This paper presents a practical do-it-yourself approach to an experimental framework for an E-band 71–76 GHz outdoor testbed. The proof of concept presented is a side-lobe emission test to examine signal intercept vulnerabilities, for example, for potential wireless backhaul applications at 71.937 GHz for a four-radio test network. The testbed is built entirely from commercially-available off-the-shelf devices to significantly reduce costs, is weatherproofed for outdoor deployment, and is remotely accessible over a secure VPN. The testbed includes a power over ethernet (POE) arrangement, a downconverter to 2 GHz IF, a horn antenna, a spectrum analyzer and Ubuntu headless servers. The criterion for equipment selection is described for the test radios and for each testbed device.