There are 187 circuit schematics available in this category. Click here for all circuit diagrams. The Last circuit was added on Saturday, January 28, 2023.Please note some adblockers will suppress the schematics as well as the advertisement so please disable if the schematic list is empty.

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CircuitCategoryDate AddedOK?Votes 
4 channel 433MHz remote control transmitter / receiver based on SM5162 and SM5172 chipsRF Status13 vote up vote down
SCA Adapter - listen to advertisement free background music on FM broadcast radioRFSep 23, 2009Status6 vote up vote down
Experimental DSB/CW QRP rig for 20 and 40 meter bands (PDF)RFOct 05, 2009Status0 vote up vote down
Simple 40 meters CW QRP Transceiver (PDF)RFOct 05, 2009Status1 vote up vote down
20 meters CW QRP Transceiver (PDF)RFOct 05, 2009Status-3 vote up vote down
USB 0-500MHz RF Power Meter based on a AD8307RFFeb 21, 2013Status-3 vote up vote down
Simple FM receiver based on a TEA5591 ICRFMar 23, 2015Status-6 vote up vote down
Electronic Eavesdropping Devices DetectorRFJun 26, 2009Status1 vote up vote down
Radio Wave AlarmRFJun 26, 2009Status1 vote up vote down
Linear FM 50Watt with BLY90RFJun 28, 2009Status-4 vote up vote down
Send Morse on your VHF RigRF Status-1 vote up vote down
An end-fed antenna, L-match coupler and resistive bridge for HFRF Status-3 vote up vote down
Regenerative receiver for the AM broadcast band using two transistorsRF Status0 vote up vote down
Novel crystal set requires no antenna, earthRF Status1 vote up vote down
80 meter direct conversion receiverRF Status0 vote up vote down
A compact L-match ATU for portable useRF Status0 vote up vote down
Converter to yune six metres on your two metre receiverRF Status0 vote up vote down
High quality AM through your FM stereoRF Status-2 vote up vote down
Converter to Hear Amateurs on your FM RadioRF Status0 vote up vote down
RF Actuated Keying MonitorRF Status0 vote up vote down
LF to HF ConverterRF Status-3 vote up vote down
Super 80 ultra-simple SSB receiver for 3.5 MHz a basic superhetRF Status-1 vote up vote down
50 MHz to 10 MHz receive converterRFJun 19, 2011Status1 vote up vote down
17M to 6M transveter circuit diagramRFJun 19, 2011Status-1 vote up vote down
metre receiverRFJun 19, 2011Status-2 vote up vote down
T-Match ATU (antenna tuning unit)RFJun 19, 2011Status-2 vote up vote down
Single transistor receiver for SSB, CW, AM using a VHF dual gate MOSFETRFJun 19, 2011Status0 vote up vote down
Multi band SSB transceiver construction projectRFJun 19, 2011Status-1 vote up vote down
Receiver building blocksRFSep 06, 2001Status2 vote up vote down
Digital display and VFO stabiliser using a PIC microcontroller and LCDRFJun 19, 2011Status1 vote up vote down
SSB transceiver for 80MRFJun 19, 2011Status-1 vote up vote down
VHF receiver convertererRF Status-1 vote up vote down
Circuit diagrams for 418/433 MHz short-range communication (Elektor Electronics article)RFApr 12, 2014Status3 vote up vote down
Circuit diagram for superregenerative receiver built by GE labsRFApr 12, 2014Status-3 vote up vote down
X10 RF daughter board - receiver circuit diagramRFApr 12, 2014Status0 vote up vote down
RX3302 433MHz superregenerative receiver module circuit diagramRFApr 12, 2014Status-1 vote up vote down
Automicro RX3304 receiver module schematicRFApr 12, 2014Status1 vote up vote down
49MHz walkie-talkie circuit diagram that uses only three transistorsRFApr 12, 2014Status5 vote up vote down
Superregenerative 27MHz receiverRFMar 23, 2003Status0 vote up vote down
Montreal Doppler 3 DF (direction finder) unitRFApr 14, 2011Status1 vote up vote down
Construction details for 30 meter rig with superhet receiver and crystal controlled transmitterRFApr 12, 2014Status0 vote up vote down
