Review: Com-Power PAP-501 broadband preamp

Kenneth Wyatt- December 14, 2012

I had a chance to visit Com-Power Com-Power (http://www.com-power.com) in Brea, California, this last October, just prior to an EMC seminar I was presenting for the IEEE EMC Society - Orange County Chapter at CKC Laboratories just next door. Com-Power makes a variety of EMC measurement tools and probes and they graciously allowed me to review their broadband preamp.



Figure 1 - The Com-Power PAP-501 broadband preamp.

The approximately two-inch square preamp is powered from an external 6V wall-wart power supply with standard barrel-type power connector and I suspect you could connect up a set of four AA cells to power it remotely. There is a green LED power indicator on the bottom edge, which would be a valuable reminder when running on battery power.



Figure 2 - The preamp under test using the tracking generator feature of the Rigol DSA-815TG spectrum analyzer.

It's advertised to amplify from 10 to 1000 MHz at about 21 dB of gain, so I threw it on my Rigol DSA815TG to check that out. The measured gain is 20 to 22 dB and extends all the way to 1.5 GHz - the limit of my analyzer.



Figure 3 - The measured gain from 1 MHz to 1.5 GHz.

The maximum power input is just +10 dBm (despite the 0 dBm indicated on their web site), so is fairly robust.

I found the preamp ideal for boosting the signals from my Beehive or Com-Power near-field probes, as well as the output from the FCC F-33-1 current probe. This would be an ideal accessory for troubleshooting radiated emission problems on products.

The unit is sold through a variety of distributors and is priced at a reasonable $475. Check Com-Power's web site for ordering information.