| Circuit | Category | Date Added | OK? | Votes | |
| 4 channel 433MHz remote control transmitter / receiver based on SM5162 and SM5172 chips | RF | |  | 14 |
|
| SCA Adapter - listen to advertisement free background music on FM broadcast radio | RF | Sep 23, 2009 | | 6 |
|
| Experimental DSB/CW QRP rig for 20 and 40 meter bands (PDF) | RF | Oct 05, 2009 | | 0 |
|
| Simple 40 meters CW QRP Transceiver (PDF) | RF | Oct 05, 2009 | | 1 |
|
| 20 meters CW QRP Transceiver (PDF) | RF | Oct 05, 2009 | | -3 |
|
| USB 0-500MHz RF Power Meter based on a AD8307 | RF | Feb 21, 2013 | | -3 |
|
| Simple FM receiver based on a TEA5591 IC | RF | Mar 23, 2015 | | -6 |
|
| Electronic Eavesdropping Devices Detector | RF | Jun 26, 2009 | | 1 |
|
| Radio Wave Alarm | RF | Jun 26, 2009 | | 1 |
|
| Linear FM 50Watt with BLY90 | RF | Jun 28, 2009 | | -4 |
|
| Send Morse on your VHF Rig | RF | | | -1 |
|
| An end-fed antenna, L-match coupler and resistive bridge for HF | RF | | | -3 |
|
| Regenerative receiver for the AM broadcast band using two transistors | RF | | | 0 |
|
| Novel crystal set requires no antenna, earth | RF | | | 1 |
|
| 80 meter direct conversion receiver | RF | | | 0 |
|
| A compact L-match ATU for portable use | RF | | | 0 |
|
| Converter to yune six metres on your two metre receiver | RF | | | 0 |
|
| High quality AM through your FM stereo | RF | | | -2 |
|
| Converter to Hear Amateurs on your FM Radio | RF | | | 0 |
|
| RF Actuated Keying Monitor | RF | | | 0 |
|
| LF to HF Converter | RF | | | -3 |
|
| Super 80 ultra-simple SSB receiver for 3.5 MHz a basic superhet | RF | | | -1 |
|
| 50 MHz to 10 MHz receive converter | RF | Jun 19, 2011 | | 1 |
|
| 17M to 6M transveter circuit diagram | RF | Jun 19, 2011 | | -1 |
|
| metre receiver | RF | Jun 19, 2011 | | -2 |
|
| T-Match ATU (antenna tuning unit) | RF | Jun 19, 2011 | | -2 |
|
| Single transistor receiver for SSB, CW, AM using a VHF dual gate MOSFET | RF | Jun 19, 2011 | | 0 |
|
| Multi band SSB transceiver construction project | RF | Jun 19, 2011 | | -1 |
|
| Receiver building blocks | RF | Sep 06, 2001 | | 2 |
|
| Digital display and VFO stabiliser using a PIC microcontroller and LCD | RF | Jun 19, 2011 | | 1 |
|
| SSB transceiver for 80M | RF | Jun 19, 2011 | | -1 |
|
| VHF receiver converterer | RF | | | -1 |
|
| Circuit diagrams for 418/433 MHz short-range communication (Elektor Electronics article) | RF | Apr 12, 2014 | | 3 |
|
| Circuit diagram for superregenerative receiver built by GE labs | RF | Apr 12, 2014 | | -3 |
|
| X10 RF daughter board - receiver circuit diagram | RF | Apr 12, 2014 | | 0 |
|
| RX3302 433MHz superregenerative receiver module circuit diagram | RF | Apr 12, 2014 | | -1 |
|
| Automicro RX3304 receiver module schematic | RF | Apr 12, 2014 | | 1 |
|
| 49MHz walkie-talkie circuit diagram that uses only three transistors | RF | Apr 12, 2014 | | 5 |
|
| Superregenerative 27MHz receiver | RF | Mar 23, 2003 | | 0 |
|
| Montreal Doppler 3 DF (direction finder) unit | RF | Apr 14, 2011 | | 1 |
|
| Construction details for 30 meter rig with superhet receiver and crystal controlled transmitter | RF | Apr 12, 2014 | | 0 |
|
| All Discrete Components 40 M transceiver with super-het receiver using no IC's | RF | Apr 12, 2014 | | -1 |
|
| Versatile L tuner for end feed wire antennas that fits in an Altoids tin. | RF | Apr 12, 2014 | | 0 |
|
