I’ve recently been working on a project involving GPS, and wanted to find an inexpensive lightning arrestor. It needed to have DC pass through to power the active GPS antenna, it needed to be able to pass the roughly 1.6GHz signals without much attenuation, and I preferred it to have SMA connectors as that’s what’s on the cables I’m using.
I was able to find a few cheap options below $20 on Amazon marketed at WiFi devices, and supposedly specified to 6GHz, which is well higher than I require. For that price point I decided it was worth buying one to test and see if it would work for my application, and I’m pretty pleased with the results.
The device itself looks to be of good quality for the price. It has a machined body and all the surfaces look pretty good. Inside is the center conductor with a notch for the gas discharge tube to press against.
Mechanically this is a real simple device, and looks to have been constructed reasonably well. Though I still needed to measure the RF performance to make sure losses would be acceptable in my application.
Here you can see a pair of thru plots I captured. The first being a larger sweep from 1 to 2000MHz, and the second being a ‘zoomed-in’ sweep of 1550 to 1600MHz covering the GPS L1 frequency at roughly 1575MHz. The 0.0dBm Display Line being the reference line for no loss, and 1dB divisions. In the wider graph, we see the worst case loss being at roughly 0.5dB, and in the more specific sweep, the loss at the GPS L1 frequency looks to be about 0.3dB.
I’m quite pleased with this performance, and at this price point the device seems like a no-brainer choice to use in my projects in locations that require some additional protection.