radio, TV & Hobbies DVD...... 91
Silicon Chip Subscriptions.......... 83
The Loudspeaker Kit.com.............. 9
Tronixlabs................................... 103
Vintage Radio Repairs............... 103
Wagner Electronics...................... 63
104
Silicon Chip
Celebrating 30 Years
siliconchip.com.au
