Build Your Own Vintage Radio Broadcaster
The Elektor AM Transmitter Kit allows streaming audio to vintage AM radio receivers. Based on a Raspberry Pi Pico microcontroller module, the AM Transmitter can transmit on 32 frequencies in the AM band, from 500 kHz up to 1.6 MHz in 32 steps of approx. 35 kHz.
The frequency is selected with a potentiometer and shown on a 0.96" OLED display. A pushbutton allows toggles the transmitting mode between On and Off. The range of the transmitter depends on the antenna. The onboard antenna provides a range of a few centimeters, requiring the AM Transmitter to be placed close to or inside the radio. An external loop antenna (not included) can be connected to increase the range.
The Elektor AM Transmitter Kit comes as a kit of parts that you must solder to the board yourself.
Features
The board is compatible with a Hammond 1593N enclosure (not included).A 5 VDC power supply with micro-USB connector (e.g., an old phone charger) is needed to power the kit (not included). Current consumption is 100 mA.
The Arduino software (requiring Earle Philhower’s RP2040 Boards Package) for the Elektor AM Transmitter Kit plus more information is available at the Elektor Labs page of this project.
Component List
Resistors
R1, R4 = 100 Ω
R2, R3, R8 = 10 kΩ
R5, R6, R9, R10, R11 = 1 kΩ
R7 = optional (not included)
P1 = potentiometer 100 kΩ, linear
Capacitors
C1 = 22 µF 16V
C2, C4 = 10 nF
C3 = 150 pF
Miscellaneous
K1 = 4×1 pin socket
K2, K3 = 3.5 mm socket
Raspberry Pi Pico
pushbutton, angle mount
0.96" monochrome I²C OLED display
PCB 150292-1
The Elektor Super Servo Tester can control servos and measure servo signals. It can test up to four servo channels at the same time.
The Super Servo Tester comes as a kit. All the parts required to assemble the Super Servo Tester are included in the kit. Assembling the kit requires basic soldering skills. The microcontroller is already programmed.
The Super Servo Tester features two operating modes: Control/Manual and Measure/Inputs.
In Control/Manual mode the Super Servo Tester generates control signals on its outputs for up to four servos or for the flight controller or ESC. The signals are controlled by the four potentiometers.
In Measure/Inputs the Super Servo Tester measures the servo signals connected to its inputs. These signals may come from for instance an ESC, a flight controller, or the receiver or another device. The signals are also routed to the outputs to control the servos or the flight controller or ESC. The results are shown on the display.
Specifications
Operating modes
Control/Manual & Measure/Inputs
Channels
3
Servo signal inputs
4
Servo signal outputs
4
Alarm
Buzzer & LED
Display
0.96' OLED (128 x 32 pixels)
Input voltage on K5
7-12 VDC
Input voltage on K1
5-7.5 VDC
Input current
30 mA (9 VDC on K5, nothing connected to K1 and K2)
Dimensions
113 x 66 x 25 mm
Weight
60 g
Included
Resistors (0.25 W)
R1, R3
1 kΩ, 5%
R2, R4, R5, R6, R7, R9, R10
10 kΩ, 5%
R8
22 Ω, 5%
P1, P2, P3, P4
10 kΩ, lin/B, vertical potentiometer
Capacitors
C1
100 µF 16 V
C2
10 µF 25 V
C3, C4, C7
100 nF
C5, C6
22 pF
Semiconductors
D1
1N5817
D2
LM385Z-2.5
D3
BZX79-C5V1
IC1
7805
IC2
ATmega328P-PU, programmed
LED1
LED, 3 mm, red
T1
2N7000
Miscellaneous
BUZ1
Piezo buzzer with oscillator
K1, K2
2-row, 12-way pinheader, 90°
K5
Barrel jack
K4
1-row, 4-way pin socket
K3
2-row, 6-way boxed pinheader
S1
Slide switch DPDT
S2
Slide switch SPDT
X1
Crystal, 16 MHz
28-way DIP socket for IC2
Elektor PCB
OLED display, 0.96', 128 x 32 pixels, 4-pin I²C interface
Links
Elektor Magazine
Elektor Labs
Whatever the methods or even then financial means you have to make your circuits work, the power supply should rank high if not Number One in your considerations. The design block simply called “power supply” is hugely underrated both in electronics creation and repair. Yet, the “PSU” has enormous diversity and comes in wildly differing guises like AC/DC, generator, battery (rechargeable or not), PV panel, benchtop, linear or switch-mode, to mention but a few. The output ranges are also staggering like nano-amps to kiloamps and the same for voltages.This special covers the features and design aspects of power supplies.ContentsBasics
Battery ManagementWhat to be aware of when using (Lithium) batteries.
Fixed-Voltage Power Supply using Linear RegulatorsThe best result right after batteries.
Light Energy HarvestingA small solar panel is used in an energy harvesting project to manage and charge four AAA cells.
Mains Powered Adapter DesignBasic circuits and tips for transformers, rectification, filtering and stabilization.
