Silicon ChipPartShop - December 2025 SILICON CHIP
  1. Contents
  2. Publisher's Letter: The lost art of backward compatibility
  3. Feature: Teach-In 2026 by Mike Tooley
  4. Subscriptions
  5. Project: Variable Speed Drive Mk2 for Induction Motors, Part 1 by Andrew Levido
  6. Feature: Audio Out by Jake Rothman
  7. Feature: Techno Talk by Max the Magnificent
  8. Feature: Max’s Cool Beans by Max the Magnificent
  9. Feature: The Fox Report by Barry Fox
  10. Feature: Circuit Surgery by Ian Bell
  11. Project: Digital Capacitance Meter by Stephen Denholm
  12. Feature: Net Work by Alan Winstanley
  13. Back Issues
  14. Project: Battery-Powered Model Train by Les Kerr
  15. PartShop
  16. Market Centre
  17. Advertising Index
  18. Back Issues

This is only a preview of the December 2025 issue of Practical Electronics.

You can view 0 of the 80 pages in the full issue.

Articles in this series:
  • Teach-In 12.1 (November 2025)
  • Teach-In 2026 (December 2025)
  • Teach-In 2026 (January 2026)
  • Teach-In 2026 (February 2026)
Items relevant to "Variable Speed Drive Mk2 for Induction Motors, Part 1":
  • Mk2 VSD PCB [11111241 or 9048-02] (AUD $15.00)
  • STM32G030K6T6 programmed for the VSD Mk2 [1111124A] (Programmed Microcontroller, AUD $10.00)
  • Firmware for the VSD Mk2 (Software, Free)
  • VSD Mk2 PCB pattern (PDF download) [11111241] (Free)
  • Mk2 VSD drilling & cutting diagrams (Panel Artwork, Free)
Articles in this series:
  • Variable Speed Drive Mk2, Part 1 (November 2024)
  • Variable Speed Drive Mk2, Part 2 (December 2024)
  • Variable Speed Drive Mk2 for Induction Motors, Part 1 (December 2025)
  • Variable Speed Drive Mk2 For Induction Motors, Part 2 (January 2026)
Articles in this series:
  • Audio Out (January 2024)
  • Audio Out (February 2024)
  • AUDIO OUT (April 2024)
  • Audio Out (May 2024)
  • Audio Out (June 2024)
  • Audio Out (July 2024)
  • Audio Out (August 2024)
  • Audio Out (September 2024)
  • Audio Out (October 2024)
  • Audio Out (March 2025)
  • Audio Out (April 2025)
  • Audio Out (May 2025)
  • Audio Out (June 2025)
  • Audio Out (July 2025)
  • Audio Out (August 2025)
  • Audio Out (September 2025)
  • Audio Out (October 2025)
  • Audio Out (November 2025)
  • Audio Out (December 2025)
  • Audio Out (January 2026)
  • Audio Out (February 2026)
Articles in this series:
  • Techno Talk (February 2020)
  • Techno Talk (March 2020)
  • (April 2020)
  • Techno Talk (May 2020)
  • Techno Talk (June 2020)
  • Techno Talk (July 2020)
  • Techno Talk (August 2020)
  • Techno Talk (September 2020)
  • Techno Talk (October 2020)
  • (November 2020)
  • Techno Talk (December 2020)
  • Techno Talk (January 2021)
  • Techno Talk (February 2021)
  • Techno Talk (March 2021)
  • Techno Talk (April 2021)
  • Techno Talk (May 2021)
  • Techno Talk (June 2021)
  • Techno Talk (July 2021)
  • Techno Talk (August 2021)
  • Techno Talk (September 2021)
  • Techno Talk (October 2021)
  • Techno Talk (November 2021)
  • Techno Talk (December 2021)
  • Communing with nature (January 2022)
  • Should we be worried? (February 2022)
  • How resilient is your lifeline? (March 2022)
  • Go eco, get ethical! (April 2022)
  • From nano to bio (May 2022)
  • Positivity follows the gloom (June 2022)
  • Mixed menu (July 2022)
  • Time for a total rethink? (August 2022)
  • What’s in a name? (September 2022)
  • Forget leaves on the line! (October 2022)
  • Giant Boost for Batteries (December 2022)
  • Raudive Voices Revisited (January 2023)
  • A thousand words (February 2023)
  • It’s handover time (March 2023)
  • AI, Robots, Horticulture and Agriculture (April 2023)
  • Prophecy can be perplexing (May 2023)
  • Technology comes in different shapes and sizes (June 2023)
  • AI and robots – what could possibly go wrong? (July 2023)
  • How long until we’re all out of work? (August 2023)
  • We both have truths, are mine the same as yours? (September 2023)
  • Holy Spheres, Batman! (October 2023)
  • Where’s my pneumatic car? (November 2023)
  • Good grief! (December 2023)
  • Cheeky chiplets (January 2024)