| MMR-40 40 meter rig with SSB (voice) and CW (Morse code) operating modes. | RF | Apr 12, 2014 | | 1 |
|
| An 80 meter rig for the MAS contest by KD1JV | RF | Apr 12, 2014 | | 1 |
|
| A unique PSK transceiver, Version 2 By Steven Weber, KD1JV | RF | Apr 12, 2014 | | -2 |
|
| (Fairly) Simple 75M SSB rig with PTT | RF | Apr 12, 2014 | | 2 |
|
| AM Short Wave Broadcast Receiver circuit diagram | RF | | | -3 |
|
| Universal USB digimode interface supports CAT (Yaesu), CI/V (Icom) and RS-232 (Kenwood) units (PDF) | RF | Oct 07, 2009 | | -1 |
|
| Convert 2m VHF FM PMR transceiver Motorola Radius M110 into an amateur radio | RF | Jun 18, 2003 | | 0 |
|
| Simple CW identifier for a FM repeater (PDF) | RF | Oct 07, 2009 | | -1 |
|
| 6m SSB & CW QRP transceiver | RF | Oct 07, 2009 | | -1 |
|
| 80m SSB & CW QRP superhet transceiver | RF | Oct 07, 2009 | | 2 |
|
| Pocket sized 20m (30m) CW QRP transceiver | RF | Oct 07, 2009 | | 0 |
|
| USB / CAT (CI-V) adapter tested with FT-8900, FTB-9800, VX-7R, VX-7, FT-817 and IC-706MkIIG | RF | Oct 07, 2009 | | 1 |
|
| Wideband SWR meter | RF | | | 0 |
|
| SCA Subcarrier Demodulator for FM broadcast stations | RF | | | 1 |
|
| 118MHz to 136MHz aircraft receiver circuit diagram | RF | Jul 03, 2011 | | 3 |
|
| Shortwave received circuit diagram | RF | Jul 03, 2011 | | -2 |
|
| Beat frequency oscillator for AM/SW radio receivers | RF | May 25, 2012 | | 0 |
|
| Direct conversion 7MHz receiver using NE602 | RF | May 25, 2012 | | 0 |
|
| WWV receiver | RF | May 25, 2012 | | 2 |
|
| 1.5 GHz PLL Frequency Synthesizer | RF | Apr 10, 2014 | | 0 |
|
| Transverter for Converting SSB CB to LF for Thru-the-Earth Voice Communications | RF | Mar 03, 2011 |  | 2 |
|
| Simple ADS-B aircraft transponder decoder based on a PIC18F2550 microcontroller | RF | Dec 09, 2010 | | 2 |
|
| Active RF antennuator | RF | Apr 14, 2011 | | 2 |
|
| Simple Time-Difference-Of-Arrival RDF | RF | Apr 14, 2011 | | 0 |
|
| 555 Time-Difference-Of-Arrival RDF | RF | Apr 14, 2011 | | -1 |
|
| 50MHz converter project based on a NE602/SA602/NE612 | RF | | | 0 |
|
| HF/6M Antenna Tuner Preselector and Antenna Switcher | RF | | | 0 |
|
| MW Enhanced Crystal Receiver using 741 IC | RF | | | -2 |
|
| 455 Khz MF to AF converter used for DRM reception in a Yaesu FRG-100 receiver | RF | | | 1 |
|
| Sensitive LW/MW/SW Shortwave general coverage receiver | RF | | | -1 |
|
| MW/SW Radio receiver | RF | | | 0 |
|
| Bipolar transistor RF mixer | RF | | | -1 |
|
| HF/VHF mini portable antenna tuner | RF | | | 0 |
|
| RF Power meter / dummy load | RF | | | 1 |
|
| SWR bridge covering HF to VHF | RF | | | 1 |
|
| HF/VHF portable antenna tuner | RF | | | -1 |
|
| Aircraft Radio Communications Receiver | RF | Sep 01, 2009 | | -1 |
|
| Crystal Radio | RF | Sep 01, 2009 | | 1 |
|
| Class B series modulator | RF | | | -1 |
|
| Build a Crystal Set (simple AM radio receiver) | RF | Apr 10, 2014 | | 2 |
|
| Precision Frequency Control for AM Radios - A Frequency Synthesized Local Oscillator | RF | Apr 10, 2014 | | 0 |
|
| DSP-RDF Doppler Radio Direction Finder circuit schematic - complete kit available | RF | Apr 14, 2011 | | 0 |
|
| 50O Load and Power Meter | RF | Feb 21, 2013 | | -1 |
|
| External antenna for the GPS-38, Magellan 2000, or Eagle Explorer GPS receivers | RF | May 01, 2004 | | 0 |
|
| 175KHz inductive pulse receiver (PDF) | RF | Jan 26, 2001 | | 2 |
|
| 200-400 MHz voltage controlled oscillator (PDF) | RF | Jan 26, 2001 | | -1 |