All Discrete Components 40 M transceiver with super-het receiver using no IC'sRFApr 12, 2014Status-1 vote up vote down
Versatile L tuner for end feed wire antennas that fits in an Altoids tin.RFApr 12, 2014Status0 vote up vote down
MMR-40 40 meter rig with SSB (voice) and CW (Morse code) operating modes.RFApr 12, 2014Status1 vote up vote down
An 80 meter rig for the MAS contest by KD1JVRFApr 12, 2014Status1 vote up vote down
A unique PSK transceiver, Version 2 By Steven Weber, KD1JVRFApr 12, 2014Status-2 vote up vote down
(Fairly) Simple 75M SSB rig with PTTRFApr 12, 2014Status2 vote up vote down
AM Short Wave Broadcast Receiver circuit diagramRF Status-3 vote up vote down
Universal USB digimode interface supports CAT (Yaesu), CI/V (Icom) and RS-232 (Kenwood) units (PDF)RFOct 07, 2009Status-1 vote up vote down
Convert 2m VHF FM PMR transceiver Motorola Radius M110 into an amateur radioRFJun 18, 2003Status0 vote up vote down
Simple CW identifier for a FM repeater (PDF)RFOct 07, 2009Status-1 vote up vote down
6m SSB & CW QRP transceiverRFOct 07, 2009Status-1 vote up vote down
80m SSB & CW QRP superhet transceiverRFOct 07, 2009Status2 vote up vote down
Pocket sized 20m (30m) CW QRP transceiverRFOct 07, 2009Status0 vote up vote down
USB / CAT (CI-V) adapter tested with FT-8900, FTB-9800, VX-7R, VX-7, FT-817 and IC-706MkIIGRFOct 07, 2009Status1 vote up vote down
Wideband SWR meterRF Status0 vote up vote down
SCA Subcarrier Demodulator for FM broadcast stationsRF Status1 vote up vote down
118MHz to 136MHz aircraft receiver circuit diagramRFJul 03, 2011Status3 vote up vote down
Shortwave received circuit diagramRFJul 03, 2011Status-2 vote up vote down
Beat frequency oscillator for AM/SW radio receiversRFMay 25, 2012Status0 vote up vote down
Direct conversion 7MHz receiver using NE602RFMay 25, 2012Status0 vote up vote down
WWV receiverRFMay 25, 2012Status2 vote up vote down
1.5 GHz PLL Frequency SynthesizerRFApr 10, 2014Status0 vote up vote down
Transverter for Converting SSB CB to LF for Thru-the-Earth Voice CommunicationsRFMar 03, 2011Status2 vote up vote down
Simple ADS-B aircraft transponder decoder based on a PIC18F2550 microcontrollerRFDec 09, 2010Status2 vote up vote down
Active RF antennuatorRFApr 14, 2011Status2 vote up vote down
Simple Time-Difference-Of-Arrival RDFRFApr 14, 2011Status0 vote up vote down
555 Time-Difference-Of-Arrival RDFRFApr 14, 2011Status-1 vote up vote down
50MHz converter project based on a NE602/SA602/NE612RF Status0 vote up vote down
HF/6M Antenna Tuner Preselector and Antenna SwitcherRF Status0 vote up vote down
MW Enhanced Crystal Receiver using 741 ICRF Status-2 vote up vote down
455 Khz MF to AF converter used for DRM reception in a Yaesu FRG-100 receiverRF Status1 vote up vote down
Sensitive LW/MW/SW Shortwave general coverage receiverRF Status-1 vote up vote down
MW/SW Radio receiverRF Status0 vote up vote down
Bipolar transistor RF mixerRF Status-1 vote up vote down
HF/VHF mini portable antenna tunerRF Status0 vote up vote down
RF Power meter / dummy loadRF Status1 vote up vote down
SWR bridge covering HF to VHFRF Status1 vote up vote down
HF/VHF portable antenna tunerRF Status-1 vote up vote down
Aircraft Radio Communications ReceiverRFSep 01, 2009Status-1 vote up vote down
Crystal RadioRFSep 01, 2009Status1 vote up vote down
Class B series modulatorRF Status-1 vote up vote down
Build a Crystal Set (simple AM radio receiver)RFApr 10, 2014Status2 vote up vote down
Precision Frequency Control for AM Radios - A Frequency Synthesized Local OscillatorRFApr 10, 2014Status0 vote up vote down
DSP-RDF Doppler Radio Direction Finder circuit schematic - complete kit availableRFApr 14, 2011Status0 vote up vote down
50O Load and Power MeterRFFeb 21, 2013Status-1 vote up vote down
External antenna for the GPS-38, Magellan 2000, or Eagle Explorer GPS receiversRFMay 01, 2004Status0 vote up vote down
