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The Four State QRP Group is pleased to offer these quality kits to the QRP community.
Click the links below for each kit's page, which includes design features, specifications, documentation, and ordering information.
All proceeds fund our annual Conference, OzarkCon.
Please SCROLL DOWN for all the kits, and thank you for supporting the Four State QRP Group.

NEW ! NMØS 4S-Cootie A single-lever CW key with quality and value that is unmatched in a kit. In true QRP tradition, it is a simple, inexpensive design that goes together quickly.

NEW ! NMØS CW-VOX This is an easy to build Voice-activated Morse. This device is a unique blend of technology and creativity that allows keying by voice ! It's designed for Morse Code operators who may be afflicted with limitations that make traditional keying methods challenging - or for the operator who wants to try something new and fun !

NMØS Key PRICE REDUCED This easy to build key - an attractive and useful key for your bench.

NEW ! NMØS Dummy Load This easy to build dummy load kit utilizes large SMT components. The kit includes on-board LEDs used to display power levels. The Dummy Load can handle up to 10W and will be a useful tool on your bench or in the field.

NMØS Cricket 20 The Cricket 20, designed by David Cripe NMØS, is the newest addition to the low cost entry level line,and a fun, minimalist CW transceiver for the 20 meter band. It is a real transceiver with TX/RX offset, full QSK, and a sidetone. It features a high quality PC Board, low parts count, excellent components for this design (MOSFETs), and a modern audio amp. Dave's famous etched spiral coils are included on the pc board, so there are NO TOROIDS to wind. Additionally a straight key is included on the board, just snap it off, mount it, and the whole rig is then self contained. Also included is an electronic keyer adapter. These are many many features for such a low parts count and inexpensive transceiver.

NA1MH Soup'er Up'er The Soup'er Up'er is an add-on accessory board for the Bayou Jumper that adds a sidetone for transmitting, receiver fine tuning, and the Hi-Per-Mite CW Filter - all on one board to enhance the useability of the Bayou Jumper. The Soup'er Up'er mounts on the bottom of the Bayou Jumper's circuit board and does not require cutting any traces.

N5IB Crystal Spotter Designed by Jim Giammanco, N5IB, the Crystal Spotter uses a classic Pierce oscillator circuit to produce a signal at the series resonant frequency of a quartz crystal. The signal can be heard in a nearby receiver without any electrical connection to the receiver. It is useful for locating a crystal's operating frequency in uncalibrated receivers, or for checking whether a crystal is active.

K1SWL Hilltopper 30 Dave Benson K1SWL, founder of the renown Small Wonder Labs, listened to you and has designed a 30 meter version of his winning Hilltopper 20 design. Four State QRP Group is honored to have been selected to kit the new transceiver. The Hilltopper 30 is a high performance CW transceiver for the 30M meter band. It is the perfect solution to your portable operation needs - small, lightweight, wide 30 meter frequency coverage and low current drain, extending the life of your portable power source. The receiver is adapted from K1SWL’s SW+ Series with minor modifications. A custom silk-screened PCB enclosure is included with the kit. No drilling or cutting required!

NMØS Cricket 40 The Cricket 40, designed by David Cripe NMØS, is the newest addition to the low cost entry level line,and a fun, minimalist CW transceiver for the 40 meter band. It is a real transceiver with TX/RX offset, full QSK, and a sidetone. It features a high quality PC Board, low parts count, excellent components for this design (MOSFETs), and a modern audio amp. Dave's famous etched spiral coils are included on the pc board, so there are NO TOROIDS to wind. Additionally a straight key is included on the board, just snap it off, mount it, and the whole rig is then self contained. Also included is an electronic keyer adapter. These are many many features for such a low parts count and inexpensive transceiver.

K1SWL Hilltopper 40 Dave Benson K1SWL, founder of the renown Small Wonder Labs, listened to you and has designed a 40 meter version of his winning Hilltopper 20 design. Four State QRP Group is honored to have been selected to kit the new transceiver. The Hilltopper 40 is a high performance CW transceiver for the 40M meter band. It is the perfect solution to your portable operation needs - small, lightweight, wide 40 meter frequency coverage and low current drain, extending the life of your portable power source. The receiver is adapted from K1SWL’s SW+ Series with minor modifications. A custom silk-screened PCB enclosure is included with the kit. No drilling or cutting required!

