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WA3TFS Designs for Amateur Radio
Contact me at wa3tfs@arrl.net
On this site you can find additional information on projects of mine that have been published in QST Magazine and elsewhere including firmware downloads for those requiring it.
Contact me via e-mail if you have any questions.
All circuit boards are F4, double sided, mil spec with silkscreen and solder mask and plated through holes.
A SMALLNUMBER OF PARTIAL KITS FOR THIS TRANSCEIVER ARE NOW AVAILABLE !
Non USA addresses please add $16.00 USD Shipping
New Project now available. This is a CW QRP transceiver for 40 meters, 5 watts output with a high performance receiver having an adjustable bandwidth crystal filter, agc, and LCD color Display. This transceiver is featured in the December 2022 issue of QST Magazine. PC Boards are now available. All components are through-hole and mount on a single board.
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Non-USA addresses please add $14.00 Postage additional
SEE MANUAL , ABOVE, FOR ALL AMPLIFIER DETAILS
TWO VERSIONS OF THE AMPLIFIER SHOWN HERE. ABOVE ONE IS INSTALLED IN A BUD CU3003 BOX, THE BOTTOM ONE USES AN EXTRUDED ALUMINUM CASE. SW1 IS PWR, SW2 IS FAST/SLOW.
USE FOR CW, SSB AND DIGITAL MODES, CAN BE BUILT FOR OTHER HF BANDS WITH MINOR CHANGES. NOTE: With 13.7 volts and 5 watts drive typical output on 40 meters is 23 watts, on 80 meters, 34 watts output. 80 meter version requires different component values in LPF section only as shown in the manual.
NOTE: 80 meter build also usable on 160 meters and the 40 meter build is usable on 60 meters. 20 meter/17 meter version = 20+ watts out. Specify the band you want when ordering. Builder supplies enclosure, switches, connectors, etc. When active, RF input triggers antenna switching.
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Here is an article on how to build a simple variable inductor for pennies. This will tune your shortened antennas for portable or emergency use. Antenna wire length suggestions are included. This may eliminate the need for an antenna tuner. Great for POTA or other portable operation. Use for center or base loading.
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NOW AVAILABLE: QRP 20 WATT HF LINEAR AMPLIFIER BOARDS AND KITS. 5 WATTS IN = 20 WATTS OUT. 60/40 MTRS or 160/80 MTRS or 20/17 MTRS. (Board measures 2.75" x 3.25" Assembled height aproximately 1") Kit consists of board, all parts mounted on board plus printed 15 page manual. All through hole parts are used for easy assembly. Some parts values changes for 160/80 and 20/17 meter versions required.
SPECIFY THE BAND WHEN ORDERING. This amplifier can be used for CW, SSB, FM, AM or various Digital Modes such as FT8, RTTY, etc..
New PCB now available for the Simple AGC Circuit as featured in the August 2021 issue of QST----USE WITH THE SIMPLE RECEIVER OR ANY HOMEBREW RECEIVER
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6 OR 10 METER FM SDR TRANSCEIVER
An RTL dongle provides the receive function and the design utilizes inexpensive pre-assembled modules and amplifiers.
THIS DESIGN WAS FEATURED IN THE MARCH 2019 ISSUE OF QST MAGAZINE
AND AWARDED "BEST ARTICLE".
Kit consists of pcb and parts that mount on it. Not included is NANO module, DDS
Module, or buffer amp or enclosure. Also RTL dongle required for receive function.
CONNECTION WIRING DIAGRAM
FINAL CONFIGURATION
This transceiver uses an Arduino NANO and eBay DDS AD9850 module to generate FM digital modulation without mixing on six or 10 meter band. It will operate simplex or duplex mode and supports tone. All parts are through hole and the pre-assembled module and micro just plug onto the board.
CIRCUIT BOARDS ARE AVAILABLE, $25 for board, shipping included
Non USA address add $16
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1 kHz to 1.7 GHz SDR Receiver
This simple SDR up-converter/receiver will provide excellent performance over an extreme frequency range. Free HDSDR software allows you to control all demodulation specs and works on all modes
Assembled receiver for use with any computer or tablet
The design utilizes well designed front end filtering for rejection of commercial FM interference for outstanding performance. Receives CW, USB, LSB, NBFM, WBFM, AM
THIS DESIGN WAS FEATURED IN THE JANUARY 2016 ISSUE OF QST MAGAZINE AND AWARDED "BEST ARTICLE".
