Hi If you want to dig into something like this to learn and to maybe fiddle with a downconverter design - sure, that’s a great thing to do. It’s a hobby and (hopefully) you are set up to handle the task. You probably are already a member of a list (or three) where you have access to info on your project.
Since we have zero info about the original requester, I am indeed guessing here. That can often be a bad thing to do. My *guess* is that this is somebody who simply wants a working device. If so, there are a lot of bumps in the road that they need to understand. If the answer is “I want a simple NTP server that is setup and forget”, this is probably not the way to go. Bob > On May 1, 2015, at 9:55 PM, paul swed <paulsw...@gmail.com> wrote: > > Bob brings up all the additional details that are the reality of dealing > with teh older gear. Especially the date offsets because of the 1024 week > cycle. That is a real pain. > But the reason to spend time on something like this is to understand > something and to learn. > I picked up the austron 2000 gps because it was a useful rack mount box. > Then realized some of its unique qualities. That was the driver for > reviving it. > I was lucky that I was able to obtain some operational data and then later > schematics. BUT it was still a heck of a reverse engineering and adapting > process. > I am pretty sure I shared that on time-nuts and will guess that must be 5 > years ago now. > Regards > Paul > WB8TSL > > On Thu, Apr 30, 2015 at 5:58 PM, Bob Camp <kb...@n1k.org> wrote: > >> Hi >> >> I guess the first question would be: >> >> Are we sure it’s an AL-AK and not an XL-AK? >> >> Past that it becomes a fairly involved process of, is it worth real money >> to get this up and running? >> >> If we are talking about a $20 eBay find that is worth another $5 to have >> somebody else get it running, the >> conversation is a real short one. >> >> If the AL-AK has some inherent value (it’s a working GPS disciplined Cs >> maybe) then putting a few hundred >> dollars into checking it out and getting it running might make sense. If >> it’s like most of the parts from that >> era, the delta between getting it checked and getting it running is pretty >> small. >> >> Once you *do* have it running, what do you have? >> >> 1) Leap second problems >> 2) GPS year rollover problems >> 3) Tracking issues >> 4) A noisy receiver with very few correlators >> 5) Software support issues >> >> This is an unusual box that is at least 20 years old. It *will* have at >> least some of the listed issues and >> may have all of them. Fixing them will be impossible. >> >> ======== >> >> Why bring up all of the negatives? I for one have been sucked into this >> kind of thing a *lot* of times >> in the past. Just a few more this or that and it’ll be running fine. Much >> better to figure out the likely >> cost and outcome first. That’s *very* hard to do, and even harder to >> follow through on. If you can’t >> do the work yourself, the cost isn’t just lost time. This can cost real >> cash. >> >> Bob >> >> >>> On Apr 30, 2015, at 12:50 PM, Tom Van Baak <t...@leapsecond.com> wrote: >>> >>> I received this email. Anyone have a good answer? >>> Thanks, >>> /tvb >>> >>> ---------- >>> Someone on ebay advised me to contact your website in hopes that someone >> in your organization can help me with my TrueTime model AL-AK GPS Receiver. >> I need to send it to someone so that they can check it to see if it works >> and can track Satellites. This receiver has the onboard up/down convertor >> board that changes the receiver input frequency which is set at 4.092 MHz. >> I don't have the needed down converter at the antenna. I bought this >> receiver on ebay from someone who told me that he doesn't have the down >> converter as well and can't figure out how to get it to work at 1575.42 >> MHz. He also didn't know if this receiver can be setup for a 1575.42 MHz by >> removing the onboard converter and changing some DIP switches. If one of >> your members can at least check out the receiver at 4.092 MHz for satellite >> tracking That would be a big help ... >>> ---------- >>> >>> _______________________________________________ >>> 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. >> >> _______________________________________________ >> 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. >> > _______________________________________________ > 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. _______________________________________________ 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.