NMØS Murania Talk to anyone who was around during the Sputnik era and he will tell you how exciting it was when the first transistor radios were introduced. For the first time, you could have a portable radio that could slip into your pocket, and affordable enough that young people could take their music with them anywhere. The Four-State QRP Group has brought back the thrill of those days gone by with the Murania receiver ! Designed by David Cripe NM0S, this simple kit is the perfect starter project to get young people interested in our hobby or to bring back those warm memories gained listening to your first portable radio.

K1SWL Hilltopper 20 Dave Benson K1SWL, founder of the renown Small Wonder Labs, has come up with another winning design. Four State QRP Group is honored to have been selected to kit the new transceiver. The Hilltopper is a high performance CW transceiver for the 20M meter band. It is the perfect solution to your portable operation needs - small, lightweight, wide 20 meter frequency coverage and low current drain, extending the life of your portable power source. The receiver is adapted from K1SWL’s SW+ Series with minor modifications. A custom silk-screened PCB enclosure is included with the kit. No drilling or cutting required!

NMØS SSB-Mite The SSB-MITE, designed by David Cripe NMØS, is a high-performing SSB filter capable of being added to nearly any receiver The SSB-MITE uses simple analog signal-processing circuitry to provide highly effective audio filtering from a simple circuit. It is designed to be very versatile, have low parts count, be inexpensive, yet provide outstanding performance. This is a flexible design that can be used as a stand-alone unit driving headphones, earbuds, or speakers, or it can be easily integrated into an existing receiver needing additional filtering.

NMØS BUZZ-KILL If your receiver is plagued with 60 cycle, and all it's harmonics buzzing in your shack or favorite portable QTH, the BUZZ-KILL will save your sanity. From the creative mind of NMØS the BUZZ-KILL is a special audio filter that removes 60 cycle noise and all of its harmonics, beating them down 40 db or more - it kills the buzz !

AAØZZ EZKeyer II-i This version of the EZKeyer II is designated the "i" version, and is designed to install INSIDE a rig's enclosure. Building on the very popular EZKeyer series, this new Morse code memory keyer is intended to be built into existing rigs which don't have a keyer - or integrated into new projects. New small printed circuit boards, and a new 8 pin processor are featured. There are two versions, THRU-HOLE and SMT, both are the same price.

NMØS Super Simple CPO Looking for an inexpensive project to share with your children, scout troop, or church group, especially a group that you want to teach Morse Code? THIS IS IT! This rugged and Super Simple Code Practic Oscillator is the classic two-transistor astable multivibrator circuit, and is designed for young people, groups, and those new to electronics, soldering, and kit building. It is very easy to build, the parts are widely spaced on the pc board, has minimal parts count, and only two resistor values and one capacitor value.

NMØS 4S-Tuner This excellent random wire antenna tuner is the classic T-Match design which is known for wide matching range and smooth operation. Dave has added a nice wrinkle - the SWR indicater employs TWO leds, not the normally seen single red LED. A green one indicates output power with a red one indicating reflected power. The beauty of this arrangement is that the operator sees the output power peaking as the SWR goes down, just like a power meter with dual meters - very intuitive. Add this dandy little tuner to your portable ops go bag, or use it at home. It's equally at home on a picnic table, in a tent or camper, as well as on the operating desk in your shack.

AAØZZ EZKeyer III Building on the popular EZKeyer and EZKeyer II, this third generation very capable Morse Code keyer has some additional features - a beautiful new easy building enclosure, a smaller footprint, new more powerful PIC microcontroller, Speed Pot, larger message memories, new printed circuit board layout, and large push button switches. All connectors, switches, the speed pot, and components are board mounted, making the keyer completely self contained on the board. It has many of the features of a high end keyer while remaining inexpensive and very user friendly.

NMØS Ozark Patrol The Ozark Patrol is a two-band shortwave regenerative receiver, using only three NPN transistors in its circuit. It features a pre-drilled and silkscreened circuit board front panel, with a total of 38 through-hole components mounted on pads etched on the back of the panel. This style of PC board is known as a Pittsburg style board. Component values and reference numbers are silk screened by each part location making this kit an excellent first kit for any builder. The Ozark Patrol makes great shortwave receiver to introduce youngsters to the magic of Short Wave Listening.