|
| Electronic Eavesdropping Devices Detector (bug detector) | RF | Feb 21, 2005 | | -2 |
|
| CB (27MHz citizens band) receiver | RF | Feb 21, 2005 | | -2 |
|
| AM BCB radio receiver | RF | Oct 23, 2002 | | 0 |
|
| Regenerative shortwave receiver | RF | Jun 08, 2002 | | -1 |
|
| RF front-end for triple conversion GPS receiver (PDF) | RF | Mar 01, 2003 | | 1 |
|
| 7MHz SSB Transceiver | RF | May 01, 2004 | | -1 |
|
| AM receiver circuit diagram | RF | Sep 08, 2009 | | 0 |
|
| inexpensive high speed microwave data link using an Alpha Gunnplexer for 10 Mbps data rate | RF | | | 0 |
|
| 15M CW Transceiver design | RF | | | 0 |
|
| 20 Meter CW Transceiver | RF | | | 2 |
|
| 30 Meter, Discrete Component CW Transceiver Built Manhattan-style | RF | | | 0 |
|
| K8IQY's Original 2N2/40 CW Transceiver Rig | RF | | | 0 |
|
| 40 to 6 Meter "No Tune" Transverter | RF | | | 0 |
|
| SW30+ 30 Meter CW Transceiver | RF | | | 0 |
|
| Wave Bubble self-tuning portable RF jammer | RF | | | 0 |
|
| Wave Bubble - A design for a self-tuning portable RF jammer | RF | Oct 12, 2009 | | 1 |
|
| Simple home made ADS-B receiver that takes IF from a modified receiver | RF | Oct 04, 2010 | | 1 |
|
| Very Simple ADSB Receiver using a TV tunder to allow reception of aircraft transponders | RF | Oct 04, 2010 | | 0 |
|
| 115200 RS232 QPSK RF modem project | RF | Oct 04, 2010 | | 0 |
|
| Yaesu FT-736R doppler compensation | RF | Aug 14, 2002 | | 0 |
|
| 30M PSK31 Transceiver circuit diagram | RF | Feb 25, 2003 | | 1 |
|
| SOP receiver (PDF) | RF | Oct 30, 2002 | | 2 |
|
| SOP direct conversion receiver | RF | Jan 06, 2002 | | -1 |
|
| Electroluminescent Receiver Kit includes circuit diagram | RF | | | 1 |
|
| Receiver based on NE602 | RF | Jan 26, 2001 | | 0 |
|
| DC40 - 40M Direct Conversion receiver | RF | Oct 08, 2009 | | -1 |
|
| Simple Dual Band SSB Transceiver (20/40 meters) | RF | Oct 08, 2009 | | -1 |
|
| 40m band direct conversion receiver | RF | Jan 06, 2002 | | 0 |
|
| 80m band direct conversion receiver | RF | Jan 06, 2002 | | -2 |
|
| Regenerative Short Wave Radio | RF | | | 0 |
|
| Homebrew 20m CW Transceiver | RF | | | -1 |
|
| Homebrew 30m CW Transceiver | RF | | | 1 |
|
| Homebrew 40m CW Transceiver | RF | | | 1 |
|
| Homebrew 6m SSB/CW Transceiver | RF | | | 0 |
|
| Homebrew 6m DSB Transceiver | RF | | | -1 |
|
| FPGA Based ADS-B Receiver and Decoder | RF | Dec 09, 2010 | | 0 |
|
| 136 kHz direct conversion receiver | RF | Jan 06, 2002 | | 0 |
|
| Audible S-Meter | RF | | | 0 |
|
| 40 Segment LED S-Meter circuit diagram | RF | | | 0 |
|
| 20 Watt GaAaFET Power on 2.3 GHz | RF | Jun 13, 2002 | | 0 |
|
| High Frequency VCO Design and Schematics | RF | Oct 25, 2014 | | 1 |
|
| Dopler RDF (radio direction finder) circuit | RF | | | 0 |
|
| VFO from 2001 ARRL Handbook, page 17.74 | RF | Nov 01, 2002 | | 1 |
|
| VFO from 2001 ARRL Handbook, page 14.20 | RF | Nov 01, 2002 | | 0 |
|
| Assorted RF circuits | RF | Mar 18, 2003 | | 0 |
|
| 14MHz SSB 10mW Transceiver | RF | Feb 24, 2003 | | 0 |
|
| VLF radio receiver schematic | RF | Apr 17, 2004 | | 4 |
|
| VLF Upconverter for Shortwave Receiver | RF | Sep 13, 2006 | | 0 |
|
| Basic Vox Circuit | RF | | | 0 |
|
| Variable Bandwidth CW Filter | RF | | | 0 |
|
| An Inexpensive Tone Encoder | RF | | | 0 |
|
| 5 watt, 80 meter QRP CW Transceiver | RF | Jun 08, 2002 | | 0 |
|