175KHz inductive pulse receiver (PDF)RFJan 26, 2001Status2 vote up vote down
200-400 MHz voltage controlled oscillator (PDF)RFJan 26, 2001Status-1 vote up vote down
Electronic Eavesdropping Devices Detector (bug detector)RFFeb 21, 2005Status-2 vote up vote down
CB (27MHz citizens band) receiverRFFeb 21, 2005Status-2 vote up vote down
AM BCB radio receiverRFOct 23, 2002Status0 vote up vote down
Regenerative shortwave receiverRFJun 08, 2002Status-1 vote up vote down
RF front-end for triple conversion GPS receiver (PDF)RFMar 01, 2003Status1 vote up vote down
7MHz SSB TransceiverRFMay 01, 2004Status-1 vote up vote down
AM receiver circuit diagramRFSep 08, 2009Status0 vote up vote down
inexpensive high speed microwave data link using an Alpha Gunnplexer for 10 Mbps data rateRF Status0 vote up vote down
15M CW Transceiver designRF Status0 vote up vote down
20 Meter CW TransceiverRF Status2 vote up vote down
30 Meter, Discrete Component CW Transceiver Built Manhattan-styleRF Status0 vote up vote down
K8IQY's Original 2N2/40 CW Transceiver RigRF Status0 vote up vote down
40 to 6 Meter "No Tune" TransverterRF Status0 vote up vote down
SW30+ 30 Meter CW TransceiverRF Status0 vote up vote down
Wave Bubble self-tuning portable RF jammerRF Status0 vote up vote down
Wave Bubble - A design for a self-tuning portable RF jammerRFOct 12, 2009Status1 vote up vote down
Simple home made ADS-B receiver that takes IF from a modified receiverRFOct 04, 2010Status1 vote up vote down
Very Simple ADSB Receiver using a TV tunder to allow reception of aircraft transpondersRFOct 04, 2010Status0 vote up vote down
115200 RS232 QPSK RF modem projectRFOct 04, 2010Status0 vote up vote down
Yaesu FT-736R doppler compensationRFAug 14, 2002Status0 vote up vote down
30M PSK31 Transceiver circuit diagramRFFeb 25, 2003Status1 vote up vote down
SOP receiver (PDF)RFOct 30, 2002Status2 vote up vote down
SOP direct conversion receiverRFJan 06, 2002Status-1 vote up vote down
Electroluminescent Receiver Kit includes circuit diagramRF Status1 vote up vote down
Receiver based on NE602RFJan 26, 2001Status0 vote up vote down
DC40 - 40M Direct Conversion receiverRFOct 08, 2009Status-1 vote up vote down
Simple Dual Band SSB Transceiver (20/40 meters)RFOct 08, 2009Status-1 vote up vote down
40m band direct conversion receiverRFJan 06, 2002Status0 vote up vote down
80m band direct conversion receiverRFJan 06, 2002Status-2 vote up vote down
Regenerative Short Wave RadioRF Status0 vote up vote down
Homebrew 20m CW TransceiverRF Status-1 vote up vote down
Homebrew 30m CW TransceiverRF Status1 vote up vote down
Homebrew 40m CW TransceiverRF Status1 vote up vote down
Homebrew 6m SSB/CW TransceiverRF Status0 vote up vote down
Homebrew 6m DSB TransceiverRF Status-1 vote up vote down
FPGA Based ADS-B Receiver and DecoderRFDec 09, 2010Status0 vote up vote down
136 kHz direct conversion receiverRFJan 06, 2002Status0 vote up vote down
Audible S-MeterRF Status0 vote up vote down
40 Segment LED S-Meter circuit diagramRF Status0 vote up vote down
20 Watt GaAaFET Power on 2.3 GHzRFJun 13, 2002Status0 vote up vote down
High Frequency VCO Design and SchematicsRFOct 25, 2014Status1 vote up vote down
Dopler RDF (radio direction finder) circuitRF Status0 vote up vote down
VFO from 2001 ARRL Handbook, page 17.74RFNov 01, 2002Status1 vote up vote down
VFO from 2001 ARRL Handbook, page 14.20RFNov 01, 2002Status0 vote up vote down
Assorted RF circuitsRFMar 18, 2003Status0 vote up vote down
14MHz SSB 10mW TransceiverRFFeb 24, 2003Status0 vote up vote down
VLF radio receiver schematicRFApr 17, 2004Status4 vote up vote down
VLF Upconverter for Shortwave ReceiverRFSep 13, 2006Status0 vote up vote down
Basic Vox CircuitRF Status0 vote up vote down
Variable Bandwidth CW FilterRF Status0 vote up vote down
An Inexpensive Tone EncoderRF Status0 vote up vote down