K1SWL Freq-Mite Four State is very pleased to continue the availability of Dave Benson K1SWL's famous Freq-Mite frequency counter. Upon retirement, Dave graciously offered the kit to us to continue production. Along with his SW+ transceiver series, the Freq-Mite is one of his signature designs. The Freq-Mite provides audio frequency annunciation, and is intended to be installed as a frequency counter inside a rig. Thus providing an inexpensive alternative to an LCD display.

NMØS Hi-Per-Mite CW Filter The HI-PER-MITE is a HIgh-PERformance SMALL audio filter. It is designed to be very versatile, have low parts count, be inexpensive, yet provide outstanding performance. This is a flexible design that can be used as a stand-alone unit driving headphones, earbuds, or speakers, or it can be easily integrated into an existing receiver needing additional CW filtering, see manual for details.

The kits below are retired, however the documentation will remain available.

NMØS/ N5IB Bayou Jumper The Bayou Jumper is a modernized version of the famous Paraset spy radio. It retains that great retro look but with modernized circuitry. The name "Bayou Jumper" is a play on "Ocean Hopper", a famous regenerative receiver of a bygone era. With it's distinctive panel and wood box enclosure, it pays homage to the famous spy radios of WWII. The receiver covers all of the CW segment of 40 meters, and the transmitter is Crystal controlled. Two crystals are included. It has recently been improved by Jim and Dave.

NMØS Cric-Key The Cricket series consists of low cost entry level minimalist CW transceivers. This kit is designed to complement 4SQRP's popular CRICKET series of QRP transceivers with a useful and easy-to build keyer circuit. High quality, double sided printed circuit board construction is used, with solder mask and silk screened component reference designators. All components are through-hole for easy assembly. The CRIC-KEY can be constructed by beginners as well as experienced builders. Construction time is approximately 30 to 90 minutes, depending on experience level.

NMØS Nouveau 75A The Nouveau 75A is a 75 Meter, QRP AM voice transceiver designed by Dave Cripe, NMØS. This design is simple, yet full-featured, efficient, and easy-to-build. This kit utilizes a hybrid construction, with about 80% of its components pre-installed surface mount devices. The remaining components are large, through-hole connectors, controls, and power devices. The kit includes a pre-drilled, silk-screened enclosure made of PCB material. The finished result is an attractive, functional radio that is easy to assemble and operate.

WD5AGO Ozark 17 Designed by Tommy Henderson WD5AGO, the Ozark 17 is a CW transceiver kit for the 17 meter band. It features a VXO controlled superhet receiver and a separate VXO controlled transmitter, often called an RXTX rig. This design has built in RIT. Power output is approximately 1.5 watt. Both the receiver and transmitter are built on one single sided pc board. The design features excellent sensitivity and great performance. This is a SMT kit with just a couple leaded parts.
This is a difficult kit designed for very experienced builders. We do not recommend this for the beginning or average builder.

KØEMT EFHW If you like to tinker with electronics, swapping out parts and measuring results, these EFHW Antenna Experimenter Boards are for you. If you are looking to build a kit to try out an end fed antenna, you probably should look elsewhere.

4S-High Pass Filter Featuring the famous NMØS Spiral coils, it is a None Simpler design.. This High Pass Filter (HPF) is a must have for experimeters and those wishing to make sure their rig is legal. This kit is placed in-line with the antenna to knock down all signals below 3.5 MHz by at least 60 dB. The kit includes all the components to finish the build, including a beautiful jet black pcb enclosure - another NM0S hallmark. At 3"x 2"x 3" it will fit easily in your portable operating bag, and on your desk or workbench. It is a quick build and one you will find useful for years to come.

ZZRX-40 Receiver This simple receiver demonstrates how very few components can be assembled to make a functioning and usable HF receiver. Many receivers of similar design have been built from scratch and and kits. But the ZZRX-40 has a few wrinkles that the others may not. Incorporated into the design is the ability to easily choose an on board VXO or LC VFO - or an external VFO of your choice. The kit also includes AAØZZ's excellent silk screened and drilled enclosure design. Refer to the photo page for details. There are NO SMT parts to install, only through hole parts are used, making this an easy kit to build.

