Radio-frequency schematics (also see Transmitters)

• 1 Watt 2.3 GHz RF Amplifier Using a MRF2001
• 1.5 W RF Power Amplifier type class-C
• 10 meter (28MHz) band RF amplifier
• 10 MHz WWV Receiver
• 115200 RS232 QPSK RF modem project
• 118MHz to 136MHz aircraft receiver circuit diagram
• 1300MHz - 1500MHz antenna with amplifier based on two MAR-8 RF amplifiers
• 136 kHz direct conversion receiver
• 14MHz SSB 10mW Transceiver
• 15M CW Transceiver Design
• 160m mini portable End Fed Half Wave Tuner - MkII
• 175KHz inductive pulse receiver (PDF)
• 17M to 6M transveter
• 18 dB LT1253 DDS Amplifier
• 2.3 GHz Power Amplifiers
• 20 Meter CW Transceiver
• 20 meters CW QRP Transceiver (PDF)
• 20 Watt GaAaFET Power on 2.3 GHz
• 200-400 MHz voltage controlled oscillator (PDF)
• 20dB VHF Amplifier
• 222 MHz Transverter
• 23 dB Bipolar DDS Amplifier
• 2304 and 3456 MHz Power Amplifiers
• 2m (144MHz) Dual Gate FET Low Noise Amplifier
• 2N2222 40 Meter CW/DSB Transceiver
• 30 Meter, Discrete Component CW Transceiver Built Manhattan-style
• 30 W Digital Wattmeter for RF (0-500MHz)
• 30 watt FM linear amplifier
• 300 baud RF modem circuit schematic
• 30M Direct Conversion Receiver Project
• 30M PSK31 Transceiver
• 4 channel 433MHz remote control transmitter / receiver based on SM5162 and SM5172 chips
• 40 Meter Band Direct Conversion experimental receiver
• 40 Meter Popcorn Superhet Receiver
• 40 Segment LED S-Meter
• 40 to 6 Meter "No Tune" Transverter
• 40m band direct conversion receiver
• 42 Mc Band to 88 Mc Band (retrofit converter) Project
• 450-2000KHz AM receiver (ZN414)
• 455 Khz MF to AF converter used for DRM reception in a Yaesu FRG-100 receiver
• 45-860MHz Radio receiver based on UV916-tuner
• 49MHz walkie-talkie
• 5 tubes SSB QRP Transceiver for 20m Ham band
• 5 watt, 80 meter QRP CW Transceiver
• 50 MHz Receiver based on MC3372
• 50 MHz to 10 MHz receive converter
• 50MHz converter project based on a NE602/SA602/NE612
• 50MHz RF Power Amplifier using BFG97
• 50O Load and Power Meter
• 555 Time-Difference-Of-Arrival RDF
• 56K RF Modem
• 6 Meter SSB transceiver
• 60-120MHz FM receiver with AFC
• 60W Linear amplifier using IRF840 power MOSFET
• 60W RF linear amplifier using IRF840
• 6m SSB & CW QRP transceiver
• 73MHz remote controller hallogen light
• 75 Meter QRP SSB Transceiver
• 78-80 MHz Superfast Scanner using a DDS (direct digital sythesizer)
• 7MHz SSB Transceiver
• 80 Meter CW ARDF receiver
• 80 meter direct conversion receiver
• 80m band direct conversion receiver
• 80m SSB & CW QRP superhet transceiver
• A compact L-match ATU for portable use
• A Multimode Phasing Exciter for 1 to 500 MHz from ARRL (PDF)
• Active antenna 1 to 20dB, 1-30 MHz range
• Active Antenna AA-7 HF/VHF/UHF, 3-3000MHz
• Active Antenna Experiments
• Active Antenna for AM-FM-SW
• Active RF antennuator
• Advanced VHF power meter (PDF)
• Aircraft Radio Communications Receiver
• AM BCB radio receiver
• AM receiver circuit diagram
• AM receiver for aircraft communications
• AM Short Wave Broadcast Receiver circuit diagram
• AM to FM conveter
• AM/FM/SW active antenna
• AM-Receiver for Aircraft communication (118.250MHz)
• An end-fed antenna, L-match coupler and resistive bridge for HF
• An Inexpensive Tone Encoder
• Assorted RF circuits
• Audible S-Meter
• Aviation band receiver
• Basic 10GHz / 24GHz gunplexer / gunn diode control circuit (PDF)
• Basic RF oscillator
• Basic Vox Circuit
• Beat frequency oscillator for AM/SW radio receivers
• Bi-Directional 2.4 GHz One Watt Amplifier
• Bi-Directional 900Mhz One Watt Amplifier
• Bipolar transistor RF mixer
• Bootstrapping a Phase Locked Loop for Better Performance
• Broadcast-Band RF Amplifier
• Bug detector / countersurveillance monitor