  • Cheeky chiplets (February 2024)
  • The Wibbly-Wobbly World of Quantum (March 2024)
  • Techno Talk - Wait! What? Really? (April 2024)
  • Techno Talk - One step closer to a dystopian abyss? (May 2024)
  • Techno Talk - Program that! (June 2024)
  • Techno Talk (July 2024)
  • Techno Talk - That makes so much sense! (August 2024)
  • Techno Talk - I don’t want to be a Norbert... (September 2024)
  • Techno Talk - Sticking the landing (October 2024)
  • Techno Talk (November 2024)
  • Techno Talk (December 2024)
  • Techno Talk (January 2025)
  • Techno Talk (February 2025)
  • Techno Talk (March 2025)
  • Techno Talk (April 2025)
  • Techno Talk (May 2025)
  • Techno Talk (June 2025)
  • Techno Talk (July 2025)
  • Techno Talk (August 2025)
  • Techno Talk (October 2025)
  • Techno Talk (November 2025)
  • Techno Talk (December 2025)
  • Techno Talk (January 2026)
  • Techno Talk (February 2026)
Articles in this series:
  • Max’s Cool Beans (January 2025)
  • Max’s Cool Beans (February 2025)
  • Max’s Cool Beans (March 2025)
  • Max’s Cool Beans (April 2025)
  • Max’s Cool Beans (May 2025)
  • Max’s Cool Beans (June 2025)
  • Max’s Cool Beans (July 2025)
  • Max’s Cool Beans (August 2025)
  • Max’s Cool Beans (September 2025)
  • Max’s Cool Beans: Weird & Wonderful Arduino Projects (October 2025)
  • Max’s Cool Beans (November 2025)
  • Max’s Cool Beans (December 2025)
  • Max’s Cool Beans (January 2026)
  • Max’s Cool Beans (February 2026)
Articles in this series:
  • The Fox Report (July 2024)
  • The Fox Report (September 2024)
  • The Fox Report (October 2024)
  • The Fox Report (November 2024)
  • The Fox Report (December 2024)
  • The Fox Report (January 2025)
  • The Fox Report (February 2025)
  • The Fox Report (March 2025)
  • The Fox Report (April 2025)
  • The Fox Report (May 2025)
  • The Fox Report (July 2025)
  • The Fox Report (August 2025)
  • The Fox Report (September 2025)
  • The Fox Report (October 2025)
  • The Fox Report (October 2025)
  • The Fox Report (December 2025)
  • The Fox Report (January 2026)
  • The Fox Report (February 2026)
Articles in this series:
  • STEWART OF READING (April 2024)
  • Circuit Surgery (April 2024)
  • Circuit Surgery (May 2024)
  • Circuit Surgery (June 2024)
  • Circuit Surgery (July 2024)
  • Circuit Surgery (August 2024)
  • Circuit Surgery (September 2024)
  • Circuit Surgery (October 2024)
  • Circuit Surgery (November 2024)
  • Circuit Surgery (December 2024)
  • Circuit Surgery (January 2025)
  • Circuit Surgery (February 2025)
  • Circuit Surgery (March 2025)
  • Circuit Surgery (April 2025)
  • Circuit Surgery (May 2025)
  • Circuit Surgery (June 2025)
  • Circuit Surgery (July 2025)
  • Circuit Surgery (August 2025)
  • Circuit Surgery (September 2025)
  • Circuit Surgery (October 2025)
  • Circuit Surgery (November 2025)
  • Circuit Surgery (December 2025)
  • Circuit Surgery (January 2026)
  • Circuit Surgery (February 2026)
Articles in this series:
  • Win a Microchip Explorer 8 Development Kit (April 2024)
  • Net Work (May 2024)
  • Net Work (June 2024)
  • Net Work (July 2024)
  • Net Work (August 2024)
  • Net Work (September 2024)
  • Net Work (October 2024)
  • Net Work (November 2024)
  • Net Work (December 2024)
  • Net Work (January 2025)
  • Net Work (February 2025)
  • Net Work (March 2025)
  • Net Work (April 2025)
  • Net Work (September 2025)
  • Net Work (November 2025)
  • Net Work (December 2025)
Practical Electronics PCB SERVICE PROJECT DECEMBER 2025 CODE PRICE Variable Speed Drive (black).................................................... 11111241 £11.99 Digital Capacitance Meter........................................................ 04111241 £5.99 Battery-Powered Model Train transmitter............................... 09110241 £3.99 Battery-Powered Model Train through-hole receiver.............. 09110242 £3.99 Battery-Powered Model Train SMD receiver........................... 09110243 £3.99 Battery-Powered Model Train battery charger........................ 