AAØZZ Enclosures Four State enclosures provide kit builders with another option to safely keep the kits you have spent so much time building. The copper-clad PC board construction provides better shielding and protection than plastic boxes; easier modification than expensive aluminum ones. Our enclosures make it easy to locate and drill control holes and display windows with a flat panel instead of a bulky box cabinet. All enclosure panels are already painted and small groves assures a tight placement to secure the sides and bottom panel with solder. The top is easily removed, and a front overhang of the top/sides makes your kit look like one of the more expensive commercially-built units.

NMØS Cricket 30 The Cricket 30, designed by David Cripe NMØS, is a low cost entry level, fun, minimalist CW transceiver for the 30 meter band. It is a real transceiver with TX/RX offset, full QSK, and a sidetone. It features a high quality PC Board, low parts count, excellent components for this design (MOSFETs), and a modern audio amp. Dave's famous etched spiral coils are included on the pc board, so there are NO TOROIDS to wind. Additionally a straight key is included on the board, just snap it off, mount it, and the whole rig is then self contained. Also included is an electronic keyer adapter. These are many many features for such a low parts count and inexpensive transceiver.

NMØS Cricket (improved version) The Cricket is a low cost entry level ,and fun, minimalist CW transceiver for the 80 meter band. It is a real transceiver with TX/RX offset, full QSK, and a sidetone. It features a high quality PC Board, low parts count, excellent components for this design (MOSFETs), and a modern audio amp. Dave's famous etched spiral coils are included on the pc board, so there are NO TOROIDS to wind. Additionally a straight key is included on the board, just snap it off, mount it, and the whole rig is then self contained. Also included is an electronic keyer adapter. These are many many features for such a low parts count and inexpensive transceiver.

NMØS 4S-Low Pass Filter Featuring the famous NMS Spiral coils, it is a None Simpler design.. This Low Pass Filter (LPF) is a must have for experimeters and those wishing to make sure their rig is legal. It's available in either an 80M or 40M version. The kit includes all the components to finish the build, including a beautiful jet black pcb enclosure - another NM0S hallmark. At 3"x 2"x 3" it will fit easily in your portable operating bag, and on your desk or workbench. It is a quick build, and has been chosen as the build session kit at OzarkCon 2015. The kit features the easy building Pittsburg style pc board, which also is a feature of the Ozark Patrol regenerative receiver kit.

NMØS Original Cricket The Cricket is a low cost entry level ,and fun, minimalist CW transceiver for the 80 meter band. It is a real transceiver with TX/RX offset, full QSK, and a sidetone. It features a high quality PC Board, low parts count, excellent components for this design (MOSFETs), and a modern audio amp. Dave's famous etched spiral coils are included on the pc board, so there are NO TOROIDS to wind. Additionally a straight key is included on the board, just snap it off, mount it, and the whole rig is then self contained. Also included is an electronic keyer adapter. These are many many features for such a low parts count and inexpensive transceiver.

NMØS Attenuator Originally designed for new Boy Scout hams to build and use, this kit was introduced at Ocon 2016. It is a simple 1 watt RF attenuator which is very useful for VHF Fox(transmitter) Hunting. When the hunter is close to the transmitter beacon, the signal overloads the receiver (usually a hand held) and an attenuator must be used to regain sensitivity for the final "pounce", this kit provides that attenuation. Most of the assembly rolves around assembling the PCB enclosure, and an experienced builder should have the whole kit assembled in 30 minutes

K8IQY Designer Dream Boards These PC boards were targeted at the DIY designer/builder who would like to construct their own RF or control designs using time tested bits of circuitry, already in a PC board environment. The boards facilitated the construction of many RF circuits including receiver, converters, transmitters, and etc. utilizing builder supplied parts.

K8IQY SS-40 Stable and Sensitive 40M Receiver The SS-40 high performance receiver is the latest design effort from Jim Kortge, K8IQY. SS stands for "Stable and Sensitive". It exhibits the signature IQY extremely quiet amplifier chain. A matched crystal IF filter provides a steep sided 500 cycle bandpass and outstanding opposite sideband rejection. Covering the 40M QRP "watering holes", a Super VXO provides 25-30 kHZ of smooth stable tuning.