This board may be used to add a panadapter function to existing receivers. Just tap into the IF section.
The required SDR Dongle
This inexpensive dongle is used as the receiver function along with the free SDR software. All that is required for assembly is a few through hole parts.
CIRCUIT BOARDS AND KITS ARE AVAILABLE, $24.75 for the board, $55 for the kit, and $80 Assemble and tested.
(Note, Kits and Assembled include all parts that mount on the board but no RTL dongle) Shipping included in prices
Non-USA address add $16
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This analog audio notch filter and clipper also has an audio amplifier so it can function as a complete audio system for a home made receiver or can be installed with any older receiver lacking this function.
External controls allow you to set the notch frequency required across the entire audio spectrum, and set the level of clipping as necessary to limit noise bursts such as from distant lightning strikes. The notch, clipper and audio amplifier work independently or together as desired.
THIS DESIGN WAS FEATURED IN THE AUGUST 2015 ISSUE OF QST MAGAZINE
AND AWARDED "BEST ARTICLE".
Interconnection wiring diagram
CIRCUIT BOARDS ARE AVAILABLE, $10 for the board, shipping included
Non-USA address, add $16
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FRONT VIEW WITH ADDED NOTCH FILTER
This receiver is now published in MAY 2020 issue of QST
HF CW/SSB RECEIVER
WITH ADJUSTABLE BANDWIDTH CRYSTAL FILTER, DIGITAL DISPLAY, DDS FREQUENCY CONTROL AND RF AND AF GAIN CONTROLS.
STEPS AVAILABLE: 1 HZ, 10 HZ, 100 HZ, 1 KHZ, 10 KHZ AND 100 KHZ
for ease of tuning
CIRCUIT BOARDS ARE NOW AVAILABLE
SINGLE BOARD HF RECEIVER
IN A SIMPLE HOME MADE CABINET
SEE NEW FILES AND PICTURES ADDED AND FILES TO MAKE 3D PRINTED ENCLOSURE DESIGNED BY KK6US
Note:
Although built here for the 40 meter band, Changed values in the bandpass filter section allows operation on 160 to 10 Meter HF bands as well. Software covers all HF bands as written. USB not supported on bands below 40 meters. LSB not supported above 40 meters.
NEW SOFTWARE IS AVAILABLE NOW TO ALLOW USE ON USB FOR RECEIVING DIGITAL MODES ON 40 METERS. CW ALSO STILL SUPPORTED. NO HARDWARE MODIFICATIONS ARE REQUIRED.
Also now available in download section, is a circuit for adding AGC function and S-meter to the receiver.
Click the Blue Button on left to purchase a Printed Circuit Board for this project
Non-USA address please add $16 postage.
Click the Blue Button Above to purchase a Partial Kit for this Project. The complete listing is in the Related Files and Pictures button.
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NOTE: NEW SOFTWARE IS AVAILABLE FOR DOWNLOAD TO FIX RELAYS NOT LATCHING . GO TO RELATED FILES
HIGH FREQUENCY CW AND SSB SDR TRANSMITTER
This transmitter is a more complex project and is not recommended for the beginner builder. It operates on 160 to 10 meters QRP and has great stability due to DDS control via a Texas Instruments Microprocessor
This design was in the August 2017 QST
REAR PANEL VIEW
The design consists of three main boards. One generates all frequencies necessary and based on the tune frequency selected, switches the proper filtering in line. A second board generates the SSB signal, filters it and mixes the frequencies to the transmit frequency output. A third board filters and amplifies the signal.
You can use two boards (A & B) for an analog SSB/CW transceiver if desired and supply the local oscillator and BFO frequencies from elsewhere or modify the software to add local tuning.
FRONT PANEL VIEW
Combine this transmitter with the SDR receiver shown on this page and you will have a complete SDR transceiver. Use with any computer or tablet for control and display
A SET OF THE THREE MAIN BOARDS IS AVAILABLE. $30, shipping included
Non USA address add $16
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Project from 1982-1983
This receiver/transceiver was featured in two issues of Ham Radio Magazine, July 1983 and November 1984
Here is a link to copies of the articles. This is included here for reference only. I have no boards for this and the design contains some obsolete components but several of the circuit designs are still useful today. I still use this transceiver at times The amplifier is not included in the documentation.
