Monday, 27 November 2017

LATEST Sketches and Libraries

Here is the latest update of my sketches and libraries.


Previous sketches have output HIGH/LOW signals on a one connection on the 4-way jack on the VFO hardware. This signal was coded from D12 to switch the first PA I made from RX (HIGH) to TX (LOW).
The new sketches output active LOW codes on two pins of the 4-way jack, with Arduino UNO connections body=GND, ring=D12, ring=D13, tip=+5V.

These connections were chosen to also support a GPS receiver connection to the box.

For the PA-2 switching D12 is used as the LSB and D13 as the MSB of a two bit binary code. This code is then used as,


HL = TX 40m LPF

LH = TX 30m LPF

LL = TX 20m LPF

The codes are used to switch the three LPFs in the PA-2. And also to switch the Antenna connection from RX to TX.

Sunday, 19 November 2017

Slow build QRP PA-2

I've been at this project for a while. But its slowly coming together. It is a QRP PA (2-3W output) for 40, 30 & 20m. It uses a MMIC pre-built module running on 12-15V, a set of three LPFs and an Arduino Nanocomputer to run things.

It provides TX RX switching and LPF switching from a two bit binary input on the rings of a a 4-way jack (the other connections are body GND & tip +5V. This input is compatible with my VFO output jack- this jack is used for GPS inputs when finding time and Maidenhead Locator, and as a TXRX/band command to the PA running other sketches which generate WSPR, JT65, CW, PSK, RTTY signals.

IMG 1694


The display is simple, just the title "PA, the band big in the middle and TX or RX at the bottom.

Tuesday, 7 November 2017


I just noticed that Elektor has cut it's prices in a sale! The Elektor SDR broad band receiver can now be bought for €30!!! This will tune from 100kHz to over 50MHz using an Si5351 DDS. programmed from an Arduino.

Put this together with an Arduino UNO at around €9, a small OLED display and a rotary encoder for around another €9, and you can build a very decent SDR for less then €50!!!

Check it out.

Screen Shot 2017 11 07 at 11 47 26

I built one, which I use with a low cost 96kHz ADC and HDSDR running on either on my MacBook or a PC.

Screen Shot 2017 11 07 at 11 52 08

Screen Shot 2017 11 07 at 11 56 30

I have put the software on this blog, look for my latest download of my sketches.

Friday, 3 November 2017

Quicky on new FT8 mode

Some slides I have presented to BARS Tech Group

FT 8 001FT 8 002FT 8 004FT 8 005FT 8 006FT 8 007