Shawn-- Welcome to the family. I'll focus on antennas, care, and feeding.
Thunderbolts tend to be somewhat deaf, and need higher gain antennas (around 35 dB) than more modern GPS receivers. They also like a clear view of the sky, particularly to the Equator. Hams will tell you that a low-loss feedline at operating frequency is very important. That can be a quality RG6 (75 ohm line), or a 50 Ohm line such as 9913 or Times Microwave LM400. The shorter the antenna run the better, but a good view of the sky is paramount. My GPS antenna shares a mast with my Davis weather station on top of our 2 story house; the cable run is LM400 down to the ham shack. I like the Symmetricom 58532A antenna, available on the usual auction place. I got mine from an HK or Chinese seller. The power supply should be low noise and stable. The Thunderbolt wants to live in a place with a fairly stable temperature. As you advance in stages of time nuttiness first you worry about clean power, then clean uninterruptable power, and then you start worrying about active temperature control. The active temperature control means you have a windows box running Lady Heather 24x7. If you're really a time nut, then you'll want to get a Symmetricom GPS antenna splitter and at least two Thunderbolts; one to run as your stable reference, and the other to work on. Sanity is highly overrated. You want to pick up a copy of Lady Heather from John's website, here: http://www.ke5fx.com/heather/beta.exe You can do this well in advance of actually having your own Thunderbolt, antenna, and all the fixins'... Assuming you have a windows box to run it on, one of the really great things about the software is that it comes with a desktop shortcut that will start it up connected to one of John's Thunderbolts, so you can "see" one in action and get an idea for what a Thunderbolt looks like when its running. You should of course peruse the archives, looking for clues on Thunderbolts and supporting Symmetricom bits. One of the denizens of the list may still have one of the antenna splitters. Who knows, might be able to find someone to cough up a Thunderbolt as well (for a reasonable price). Advice and opinions, of course, are free and worth every penny... Question away! bob k6rtm in drizzly silicon valley ------------------------------ Message: 7 Date: Tue, 15 Mar 2011 20:14:20 -0700 From: Shawn Tayler <[email protected]> To: Time-Nuts <[email protected]> Subject: [time-nuts] Thunderbolt setup Message-ID: <[email protected]> Content-Type: text/plain; charset=us-ascii We After some consideration and the acquisition of a 5370 and a couple MRT Rb sources I've decided that I should get serious and get a Time-Nuts starter reference. So what help can the group offer on navigating the Thunderbolt offerings out there? Any pit falls to watch for ? All comments are appreciated! Sent from my iPhone ------------------------------ _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