09110244 £3.99 Transmanium Fuzz Box jack PCB........................................... AO-DEC-25 £3.99 NOVEMBER 2025 Capacitor Discharger............................................................... 9047-01 5MHz, 40A Current Probe........................................................ 9049-01 Transmanium Fuzz Box main PCB.......................................... AO-NOV-25 OCTOBER 2025 Seaside Sound Simulator PCB (blue)...................................... 01111241 Fender Jazz Bass pickguard................................................... 23109241 J&D Luthiers T-Style pickguard............................................... 23109242 Music Man Stingray pickguard................................................ 23109243 Fender Telecaster pickguard.................................................... 23109244 3D Printer Filament Dryer control PCB.................................... 28110241 £4.99 £5.99 £4.99 £7.99 £5.99 £5.99 £5.99 £4.99 £4.99 SEPTEMBER 2025 Automatic LQ Meter PCB........................................................ CSE240203A £5.99 Automatic LQ Meter front panel (black).................................. CSE240204A £5.99 Compact Hi-Fi Headphone Amplifier PCB (blue)................... 01103241 £4.99 Discrete Ideal Bridge Rectifier TH PCB................................... 18108241 £2.99 Discrete Ideal Bridge Rectifier SMD PCB............................... 18108242 £2.99 Dual Rail Supply Protector PCB.............................................. 18109241 £3.99 Audio Out Cascode Amplifier PCB......................................... CASCODEA £4.99 Audio Out Cascode Amplifier Power Supply PCB................. CASCODEP £4.99 AUGUST 2025 Micromite Explore-40 PCB...................................................... 07106241 Micromite Explore-40 Audio Breakout PCB........................... 07101222 8-Channel Learning IR Remote Receiver PCB....................... 15108241 FlexiDice PCB set..................................................................... 08107241-2 JULY 2025 Compact OLED Clock & Timer PCB....................................... 19101231 180-230V DC Motor Speed Controller PCB........................... 11104241 Mains Power-Up Sequencer PCB (same as Feb ‘25)............. 10108231 JUNE 2025 Styloclone (case version)......................................................... 23106241 Styloclone (standalone version)............................................... 23106242 Dual Mini LED Dice (TH LEDs, white solder mask)................. 08103241W Dual Mini LED Dice (TH LEDs, black solder mask)................. 08103241B Dual Mini LED Dice (SMD LEDs, white solder mask)............. 08103242W Dual Mini LED Dice (SMD LEDs, black solder mask)............. 08103242B Dual Hybrid Supply regulator board........................................ 18107211 Dual Hybrid Supply front panel control board......................... 18107212 Dual Hybrid Supply CPU board............................................... 01106193 Dual Hybrid Supply LCD adaptor............................................ 01106196 MAY 2025 Skill Tester 9000........................................................................ 08101241 USB-C Serial Adaptor (black solder mask)............................. 24106241 DC Supply Protector (SMD adjustable version)...................... 08106241 DC Supply Protector (TH adjustable version)......................... 08106242 DC Supply Protector (TH fixed version).................................. 08106243 APRIL 2025 ESR Test Tweezers PCB set.................................................... 04105241+ Fan Speed Controller Mk2....................................................... 10104241 Calibrated Microphone (SMD version).................................... 01108231 Calibrated Microphone (TH version)........................................ 01108232 £2.99 £2.99 £5.99 £4.99 £4.99 £9.99 £11.99 PROJECT MARCH 2025 CODE Pico Gamer............................................................................... 08104241 Compact Frequency Divider.................................................... 