I don't use one on my gpsdo feed line. The shield of the feed line is grounded prior to it entering the house and I don't live in a lightning prone area. The gps antenna I use apparently has diode protection to provide some immunity to near by lightning strikes. Most of my radio antennas are dc grounded. I also had a dedicated roof top ground system installed during some prior home renovations that the coax shields of my roof top antenna(s) are connected to. This ground system is in turn connected to the electrical service ground out side of the house. I'm hopeful the roof top ground will be a more attractive path to ground for lightning than the shields of the feed lines that run into the house that are connected to gpsdo's and radios that are in turn grounded via the electrical system in the house. If I see a surge suppressor for a decent price on eBay I might re consider getting one, but I'm unsure if it would make much difference in my circumstances in the event of a direct hit. I'm primarily interested in protecting the house and it's occupants. The survival of the radios is a fairly low priority to me. I hope I never get to find out what happens if my roof top antennas get hit by lightning. Regards Mark Spencer Sent from my iPad

There's not much in this world that is able to reliably protect a radios input from a direct lightning hit (maybe a block of copper instead of the antenna...). But a surge protector (sometimes called EMP protector or surge arrester) can increase the probability that a nearby lightning strike won't induce to high a voltage surge on your receivers input. Since the input itself may have protection diodes the surge arrester has to eliminate the part of energy, that would blow the diodes. If you have a look here http://precision.hubersuhner.com/co-rub/mozilla/products/hs-p-rf/hs-rf-lightning-protectors/hs-p-rf-lp-pg/hs-p-rf-lp-pg-fp.htm you'll find types, that are able to handle up to 30kA. If you could get a GPS receiver protector for, say, 15 or 20 Dollars, I would apply it. It should be designed to particularly protect receivers, since transmitter protectors have higher ignition voltages. Cheers Volker - DF9PL Am 26.11.2012 19:18, schrieb Mark Spencer: > I don't use one on my gpsdo feed line. The shield of the feed line is grounded prior to it entering the house and I don't live in a lightning prone area. The gps antenna I use apparently has diode protection to provide some immunity to near by lightning strikes. Most of my radio antennas are dc grounded. I also had a dedicated roof top ground system installed during some prior home renovations that the coax shields of my roof top antenna(s) are connected to. This ground system is in turn connected to the electrical service ground out side of the house. I'm hopeful the roof top ground will be a more attractive path to ground for lightning than the shields of the feed lines that run into the house that are connected to gpsdo's and radios that are in turn grounded via the electrical system in the house. > > If I see a surge suppressor for a decent price on eBay I might re consider getting one, but I'm unsure if it would make much difference in my circumstances in the event of a direct hit. I'm primarily interested in protecting the house and it's occupants. The survival of the radios is a fairly low priority to me. > > I hope I never get to find out what happens if my roof top antennas get hit by lightning. > > Regards > > > Mark Spencer > > > > > > > > > Sent from my iPad > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > >