Bitx20 Version 3 Manual Pdf
MKARS80 Transceiver kit | |||||||||||||||||||
The MAKRS80 is a QRP transceiver designed for use for use on the 80M band, the circuit was developed from the BITX20 designed by Ashhar Farhan. Although simple in design perceived performance is as good as a commercial transceiver. Main changes from Ashhar's original design are the inclusion of a frequency counter and a Huff and Puff frequency stabiliser; this circuit will help keep the VFO tuned to the same frequency for long periods without any 'drift'. As seen in the photo to the left, all components are mounted on to a single high quality PCB making construction relatively straight forward. The only 'wiring' needed is short pieces of wire to connect the potentiometers to the PCB. To assist with construction there is a comprehensive manual that can be downloaded from this page, also available for download are a drilling template and front panel overlay. Why not joint the MKARS80 support group? | |||||||||||||||||||
| |||||||||||||||||||
Photo showing a typical finished MKARS80, note that the knobs supplied as an option are all black without the aluminium inserts. | |||||||||||||||||||
Downloads MKARS80 construction manual version 1.4 Latest version for currently supplied kits. MKARS80 construction manual version 1.3 in Spanish Thanks to Jon EA2SN for the translation Drilling template Printout with Adobe Acrobat reader, set paper size set to A4 and page scaling set to 'none'. Stick onto case as described in construction manual and use as a drilling template for the holes and cutout. Panel overlay (Use for undrilled box only) Print and laminate as a front panel, alternatively use the mirrored overlay below. Mirrored overlay (Use for undrilled box only) Print on acetate and use as a front panel, the print will then be on the reverse side so it doesn't become scratched Panel overlay for use with ready drilled box Print and laminate as a front panel. Hires Schematic (JPEG) Bold Text Schematic (PDF) Two different formats of schematic which will be easier to read than that in the manual | MKARS80 PIC firmware Download and modify for your own use, perhaps the easiest modification is to change the startup screen to include your own callsign. This will require the installation of MPLAB, download from the Microchip website free of charge. VFO stability modification Makes a significant improvement to the VFO stability on early transceivers, this was incorporated into the kit from Dec 2008 Old data MKARS80 construction manual V1.0 Only for use with kit version V1.0, this has minor component differences so don't use with other versions MKARS80 construction manual V1.2 For kit version V1.1 and V1.2 MKARS80 construction manual version 1.3 For kits supplied prior to 20-03-2016 NOTE: Kit version can be found on component listing in all component bags. | ||||||||||||||||||
Kit Contents The kit contains all PCB mounted components including display, connectors and a ready programmed micro. The builder will need to provide a loudspeaker (3-32 Ohms) and an electret microphone; a dynamic type can be used if the bias resistor (R17) is removed or a series capacitor is installed between microphone and transceiver. Knobs are supplied with the boxed kit as standard, they may be ordered as an option for the kit sold without a box. Neither kit comes with an overlay, you can either design a personal version or print off one of the options above. | |||||||||||||||||||
Availability Unfortunately some key parts (10MHz crystals, variable capacitor) have become obsolete, I have a small stock of variable capacitors and in order to use these up and produce a small batch of kits I'm trying to find a source of crystals, until I can do this the MKARS80 will be unavailable. Steve G6ALU |
BITX20 by Hendricks Kits. This little board should have been a ‘work first time’ toobut it isn’t. The BITX20 was originally designed by Ashar Farhan VU3ICQ, and the aim was to use common, low cost parts. This would mean that radio amateurs in poorer countries could build a working SSB transceiver and work the world on 20m.
Assembly, Testing, and Operating manual. Stepbystep assembly will be in a format that looks like this: 1. Solder and inspect connections This layout provides checkboxes for marking each completed step during assembly. Procedures will be. The Bitx Version 3 PCB is for $10 PCB +Coils+1 No 2570 transistor. The Avala sdr pcb is for $5.Shipping is extra $ 10. I looked at this web page to get an idea what the Avala sdr was and decided that I couldn't pass up a deal like this. After a trip to paypal, the boards for the bitx and the avala were ordered. Soon I received a package in the.
The BITX Story
Farhan VU2ESE designed and published the first BITX transceiver. His web page documents that work:
![Online Online](/uploads/1/1/9/5/119561264/364961750.jpg)
Shortly after that event, the BITX discussion group on Yahoo Groups was started by Farhan VU2ESE and Hans G0UPL:
Hans G0UPL put together the first parts kits for building your own BITX20. Since that time there have been many BITX transceivers built using 'ugly construction' method, and several now offer kit versions for 20 meters, and other bands:
QRPKITS.COM BITX20A, BITX17A, BITX40A
BITX-40 Partial Kit from India (http://www.hfsigs.com/)
In addition, there have been several PCB layouts published via the discussion group, and a PCB set for Farhan's original BITX20 is available from Far Circuits
Bitx20 Version 3 Manual Online
Leonard KC0WOX has contributed immensely to the BITX knowledge base, and by providing help for those having trouble with their BITX builds. Leonard's BITX work is found on his web page at
Bitx20 Version 3 Manual Download
Coil Placement Chart for BITXxxA kits (20 March 2010).