K8IQY SS-40TX This well designed transmitter is a companion to K8IQY's highly regarded SS-40 receiver. It produces up to 9 watts (can be set to 5W)and uses a hefty, cool running MOSFET as a final. All parts are through hole lead parts.

K8IQY SAVXO Stand Alone VXO. SAVXO stands for Stand Alone Variable Crystal Oscillator. This is a Super VXO design which has it's origins in the Super VXO of the SS-40 receiver. It is crystal controlled yet combines frequency agility with smooth stable tuning. It is ideal for driving your NS-40 or other crystal controlled transmitter or recever. It can be used on any of the HF bands, and is also a great starting point for a transmitter strip of your own design.

NMØS Cyclone 40M Transceiver This innovative and simple transceiver is an improved version of Dave's QRP ARCI's 72 Part Challenge Design Contest entry in 2010. It has less than 100 components and even better performance than the original design! The kit features all through hole parts and easy assembly. The receiver is a superhet design with very good sensitivity and selectivity, the VFO tunes the entire 125 kHZ CW segment of the 40M Band at a comfortable tuning rate.

K8IQY Magic Box TR Switching System The Magic Box is a solid state, all electronic, transmit/receive switching system that allows a separate receiver and transmitter to transceive with full (or semi) QSK. An Atmel Microcontroller handles the timing for 5 functions- xmttr keying, xmittr antenna switch, rcvr antenna switch, rcvr audio switch, and side tone oscillator.

NMØS QRPometer Power/SWR Meter This useful accessory is a highly accurate and easy to use power and swr indicating meter. All components are through-hole for easy assembly, and there NO toroids. It features a digital readout and a silk screened pcb front panel.

AAØZZ EZKeyer II Building on the very popular EZKeyer, this new and very capable Morse Code keyer has some additional features - a beautiful blue easy building enclosure, new PIC microcontroller, larger message memories, additional commands, new printed circuit board layout, and large panel mount push button switches. Additionally, all connectors and switches are board mounted, making the keyer completely self contained on the board. No external parts or wires are required (excepting battery leads).

NS-40 Class E Transmitter The NS-40 Transmitter is an upgraded version of the overall winner in the FDIM 2008 Homebrew Contest. It is a truly unique QRP transmitter design. NS stands for None Simpler, so this is the None Simpler 40 Meter Transmitter. Why is it called the None Simpler? Because there are only 14 electronic components, and NO TOROIDS or COILS of any kind to wind - NONE! All inductors are incorporated directly on the PC board as etched spirals.

NMØS 4S-Link Digital Interface The 4S-Link, pronounced "Force Link", is an easy to build, low parts count interface that connects your computer to the digital radio world. Attaching the 4S-Link to your computer is as easy as plugging into your sound card, a serial port or adapter is not required.

AAØZZ EZKeyer This full featured PIC-based iambic Morse code keyer features 3 memories and very easy use. It has been superceded by the EZKeyerII, see above.

NMØS Ham Can Minimalist Regen Transceiver The HAM CAN is a two transistor minimalist crystal-controlled CW transceiver.

Clear Top Tins Here are the perfect tins to show off and protect your home built projects.

NB6M HF Test Set The HF Test Set is a multi-function test instrument ideally suited for the QRP workbench.

NT7S VRX-1 Receiver A direct conversion receiver for 40 meters, but can be easily modifed for any band from 160 to 10 meters.

KD1JV Tenna Dipper The "Tenna Dipper" is a low power antenna analyzer and ATU tuning aid.

KD1JV Power and SWR Meter The KD1JV Power and SWR meter is a compact RF power and SWR measuring device for use in the shack or in the field.

K8IQY Enhanced Manhattan Islander Audio Amp The Enhanced Manhattan Islander Audio Amplifier is perfect for boosting the sound level from your headphone-only QRP rig.

Four State Dummy Load SMD Starter Kit The SMD Dummy Load is an easy way to learn SMD soldering techniques and finish with a handy addition to your test bench.

Updated: August 05, 2025

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