A new SDR

This little toy was so attractive, I had to own one! To avoid any more comments the like of "What... ANOTHER radio??" I thought I'd sell off a few other radios on eBay and finance the purchase with the proceeds. 

The sale went well, so the kit was ordered. It sells for a fairly moderate 120 Euro and comes as two cigarette pack sized PCBs and an aluminium case.

Unlike my previous SDRs this comes with a built in sound card. The entire USB traffic is handled by an ARM-Cortex M3 CPU, the LO for the mixer is the usual SI570, it's output is divided by a CPLD chip which makes it much more flexible than any 74xx divider based design.

The kit comes as two different PCBs and a case, one carrying the bandfilters, the other the actual radio. To my regret the entire kit was done in less than half an hour as all the work just consists of soldering the connectors.

What I love:

- The thing just needs USB and the antenna, that's it. No power supply, no sound interface, no additional cabling. I LOVE it.

- It rates high in WAF (wife acceptance factor)

- If works nicely with any SDR software on either MAC or PC

- Now, this is hot: As the divider is programmable since it resides in the CPLD, it covers zero to 40 MHz without any need for jumpers. It works beautifully at LF and VLF. I can easily decode a dozen NDB navaids, the local time standard station DCF77 and plenty of other stations.

- The entire thing easily goes into a shirt pocket.

What I found not yet to be ideal:

- It is a bit sensitive to strong signals. When I feed it with signals from my PA0RDT active antenna, it easily overdrives and produces funny IM products. I hooked it up to the step attenuator and that improves the situation.

 

In general I must say, I totally love the thing!