LM317 Soft StartThe high inrush current pulse should be avoided.
Controllable RectifiersSome suggestions to keep the power loss in the linear regulator as low as possible.
Components
Worksheet: The LM117 / LM217 / LM317 Voltage Regulators
SupercapsLow voltage but lots of current… or not?
Reviews
JOY-iT RD6006 Benchtop Power Supply Kit
Siglent SDL1020X Programmable DC Electronic Load
Projects
Balcony Power PlantDIY solar balcony = speedy payback!
DIY LiPo Supercharger KitFrom handcrafted to mass market
Dual-Anode MOSFET ThyristorFaster and less wasteful than the old SCR
Battery JuicerDo not throw away, squeeze!
High-Voltage Power Supply with Curve TracerGenerate voltages up to 400 V and trace characteristics curves for valves and transistors
High Voltage Supply for RIAAFor RIAA tube preamps and other applications.
MicroSupplyA lab power supply for connected devices
Phantom Power Supply using Switched CapacitorsVoltage tripler using three ICs
The SMPS800RE Switch-Mode Supply for the Elektor Fortissimo-100Reliable, light and affordable
Soft Start for PSUBe nice to your power supply – and its load
UniLab 20-30 V, 3 A compact switch-mode lab power supply
Tips
Soft Start for Step-Down Switching Regulators
Low Loss Current Limit
Powerbank Surprise
A Virtual Ground
Battery Maintainer
Battery Pack Discharger
Connecting Voltage Regulators in Parallel
More than 275 Power Supply Designs for Home Construction
This USB Stick contains over 275 different power supply circuits from the volumes 2001-2025 of Elektor. The article search feature allows you to search full-text content. The results are always displayed as pre-formatted PDF documents.
Highlights
Cuk Converter
Automatic Battery Switchover
Battery Voltage LED
Digital Benchtop Power Supply
Lithium-Ion Charger
Solar Cell Charger
Electronic Fuse
High Voltage Regulator
Power Supply for USB Devices
Step-up Converter for LEDs
Battery Management
and much more...
On the Stick you will also find a folder with additional material such as PCB layouts, Gerber files and software.
Specifications
Storage
16 GB
Interfaces
1x USB-A1x USB-C
System requirements
PC with Adobe Reader 7.0 or higher
Web browser
As demand for solar panel installation has risen sharply, especially for installations larger than balcony power plants, the order books of solar companies are full. If you ask for a quote today, you may have to wait a while, if your request isn't simply postponed indefinitely. Another consequence of the solar boom is that some companies are charging very high prices for installations.
Yet there is an obvious and radical solution to the problem of excessive prices: Do it yourself, as the English say. The price of materials is currently affordable, and it's the ideal time for those who do the work themselves. They couldn't save more. Add to this the satisfaction of doing something useful, both economically and ecologically, and the pleasure of building yourself.
In this special issue, you'll find a wide selection of Elektor assemblies, from solar panel controllers to solar water heaters and solar panel orientation systems. The issue also contains practical information on solar panel installation and the technology behind them. Finally, there are a number of articles on the subject of balcony power plants, from how to install them to how to connect them to the Internet...
Contents
BASICS
Dimensioning Photovoltaic Panel ArraysAn introduction to photovoltaic energy and the commonest techniques,followed by simplified calculation models and setup guidelines.
Light Sensor TechnologyMeasuring daylight using LEDs.
Solar Power Made SimpleSolar charging with and without a controller.
Cable Cross-sections and Energy Losses in Solar SystemsKey considerations on the minimum values to respect for electricalcurrent in solar panel cabling.
Solar ModulesEverything you always wanted to know about solar panels...
Ideal Diode ControllerDiode Circuits with Low Power Dissipation.
TIPS
Tracking for Solar Modules
zBot Solar/Battery Power Supply
Solar Cell Array Charger with Regulator
Solar Cell Voltage Regulator
Solar-Powered Night Light
Alternative Solar Battery Charger
PROJECTS
Energy LoggerMeasuring and Recording Power Consumption.
Tiny Solar SupplySunlight In, 3.3 V Out.
A Do-It-Yourself DTURead Data from Small Inverters by μC.
Solar ChargerPortable energy for people on the move.
Solar Thermal Energy RegulatorMaximum power point tracking explored.
2-amp Maximum Power Tracking ChargerSolar Power To The Max.
Computer-driven HeliostatFollow the sun or the stars.
Garden LightingUsing solar cells.
Solar Panel Voltage Converter for IoT DevicesYes we CAN exploit indoor lighting.
Travel ChargerFree power in the mountains.
Solar Cell Battery Charger/MonitorWith protection against deep discharge.
Solar-powered Battery ChargerPIC12C671 avoids overcharging and deep charging.
Converters for Photovoltaic PanelsContributed by TME (Transfer MultisortElektronik).
Solar Charging RegulatorFor panels up to 53 watts.
Solar-Powered ChargerFor lead-acid batteries.