• Bug detector with beep using 7413 or 74LS13
• Build a COS Detector to detect the presence of a carrier on a receiver
• Build a good GaAs FET preamp for 2 meters, 222MHz or 440MHz
• Car radio tunes the amateur bands
• Cascode 7 Experimental Receiver
• Cascode Hybrid-Based WWV Receiver for 5 MHz
• CB (27MHz citizens band) 2.5W transmitter
• CB (27MHz citizens band) receiver
• Class B series modulator
• Class E Power Amplifier Design (136KHz operating frequency)
• Compact 20 - A 14 MHz Direct Conversion Receiver
• Convert 2m VHF FM PMR transceiver Motorola Radius M110 into an amateur radio
• Converter to Hear Amateurs on your FM Radio
• Converter to yune six metres on your two metre receiver
• COR Carrier Delay timer / Hang Timer
• Crystal Radio
• Crystal radio circuits including diode performance comparison
• DC40 - 40M Direct Conversion receiver
• Deluxe Direct Conversion Reciever
• Digital display and VFO stabiliser using a PIC microcontroller and LCD
• Digitally tuned radio board to create an embedded FM radio controlled by a Mega128
• Direct conversion 7MHz receiver using NE602
• Direct Crystal radio receiver examples
• Dopler RDF (radio direction finder) circuit
• DSP-RDF Doppler Radio Direction Finder circuit schematic - complete kit available
• Electroluminescent Receiver Kit includes circuit diagram
• Electronic Eavesdropping Devices Detector
• Electronic Eavesdropping Devices Detector (bug detector)
• Experimental DSB/CW QRP rig for 20 and 40 meter bands (PDF)
• External antenna for the GPS-38, Magellan 2000, or Eagle Explorer GPS receivers
• FM radio active antenna
• Four channel RF remote control
• Four Channel Wireless Transmitter and Receiver using RF modules (PDF)
• FPGA Based ADS-B Receiver and Decoder
• Galvanic isolated CAT & audio interface for amateur radio
• GPS jammer
• HF 10 watt amplifier for 18MHz using a 2SC1969/2SC1944 transistor
• HF/6M Antenna Tuner Preselector and Antenna Switcher
• HF/VHF mini portable antenna tuner
• HF/VHF portable antenna tuner
• High quality AM through your FM stereo
• High-Performance Direct-Conversion Receivers from ARRL (PDF)
• High-Performance, Single-Signal Direct-Conversion Receivers for ARRL (PDF)
• Homebrew 20m CW Transceiver
• Homebrew 30m CW Transceiver
• Homebrew 40m CW Transceiver
• Homebrew 6m DSB Transceiver
• Homebrew 6m SSB/CW Transceiver
• How to Build a 300MHz AM, RF Remote Control System
• ICOM CI-V interface with RS232 RTS to PTT
• Improved AM-Receiver for Aircraft communication
• Improved FM Stereo Modulator
• inexpensive high speed microwave data link using an Alpha Gunnplexer for 10 Mbps data rate
• Junk Box NDB Low Pass Filter
• K8IQY's Original 2N2/40 CW Transceiver Rig
• Kenwood TR-7950 manual & schematics (PDF)
• KL 400 RF linear amplifier
• LF to HF Converter
• Linear FM 50 watt amplifier with BLY90
• Linear FM 50Watt with BLY90
• Low Frequency Circulator/Isolator Uses No Ferrite or Magnet (PDF)
• Low Power RF ID Transponder (PDF)
• MC13136 based narrow band receiver
• Medium Frequency TRF Receiver
• metre receiver
• MF and HF Receive Antenna Splitter
• Montreal Doppler 3 DF (direction finder) unit
• Morse Code Beacon Keyer
• Multi band SSB transceiver construction project
• Multiplier Generates Odd Harmonics (PDF)
• MW Enhanced Crystal Receiver using 741 IC
• MW/SW Radio receiver
• Novel crystal set requires no antenna, earth
• One transistor FM receiver
• One Watt 2.45 GHz Linear Amplifier using RF Micro Devices RF2126
• One watt class-C RF amplifier (PDF)
• Op Amp Radio
• Op-amp based radio receiver
• Op-Amp Radio
• Passive grid (tube based) linear amplifier
• Phase Locking and Tuning
• Phase-Locking ULNs for Optimum Performance
• PLL synthesized FM radio that can decode DTMF
• Pocket sized 20m (30m) CW QRP transceiver
