3 Ghz counter and power detector build Part IV Putting the counter into service

After I had soldered the remaining parts like missing passives the lcd display and user buttons the build process was finished.
Before applying power I measured the resistance of the power lines  and some other important points to ensure there are no nasty shorts hiding somewhere.

The big moment applying power.
Nothing except a short blink of the lcd back light happened .
Hmmm
Soon I figured out there is a very nice software power switch  implemented.
You need to press the ok button to switch the unit on.
Very nice, I will implement that logic in my own designs too.
Power switches are so outdated.

So the unit works. As a first test I measured the power and frequency of an fm test generator.
Without calibration the frequency part worked ok but the power measurement was of by 3 db.
To calibrate the unit I need access to the university test lab, which I don't have until September.

First impressions, pros and cons of the unit:

Pros:
Very nice power on design
Usage of qfn components I lover to solder fine pitched smd devices
Cpld design
Open source software for the microchip and the cpld

Cons:
A usb port to export data is missing
The displayed frequency is always drifting
No gate time setting
Silk screen of pcb is horrible , very fuzzy and partly unreadable (the manufacturer promised to take care of this problem though)

In the end I am unfortunately disappointed of the unit.
On the other hand it still will be a help in the spectrum analyzer build process.
I am also thinking about implementing an serial output.
To log the data in a computer could be a big help. You could for example plot the frequency versus power output of a device and visualize the stability of the power in a given range.

Finally the counter in action (Please excuse the flare on the lcd)

Links:
3 Ghz counter and power detector build Part I
3 Ghz counter and power detector build Part II
3 Ghz counter and power detector build Part III
Elektor project page

3 Ghz counter and power detector build Part III Cpld

The counter not only has a Dsp that needs programming, there is also a Cpld.
Cplds (Complex Programmable Logical Devices ) are very interesting parts.
A Cpld gives you the possibility to create your own integrated circuit.
In a very simplified explanation I would say they are made of thousands of gate arrays and configurable wires which connect between the gates and the pins.
Programming a Cpld is more like routing a pcb than programming a microcontroller.
A common language to describe your circuit is VHDL (Verilog Hardware Definition Language).

Cplds and Fpga (Field Programmable Gate Array) are very powerfull devices.
They can process tasks massively parallel are very fast but also expensive and tricky to program.

Programming a Cpld is usually done via Jtag interface.
I downloaded the Altera programmer and used a 5$ Jtag programmer clone of the Altera Usb Blaster.

Everything worked immediately .
The last step of the counter build is to add the rest of the passive components.

Successful programming of the Cpld

Links:
3 Ghz counter and power detector build Part I
3 Ghz counter and power detector build Part II
Elektor project page
Altera Homepage