5 watt, 80 meter QRP CW TransceiverRFJun 08, 2002Status0 vote up vote down
Two Transistor Reflex RadioRFAug 17, 2009Status1 vote up vote down
R2T2 Haywire Home StationRFOct 07, 2009Status0 vote up vote down
ICOM CI-V interface with RS232 RTS to PTTRFMay 01, 2004Status1 vote up vote down
Active Antenna AA-7 HF/VHF/UHF, 3-3000MHzRF Status-2 vote up vote down
Active antenna 1 to 20dB, 1-30 MHz rangeRF Status-1 vote up vote down
Active Antenna for AM-FM-SWRF Status-1 vote up vote down
FM radio active antennaRF Status-1 vote up vote down
Aviation band receiverRF Status-1 vote up vote down
Bug detector with beep using 7413 or 74LS13RFJan 26, 2001Status0 vote up vote down
Bug detector / countersurveillance monitorRF Status0 vote up vote down
Basic RF oscillatorRFJan 26, 2001Status-2 vote up vote down
Subcarrier adapter to listen to hidden subcarrier signals on FM radioRF Status1 vote up vote down
Morse Code Beacon KeyerRFSep 21, 2006Status-1 vote up vote down
Improved FM Stereo ModulatorRFJul 09, 2002Status0 vote up vote down
QRP Antenna TunerRFSep 21, 2006Status0 vote up vote down
Smooth Tone Clickless CW Sidetone GeneratorRFSep 21, 2006Status0 vote up vote down
High Fidelity FM Stereo Modulator (Rev E2)RFMay 19, 2015Status0 vote up vote down
Variety of receiver converter projectsRFApr 24, 2001Status0 vote up vote down
One transistor FM receiverRFApr 24, 2001Status-1 vote up vote down
42 Mc Band to 88 Mc Band (retrofit converter) ProjectRFApr 24, 2001Status-1 vote up vote down
RF noise bridge for HFRF Status-1 vote up vote down
160m mini portable End Fed Half Wave Tuner - MkIIRF Status0 vote up vote down
Crystal radio circuits including diode performance comparisonRFMar 10, 2003Status-1 vote up vote down
VK5JST Aerial analyserRFJun 24, 2015Status-1 vote up vote down
A dummy load and power meter for HF (PDF)RFJun 24, 2015Status0 vote up vote down
Simple RIT circuit based on a 2N7000 FETRFSep 01, 2009Status-1 vote up vote down
56K RF Modem circuit diagramRFJan 06, 2002Status-1 vote up vote down
Kenwood TR-7950 manual & schematics (PDF)RFSep 10, 2006Status0 vote up vote down
Bug Duster - a detector for uncovering RF-based video and audio bugging devicesRFJul 10, 2015Status-1 vote up vote down
Low Frequency Block Converter - Converts VLF/LF bands to shortwave frequenciesRFJul 10, 2015Status0 vote up vote down
Active antenna that will work from below a few kHz to over 100 MHzRFJul 10, 2015Status0 vote up vote down
Programmable PLL (Si570) Local Oscillator for HF Receivers, Transmitters, Transceivers (PDF)RFJul 13, 2015Status-2 vote up vote down
All-purpose 0 - 30 MHz DDS VFO and Signal Generator based on the article by WB2V in QEX July, 1997.RFJul 13, 2015Status0 vote up vote down
DDS based Signal Generator that runs from 1Hz to 60MHz in 1Hz stepsRFJul 13, 2015Status0 vote up vote down
DIY Dual Directional Coupler, 5 - 1000 MHz, 20 dBRFJul 03, 2016Status1 vote up vote down
A universal VCO Board using a MC100EL1648DG and a PGA-103+ as bufferRFJul 03, 2016Status-1 vote up vote down
Mini RF frequency synthesizer using an MC12095 and MC12080 or MB 501RFJul 03, 2016Status1 vote up vote down
10 kHz to10 GHz LED-Bargraph Power Meter - W1GHZRFJul 24, 2016Status3 vote up vote down
Variable PIN Attenuator 1dB to 20dBRFSep 07, 2016Status0 vote up vote down
RF Activated Relay - W7ZOIRFSep 07, 2016Status0 vote up vote down
10 GHz Transceiver from a Radar Detector - WA5VJBRFSep 28, 2016Status0 vote up vote down
2 GHz to 10 GHz Cavity MultiplierRFOct 17, 2016Status3 vote up vote down
1 MHz to 1 GHz LED Absorption Meter - GW1TDVRFOct 20, 2016Status0 vote up vote down
True Linear RF Power DetectorRFOct 20, 2016Status2 vote up vote down
500 kHz to 3 GHz LED Field-Strength MeterRFOct 20, 2016Status1 vote up vote down
100 MHz - 2.5 GHz LED RF Signal Meter AD8313RFOct 20, 2016Status1 vote up vote down