• Popcorn Direct Conversion Main Frame
• PSK Transceiver - Unique transceiver design does not use a SSB transmitter
• QRP - Circuits for measuring RF Voltage, RF Current, RF Power, SWR
• QRP Antenna Tuner
• R2T2 Haywire Home Station
• Radio Wave Alarm
• Receive Loop Preamplifier for LF reception
• Receiver based on NE602
• Receiver building blocks
• Regenerative receiver for the AM broadcast band using two transistors
• Regenerative Short Wave Radio
• Regenerative shortwave receiver
• RF Actuated Keying Monitor
• RF front-end for triple conversion GPS receiver (PDF)
• RF Isolator Uses Differential Amplifiers
• RF noise bridge for HF
• RF Power Amplifier Module using Toshiba S-AV10H
• RF Power meter / dummy load
• RF preamp circuit diagrams
• RF Sniffer under 0.5MHz to above 500MHz
• RX3302 receiver module schematic
• SA602, SA612 RF Mixer
• SCA Adapter - listen to advertisement free background music on FM broadcast radio
• SCA Subcarrier Demodulator for FM broadcast stations
• Send Morse on your VHF Rig
• Sensitive LW/MW/SW Shortwave general coverage receiver
• Shortwave received circuit diagram
• Simple 40 meters CW QRP Transceiver (PDF)
• Simple ADS-B aircraft transponder decoder based on a PIC18F2550 microcontroller
• Simple CW identifier for a FM repeater (PDF)
• Simple Dual Band SSB Transceiver (20/40 meters)
• Simple home made ADS-B receiver that takes IF from a modified receiver
• Simple RIT circuit based on a 2N7000 FET
• Simple Time-Difference-Of-Arrival RDF
• Simple wireless radio data link
• Single transistor receiver for SSB, CW, AM using a VHF dual gate MOSFET
• Smooth Tone Clickless CW Sidetone Generator
• Some experiments with active or voltage probe antennas (VPA)
• SOP direct conversion receiver
• SOP receiver (PDF)
• SSB linear amplifier made from a bunch of 2N2218 transistors
• SSB Receiver / Exciter and Linear amp
• SSB transceiver for 80M
• Stacked Torroid VFO Experiments 2008
• Subcarrier adapter to listen to hidden subcarrier signals on FM radio
• Super 80 ultra-simple SSB receiver for 3.5 MHz a basic superhet
• Super improved AM-Receiver for Aircraft
• Super Scanner 45-860MHz with 0.01Hz stepsize
• Superior TV-tuner receiver 45-860MHz in 2500Hz step
• Superregenerative 27MHz receiver
• SW30+ 30 Meter CW Transceiver
• Switching Diode Frequency Doublers (PDF)
• SWR bridge covering HF to VHF
• The MRX-40 Mini Receiver (PDF)
• T-Match ATU (antenna tuning unit)
• TR1001 868.35 MHz Hybrid transceiver schematic
• Transverter for Converting SSB CB to LF for Thru-the-Earth Voice Communications
• Two Diode Odd-Order Multiplier
• Two Transistor Reflex Radio
• TX Module Combiners (copied from commercial circuits)
• UHF Preamplifier covers 450MHz - 800MHz based on MPSH10 / BF180 / BCY90
• Universal USB digimode interface supports CAT (Yaesu), CI/V (Icom) and RS-232 (Kenwood) units (PDF)
• USB / CAT (CI-V) adapter tested with FT-8900, FTB-9800, VX-7R, VX-7, FT-817 and IC-706MkIIG
• USB 0-500MHz RF Power Meter based on a AD8307
• Variable Bandwidth CW Filter
• Variety of receiver converter projects
• Very Simple ADSB Receiver using a TV tunder to allow reception of aircraft transponders
• VFO from 2001 ARRL Handbook, page 14.20
• VFO from 2001 ARRL Handbook, page 17.74
• VHF 6 Meterband RF amplifier
• VHF receiver converterer
• VLF radio receiver schematic
• VLF Upconverter for Shortwave Receiver
• Wave Bubble - A design for a self-tuning portable RF jammer
• Wave Bubble self-tuning portable RF jammer
• Wee Willy 75 Meter DSB Transceiver Project
• Wideband SWR meter
• Wideband VHF/UHF/SHF 22dB RF preamp with MAR-6 or MAR-8 (MSA-0885)
• WLW 500KW Transmitter Schematic
• WWV receiver
• Yaesu band decoder schematic
• Yaesu FT-736R doppler compensation