Analog design and test: using older testers in new ways

Its interesting how really old digital or mixed signal testers can be used in new ways with a good loadboard. I do not know how many engineers remember the old IMS tester. Its really old but with proper care and maintenance still provides good service. Its basically a digital tester but there are options that allow it to operate as a mixed signal or analog tester. Even a digital only tester can be used as a high frequency analog/RF tester with  the proper load board. The high frequency – digital interface resides on the loadboard. The tester then is used in its standard capacity as a digital tester. The interface takes care of the RFMW/Analog interface. Interesting. Please visit our website for more articles of interest, products and services offered.

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Filter design: SAW filters for precise filtering. Some thoughts

SAW filters can be a great way to get precise filtering done at reasonable cost ( $1.0 – $2.00 for 915 Mhz, 26 Mhz B.W. filter). However, they do need to be handled with respect as they are ESD sensitive devices. A good app note can be found at for interested parties. Check out our website for more info and our services.

SPG designs, develops and delivers custom analog and RF/wireless asics and modules.

Comparison of the characterisitic impedance of PCB lines using the SPG calculator, TXLINE and APPCAD calculators.

A comparison was done for results obtained using the Signal Processing Group Inc., characterisitic impedance calculator, the NI TXLINE calculator and the APPCAD calculator. The results are: SPG calculator -> 71.4 Ohms, TXLINE->79.47 Ohms and APPCAD -> 68.96. Please visit our website for more information about us and more technical articles.