[time-nuts] TymServe 2100 1995 Issue - A Kludgy Fix

[Chuck Harris]

Seems to me that the obvious simple answer works this way:

Since the GPS must use an RS232 connection to communicate
its information to the other devices in the telescope, all
that need be done is to write a fairly trivial program to
run on a PIC, or Arduino, that when presented with the date,
adds 20 to the year, and then sends it on to the rest of the
system.  Everything that is not a date gets passed through
unmolested.

-Chuck Harris

Pete Stephenson wrote:
> On Tue, May 5, 2015 at 2:42 AM, Andrew Cooper <acooper at keck.hawaii.edu> wrote:
>> We also ran into the TS2100 1995 bug this weekend.  For us the consequences are
>> a bit more severe...  The telescopes will not point to the right location in the
>> sky without accurate time!
>
> Ouch. I have some friends who work at the Subaru telescope. I'll check in to see
> if they're affected.
>
>> For now we have configured a temporary fix...  We set up two units, previously
>> our primary and hot spare.  The first unit is set to use GPS, which of course
>> has the correct time but the wrong date.  The first unit is sending a 1PPS
>> signal to a second unit which is set to 1PPS input mode with a manually set date
>> and time.  We now have all of the IRIG and NTP capability we need and the
>> correct date.
>
> Out of curiosity, is there no way to "prime" the device with the current date/time
> (e.g. from a wristwatch) so it can interpret the GPS week information correctly? I
> recall that several other devices have that ability.
>
> Is there a list of other common time-nut devices that are susceptible to similar
> issues? Lots of time-nuts use surplus equipment that's no longer supported and
> it'd not be fun to have them stop working.
>
> Cheers! -Pete
>