04112231 FEBRUARY 2025 Laser Communicator transmitter............................................. 16102241 Laser Communicator receiver.................................................. 16102242 Model Railway Points Controller transmitter........................... 09101241 Model Railway Points Controller receiver................................ 09101242 Mains Power-Up Sequencer.................................................... 10108231 JANUARY 2025 USB to PS/2 Converter for VGA PicoMite.............................. 07111231 ps2x2pico USB to PS/2 Converter.......................................... 07111232 Compact Microphone Preamplifier (case version).................. 01110231 Compact Microphone Preamplifier (integrated version)......... 01110232 £9.99 £2.99 £3.99 £3.99 £3.99 £9.99 £4.99 £3.99 £3.99 £3.99 £2.99 £11.99 £3.99 £3.99 £5.99 £5.99 DECEMBER 2024 Raspberry Pi Clock Radio PCB pair........................................ 19101241/2 £12.99 VGA PicoMite (blue)................................................................. 07107221 £5.99 Secure Remote Switch receiver.............................................. 10109231 £4.99 Secure Remote Switch transmitter (module version)............. 10109232 £2.99 Secure Remote Switch transmitter (discrete version)............. 10109233 £2.99 NOVEMBER 2024 Ideal Diode Bridge Rectifiers (28mm square).......................... 18101241 Ideal Diode Bridge Rectifiers (22mm square).......................... 18101242 Ideal Diode Bridge Rectifiers (4-pin SIL)................................. 18101243 Ideal Diode Bridge Rectifiers (tiny SOT-23)............................. 18101244 Ideal Diode Bridge Rectifiers (standalone SMD)..................... 18101245 Ideal Diode Bridge Rectifiers (standalone TH; 2oz copper)... 18101246 Multi-channel Volume Control (volume PCB).......................... 01111221 Multi-channel Volume Control (control PCB).......................... 01111222 Multi-channel Volume Control (OLED PCB, black)................. 01111223 OCTOBER 2024 TQFP-32 Programming Adaptor............................................. 24108231 TQFP-44 Programming Adaptor............................................. 24108232 TQFP-48 Programming Adaptor............................................. 24108233 TQFP-64 Programming Adaptor............................................. 24108234 2m VHF FM Test Signal Generator.......................................... 06107231 SEPTEMBER 2024 £6.99 £7.99 £2.99 £2.99 £2.99 £2.99 £5.99 £2.99 £3.99 £2.99 PRICE PIC Programming Adaptor...................................................... 24105231 Salad Bowl Speaker crossover................................................ 01109231 AUGUST 2024 Arduino ESR Meter combined L/C-ESR................................. 04106182 Arduino ESR Meter separate ESR........................................... 04106183 Watering System Controller..................................................... 15110231 £3.99 £3.99 £3.99 £3.99 £4.99 £6.99 £4.99 £4.99 £4.99 £4.99 £4.99 £4.99 £4.99 £4.99 £4.99 £7.99 £9.99 £7.99 £11.99 JULY 2024 Dynamic NFC Tag (22 × 31mm)............................................... 06101231 £5.95 Dynamic NFC Tag (86 × 54mm)............................................... 06101232 £7.95 Reciprocal Frequency Counter................................................ CSE230101C £8.95 Reciprocal Frequency Counter front panel (black mask)....... CSE230102 £7.95 Pi Pico-based Thermal Camera............................................... 04105231 £6.95 JUNE 2024 Loudspeaker Test Jig............................................................... 04106231 £12.95 MAY 2024 £5.99 £4.99 £3.99 £3.99 GPS-Disciplined Oscillator....................................................... 04103231 £12.95 Dual RF Amplifier...................................................................... CSE220602A £5.95 Songbird ................................................................................... 