CAN Bus + Arduino for Solar PV Cell MonitoringDetect and locate serviceable panels in large arrays.
Balcony Power Plant 2.0The latest: solar panels, installation and inverters
Pull Down Lever For Highest Score!
This Elektor Circuit Classic from 1984 shows a playful application of CMOS 400x series logic ICs in combination with LEDs, a highly popular combination at the time. The project imitates a spinning-digit type slot machine.
The Game
To play the game, first agree on the number of rounds. Player 1 actuates the switch lever as long as desired and releases it. The LEDs then show the score which is the sum of the 50-20-10-5 digits lit up. If the Play Again! LED lights, Player 1 has another, “free” round. If not, it’s Player 2’s turn. The players keep tab of their scores, and the highest score wins.
Features
LEDs Indicate Score
Multi-Player and Play Again!
Elektor Heritage Circuit Symbols
Tried & Tested by Elektor Labs
Educational & Geeky Project
Through-Hole Parts Only
Included
Printed Circuit Board
All Components
Wooden Stand
Bill of Materials
Resistors (5%, 250 mW)
R1,R2,R3,R4 = 100kΩ
R5,R6,R7,R8,R9,R10 = 1kΩ
Capacitors
C1 = 4.7nF, 10%, 50V, 5mm
C2 = 4.7μF, 10%, 63V, axial
C3,C4 = 100nF, 10 %, 50V, ceramic X7R, 5mm
Semiconductors
LED1-LED6 = red, 5mm (T1 3/4)
IC1 = 74HC4024
IC2 = 74HC132
Miscellaneous
S1 = switch, toggle, 21mm lever, SPDT, momentary
S2 = switch, tactile, 24V, 50mA, 6x6mm
S3 = switch, slide, SPDT
IC1,IC2 = IC socket, DIP14
BT1 = PCB-mount CR2032 battery retainer clip
Desktop Stand
PCB 230098-1
Not included: BT1 = CR2032 coin cell battery
The Elektor MultiCalculator Kit is an Arduino-based multifunction calculator that goes beyond basic calculations. It offers 22 functions including light and temperature measurement, differential temperature analysis, and NEC IR remote control decoding. The Elektor MultiCalculator is a handy tool for use in your projects or for educational purposes.
The kit features a Pro Mini module as the computing unit. The PCB is easy to assemble using through-hole components. The enclosure consists of 11 acrylic panels and mounting materials for easy assembly. Additionally, the device is equipped with a 16x2 alphanumeric LCD, 20 buttons, and temperature sensors.
The Elektor MultiCalculator is programmable with the Arduino IDE through a 6-way PCB header. The available software is bilingual (English and Dutch). The calculator can be programmed with a programming adapter, and it is powered through USB-C.
Modes of Operation
Calculator
4-Ring Resistor Code
5-Ring Resistor Code
Decimal to Hexadecimal and Character (ASCII) conversion
Hexadecimal to Decimal and Character (ASCII) conversion
Decimal to Binary and Character (ASCII) conversion
Binary to Decimal and Hexadecimal conversion
Hz, nF, capacitive reactance (XC) calculation
Hz, µH, inductive reactance (XL) calculation
Resistance calculation of two resistors connected in parallel
Resistance calculation of two resistors connected in series
Calculation of unknown parallel resistor
Temperature measurement
Differential temperature measurement T1&T2 and Delta (δ)
Light measurement
Stopwatch with lap time function
Item counter
NEC IR remote control decoding
AWG conversion (American Wire Gauge)
Rolling Dice
Personalize startup message
Temperature calibration
Specifications
Menu languages: English, Dutch
Dimensions: 92 x 138 x 40 mm
Build time: approx. 5 hours
Included
PCB and though-hole components
Precut acrylic sheets with all mechanical parts
Pro Mini microcontroller module (ATmega328/5 V/16 MHz)
Programming adapter
Waterproof temperature sensors
USB-C cable
Downloads
Software
The Elektor Milliohmmeter Adapter uses the precision of a multimeter to measure very low resistance values. It is an adapter that converts a resistance into a voltage that can be measured with a standard multimeter.
The Elektor Milliohmmeter Adapter can measure resistances below 1 mΩ using a 4-wire (Kelvin) method. It is useful for locating short circuits on printed circuit boards (PCB).
The adapter features three measurement ranges – 1 mΩ, 10 mΩ, and 100 mΩ – selectable via a slide switch. It also includes onboard calibration resistors. The Elektor Milliohmmeter Adapter is powered by three 1.5 V AA batteries (not included).
Specifications
Measurement ranges
1 mΩ, 10 mΩ, 100 mΩ, 0.1%
Power supply
3x 1.5 V AA batteries (not included)
Dimensions
103 x 66 x 18 mm (compatible with Hammond 1593N-type enclosure, not included)
Special feature
On-board calibration resistors
Downloads
Documentation
,
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Discover four of Elektor’s most exciting electronics kits — from IoT and Arduino to retro logic and motion control. Whether you're just starting out or...