After reworking the GPS receiver I was pretty much ready to go.
Firstly many thanks to Dan Trugian (M0TGN) for his advice regarding the GPS board. I’ve used the 10uF and 1uF decoupling capacitor set up as per the datasheet. Dan advises that a simple 10nF ceramic capacitor across ground and Vcc does the job. Also, ensuring that the screen on the cable between the beacon and the GPS is connected to respective ground terminals on each is a good move. Cheers Dan for the help, much appreciated.
Dan maintains his own site which is well worth a visit http://www.m0tgn.com/
So with everything plumbed in on power up everything was looking good.
The menu system took a while to work through but is simple enough.
My current settings are below for reference
Hitting run, resulted in an instant accurate clock and a pulsing heart icon, indicating that the GPS had achieved satellite lock and was sending data to the beacon.
The next nail biting 10 minutes were spent crouched over the tiny display watching in anticipation.
The >40 indicates the next transmission will occur at 40 mins past the hour, so just over 8 minutes to go.
And it’s off!! The 8, 16, 46 increment shows how far through the transmission the beacon is. A WSPR transmission is 160 characters long and comprises 3 tones, indicated by the last digit on the bottom right.
At the end of the transmission the beacon runs through it’s calibration cycle using GPS data and makes adjustments to the frequency and saves them to the on board EEPROM.
It then drops back into it’s waiting state ready to transmit at the next pre-defined time slot.
2E0DFU - playing with amateur radio 