08103231 £7.95 continued on page 78... PCBs for most recent PE/EPE constructional projects are available. From the July 2013 issue onwards, PCBs with eight-digit codes have silk screen overlays and, where applicable, are double-sided, have plated-through holes, and solder mask. They are similar to photos in the project articles. Earlier PCBs are likely to be more basic and may not include silk screen overlay, be single-sided, lack plated-through holes and solder mask. Always check price and availability in the latest issue or online. A large number of older boards are listed for ordering on our website. In most cases we do not supply kits or components for our projects. For older projects it is important to check the availability of all components before purchasing PCBs. Magazine back issues are available – see https://www.electronpublishing.com/product-category/pe-back-issues-print-and-digital/ Practical Electronics | December | 2025 75 Double-sided | plated-through holes | solder mask PROJECT APRIL 2024 CODE PRICE Basic RF Signal Generator....................................................... CSE221001 £8.99 Basic RF Signal Generator front panel (black solder mask)... CSE220902B £9.99 Silicon Chirp Cricket................................................................. 08101231 £7.99 Test Bench ‘Swiss Army Knife’................................................ 04110221 £9.99 MARCH 2024 Digital Volume Control Potentiometer SMD version............... 01101231 Digital Volume Control Potentiometer through-hole version.. 01101232 Advanced SMD Test Tweezers body....................................... 04106221 Advanced SMD Test Tweezers legs (pair)............................... 04106212 FEBRUARY 2024 Active Mains Soft Starter......................................................... 10110221 JANUARY 2024 Q Meter ................................................................................... CSE220701 Q Meter front panel (black solder mask)................................. CSE220704 Raspberry Pi Pico W BackPack.............................................. 07101221 DECEMBER 2023 Digital Boost Regulator............................................................ 24110224 Dual-Channel Power Supply for Breadboards........................ 04112221 Display Adaptor for the Breadboard PSU............................... 04112222 £8.95 £9.95 £6.95 £7.95 £10.95 £8.95 £7.95 £8.95 £8.95 £11.95 £9.95 NOVEMBER 2023 LC Meter Mk3........................................................................... CSE220503C £9.95 DC Supply Filter for vehicles.................................................... 08108221 £8.95 Discrete Audio Op Amp PCB................................................... AO1-JUL23 £9.95 Discrete Audio Op Amp PCB + essential components.......... AO2-JUL23 £17.95 OCTOBER 2023 Buck/Boost Charger Adaptor.................................................. 14108221 PIC Breakout Board for SOIC parts........................................ 24110225 PIC Breakout Board for DIP parts........................................... 24110222 AVR64DD32 Breakout board................................................... 24110223 Automatic Train Controller........................................................ 09109221 Chuff Sound module................................................................ 09109222 SEPTEMBER 2023 Mini LED Driver......................................................................... 16106221 New GPS-Synchronised Clock............................................... 19109221 £9.95 £5.95 £5.95 £5.95 £6.95 £6.95 JUNE 2023 Arduino Programmable Load................................................... 04105221 Buck-Boost LED Driver............................................................ 16103221 PRICE 500W Amplifier Module............................................................ see p.22, April 2023 Clipping Indicator (per channel)............................................... 01112211 £7.95 CD Welder Power Supply (one needed).................................. 29103221 £9.95 CD Welder Controller (one needed)......................................... 29103222 £9.95 CD Welder Energy Storage module (several needed)............ 