Ultimate 2 Ultimate 3 Ultimate 3s - A Swiss Army Knife for Radio

If you have a shack you need an Ultimate 3s (U3s). No I am not on a commision, it is just I find new uses for this device all of the time. Need an RF source? Need accuracy between 100khz to 140+mhz? Need a standalone CW/Wspr/PI4/JT65/Opera/etc.? Need a GPS disciplined shack clock? Do you like experimenting? If you can answer yes to any of these questions then you probably need a U3s. You will notice it in many of the projects in my notes.

This page is just an overview. There is plenty of 'How To' on the official website and forum.

Display showing GPS Info

I first came across the Ultimate 2 online. It sounded too good to be true - especially at the price of <£30. An easy to build standalone Wspr transmitter. No computer required. The U3s superseded this and is even better. In fact it, in some ways, perfectly compliments the Red Pitaya in Wspr RX mode. I can run the two together and leave alone. The Red Pitaya will listen and update all spots on 8x bands of Wspr at once. The U3s will transmit on any of six bands at a time period of your choosing. It is very QRP so no chance of damaging your sensitive receiver so long as you run seperate antennas. And on Wspr its nominal 200mw will travel the world over if conditions are right. And that is just its Wspr use.

If, like me, you have some equipment which drifts a little - especially on VHF. It is possible to run the U3s as a frequency standard. A quick press on the right button and GPS corrected, oven stabilised RF can appear on your Wspr screen to ensure you really are within, say, the 4m Wspr window.

If, like me, you like to try different modes but you are not in range of, say, a PI4 beacon. Then you can set up your own test beacon into a dummy load and watch PI-RX decode it. In fact EI0SIX uses a U3s I believe. Recently I have succeeded in spotting it. I was confident it could be done because I had confirmed everything was working here with my own U3s dummy load beacon.

And if, like me, you are interested in how things work then the U3s is the perfect way to get into basic construction. The basic U3s is cheap and easy to build. No smd. You get one band (one LPF at least) and it is quite possible to be on the air with it quite quickly. Of course there is no multiband capability or GPS discipline, or OCXO just yet. These you have to add. And you probably will. With the exception of the OCXO (still no smd but requires quite accurate soldering) it is all straightforward and you can add to the kit as you go. There is even a case to make it all look very professional.

The basic U3s on test (The LCD with the white screws is it!)

You can also keep up to date with the very active Forum. There are plenty of people who can offer advice and other resources (photographs, mods etc.) as well as Hans himself who is always ready to help.

A fully specified U3s with internal GPS board, OCXO and a full bank of band LPF

Finally as new developments come along Hans releases updated Eeproms so the thing never goes out of date. If you are adventurous you can invest in a cheap AVR Programmer and download the updated files from the website for free and update it yourself. This is what I do, too impatient to wait.

In short a vital part of the G0MJI shack.

A stack of U3s I have built into different boxes