| Two Transistor Reflex Radio | RF | Aug 17, 2009 | | 1 |
|
| R2T2 Haywire Home Station | RF | Oct 07, 2009 | | 0 |
|
| ICOM CI-V interface with RS232 RTS to PTT | RF | May 01, 2004 | | 1 |
|
| Active Antenna AA-7 HF/VHF/UHF, 3-3000MHz | RF | | | -2 |
|
| Active antenna 1 to 20dB, 1-30 MHz range | RF | | | -1 |
|
| Active Antenna for AM-FM-SW | RF | | | -1 |
|
| FM radio active antenna | RF | | | -1 |
|
| Aviation band receiver | RF | | | -1 |
|
| Bug detector with beep using 7413 or 74LS13 | RF | Jan 26, 2001 | | 0 |
|
| Bug detector / countersurveillance monitor | RF | | | 0 |
|
| Basic RF oscillator | RF | Jan 26, 2001 | | -2 |
|
| Subcarrier adapter to listen to hidden subcarrier signals on FM radio | RF | | | 1 |
|
| Morse Code Beacon Keyer | RF | Sep 21, 2006 | | -1 |
|
| Improved FM Stereo Modulator | RF | Jul 09, 2002 | | 0 |
|
| QRP Antenna Tuner | RF | Sep 21, 2006 | | 0 |
|
| Smooth Tone Clickless CW Sidetone Generator | RF | Sep 21, 2006 | | 0 |
|
| High Fidelity FM Stereo Modulator (Rev E2) | RF | May 19, 2015 | | 0 |
|
| Variety of receiver converter projects | RF | Apr 24, 2001 | | 0 |
|
| One transistor FM receiver | RF | Apr 24, 2001 | | -1 |
|
| 42 Mc Band to 88 Mc Band (retrofit converter) Project | RF | Apr 24, 2001 | | -1 |
|
| RF noise bridge for HF | RF | | | -1 |
|
| 160m mini portable End Fed Half Wave Tuner - MkII | RF | | | 0 |
|
| Crystal radio circuits including diode performance comparison | RF | Mar 10, 2003 | | -1 |
|
| VK5JST Aerial analyser | RF | Jun 24, 2015 | | -1 |
|
| A dummy load and power meter for HF (PDF) | RF | Jun 24, 2015 | | 0 |
|
| Simple RIT circuit based on a 2N7000 FET | RF | Sep 01, 2009 | | -1 |
|
| 56K RF Modem circuit diagram | RF | Jan 06, 2002 | | -1 |
|
| Kenwood TR-7950 manual & schematics (PDF) | RF | Sep 10, 2006 | | 0 |
|
| Bug Duster - a detector for uncovering RF-based video and audio bugging devices | RF | Jul 10, 2015 | | -1 |
|
| Low Frequency Block Converter - Converts VLF/LF bands to shortwave frequencies | RF | Jul 10, 2015 | | 0 |
|
| Active antenna that will work from below a few kHz to over 100 MHz | RF | Jul 10, 2015 | | 0 |
|
| Programmable PLL (Si570) Local Oscillator for HF Receivers, Transmitters, Transceivers (PDF) | RF | Jul 13, 2015 | | -2 |
|
| All-purpose 0 - 30 MHz DDS VFO and Signal Generator based on the article by WB2V in QEX July, 1997. | RF | Jul 13, 2015 | | 0 |
|
| DDS based Signal Generator that runs from 1Hz to 60MHz in 1Hz steps | RF | Jul 13, 2015 | | 0 |
|
| DIY Dual Directional Coupler, 5 - 1000 MHz, 20 dB | RF | Jul 03, 2016 | | 1 |
|
| A universal VCO Board using a MC100EL1648DG and a PGA-103+ as buffer | RF | Jul 03, 2016 | | -1 |
|
| Mini RF frequency synthesizer using an MC12095 and MC12080 or MB 501 | RF | Jul 03, 2016 | | 1 |
|
| 10 kHz to10 GHz LED-Bargraph Power Meter - W1GHZ | RF | Jul 24, 2016 | | 3 |
|
| Variable PIN Attenuator 1dB to 20dB | RF | Sep 07, 2016 | | 0 |
|
| RF Activated Relay - W7ZOI | RF | Sep 07, 2016 | | 0 |
|
| 10 GHz Transceiver from a Radar Detector - WA5VJB | RF | Sep 28, 2016 | | 0 |
|
| 2 GHz to 10 GHz Cavity Multiplier | RF | Oct 17, 2016 | | 3 |
|
| 1 MHz to 1 GHz LED Absorption Meter - GW1TDV | RF | Oct 20, 2016 | | 0 |
|
| True Linear RF Power Detector | RF | Oct 20, 2016 | | 2 |
|
| 500 kHz to 3 GHz LED Field-Strength Meter | RF | Oct 20, 2016 | | 1 |
|
| 100 MHz - 2.5 GHz LED RF Signal Meter AD8313 | RF | Oct 20, 2016 | | 1 |
|