29103223 £7.95 AO Universal Dual Op Amp Board........................................AO1-APR23 £9.95 AO Stereo RIAA precision passives kit for dual op amp.......AO2-APR23 £8.95 MARCH 2023 Pico BackPack......................................................................... 07101221 Semaphore Signal (controller).................................................. 09103221 Semaphore Signal (blade)........................................................ 09103222 FEBRUARY 2023 Tesla Coil driver board.............................................................. 26102221 Tesla Coil potentiometer board................................................ 26102222 Cooling Fan Controller & Loudspeaker Protector................... 01102221 Remote Gate Controller........................................................... 11009121 JANUARY 2023 Classic LED Metronome – 8-LED............................................ 23111211 Classic LED Metronome – 10-LED.......................................... 23111212 Multi-Channel Speaker Protector – 6 channel........................ 01101221 Multi-Channel Speaker Protector – 4 channel........................ 01101222 Remote Control Range Extender – IR-to-UHF....................... 15109212 £9.95 £7.95 £5.95 £9.95 £5.95 £8.95 £12.95 £7.95 £8.95 £9.95 £7.95 £5.95 For the many earlier PCBs that we stock please see the PE website: www.electronpublishing.com PE/EPE PCB SERVICE Order Code Project Quantity Price ......................................................... ......................................................... ......................................................... ......................................................... 110dB RF Attenuator............................................................... CSE211003 £9.95 Universal Battery Charge Controller (2023 update)................ 14107192 £9.95 Wide-Range OhmMeter........................................................... 04109221 £12.95 Multimeter Checker/Calibrator................................................ 04107221 CODE ......................................................... £7.95 £9.95 AUGUST 2023 JULY 2023 PROJECT APRIL 2023 £10.95 ......................................................... ......................................................... Name. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Address . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . £8.95 £8.95 ......................................................... Precision AM-FM DDS Signal Generator................................ CSE211002 £14.95 Improved SMD Test Tweezers programmed PIC.................... 0410621PIC £12.95 AO 2x-dual-to-quad through-hole (pack of five)..................... AO1-MAY23 £6.95 AO 2x-dual-to-quad SMD (pack of five).................................. AO2-MAY23 £6.95 AO 2x-single-to-dual through-hole (pack of five).................... AO3-MAY23 £6.95 AO 2x-single-to-dual SMD (pack of five)................................ AO4-MAY23 £6.95 Tel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Email . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Card No . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Valid From . . . . . . . . . . . . . . . . . Expiry Date . . . . . . . . . . . . . . . Card Security No . . . . . . . . . . MAY 2023 You can also order PCBs by phone, email or via the shop on our website: www.electronpublishing.com No need to cut your issue – a copy of this form is just as good! All prices include VAT and UK p&p. Add £4 per project for post to Europe; £5 per project outside Europe. Orders and payment should be sent to: Practical Electronics, Electron Publishing Ltd 113 Lynwood Drive, Merley, Wimborne, Dorset BH21 1UU Tel 07918 614662 Email: pe<at>pemag.au Online Shop: www.electronpublishing.com Sorry, cheques cannot be accepted as we are based in Australia and our UK bank account does not allow cheque deposits. NOTE: Most boards are in stock and sent within seven days of order receipt. Please allow up to 28 days delivery if we need to restock. 78 Practical Electronics | December | 2025