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I’m now after more flexibility than the experimenter boards can deliver and for 6 and 3cm projects I need to start making my own boards. The two stage MMIC gain block shown here uses NLB-310 devices and is etched on Rogers RO-4003 laminate, delivering in excess of 16dB of gain at 10.3Ghz. I’m pleased with the results, nothing fancy just using 50ohm microstrip throughout and some de-coupling of DC feeds with 1/4wave sections and open circuit stubs.
I used Press N Peel transfer material as PCB etch resist quite successfully after reading an article by Jim Kocsis WA9PYH in QEX Sep/Oct 2008. It did take some experimenting to get the process right, but I can say the results are adequate for boards at 10Ghz. There are a couple of points I’d make about this process, firstly the temperature applied to the transfer is quite critical and relying on the settings of our household iron wasn’t good enough. I used a temperature meter with type K thermocouple to get the iron setting right. It’s also very important to ensure a good transfer from your laser printer to the blue sheet, I suggest playing around with printer settings to get this right. The Press N Peel needs a good density print. Next follow Jim’s directions but experiment with the length of time you apply heat to the material, this may take a few “dummy” boards to get right.
In letters to the editor of QEX Jan/Feb 2009, Alex Mendelsohn AI2Q has some suggestions around Press N Peel circuit boards which may be well worth considering.
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