The schematic seems to have 4 pages (only page 2 is in the PDF) and the description indicates that ICs Z19, Z14 and Z10 recover the IRIG code but the relative schematic page is missing...
On Sun, May 24, 2015 at 9:55 PM, Joseph Gwinn <[email protected]> wrote: > Responses interspersed below. Joe > > On Sun, 24 May 2015 12:00:01 -0400, [email protected] wrote: >> >> Today's Topics: >> >> 9. Re: IRIG-B audio decoder circuits and ICs sought (Esa Heikkinen) >> 13. IRIG-B decoder schematic (Tim Shoppa) >> >> >> ---------------------------------------------------------------------- >> >> >> ------------------------------ >> >> Message: 9 >> Date: Sun, 24 May 2015 10:33:47 +0300 >> From: Esa Heikkinen <[email protected]> >> To: Discussion of precise time and frequency measurement >> <[email protected]> >> Subject: Re: [time-nuts] IRIG-B audio decoder circuits and ICs sought >> Message-ID: <[email protected]> >> Content-Type: text/plain; charset=UTF-8; format=flowed >> >> Joseph Gwinn kirjoitti: >> >>> When I last used IRIG-B005, the vendor (Symmetricom?) said it was good >>> for a few meters only on shielded twisted pair. I recall that the >>> handling of shield grounds was strange. This was OK, because the >>> signal was confined to one cabinet, and it worked just fine. >>> But there was no mention that the B005 followed RS422 or RS485 or >>> anything else. Nor does IRIG 200-04 say this, so I suspect that each >>> company solves it differently. >> >> Yes, there seems to be many implementations. >> Quote from Technical Note TN-102 from Cyber Sciences: >> <http://www.cyber-sciences.com/documents/TN-102_IRIG-B.pdf> >> >> The IRIG 200-04 standard does not define specific signal levels for IRIG-B. >> Typical techniques for transmission of unmodulated IRIG-B include: >> - TTL-level signal over coaxial cable or shielded twisted-pair cable >> - Multi-point distribution using 24 Vdc for signal and control power >> - RS-485 differential signal over shielded twisted-pair cable >> - RS-232 signal over shielded cable (short distances only) >> - Optical fiber >> Typical techniques for transmission of modulated IRIG-B include: >> - Coaxial cable, terminated in 50 ohms or higher. >> - Shielded twisted-pair cable >> >> So your main concern with unmodulated version is compatibility between >> different vendors. > > Yes, now and in the future as things fail and are replaced. > > >>>> Yes, planning to buy at least one spare unit when their prices will drop >>>> on Ebay... :) >>> The problem is that they don't handle GPS week field overflow gracefuly. >> >> Yes. Internal GPS of TS2100 cannot be used anymore, it failed alrady in >> February. Used external PPS since then. Since having external PPS is >> major problem for most of the TS2100 users I hope that the price of >> these units will drop soon on Ebay. >> >> I'm interested to buy especially rubidium version of the TS2100, if >> someone has working one having only the GPS problem... > > Are you trying to synchronize a Rb unit via IRIG-B12x? Tried that > once. It doesn't work - the IRIG-B12x signal can wiggle faster that > the Rb can follow, so the Rb never syncs, or the sync is ratty and > fragile. IRIG-B005 can work though. That was the solution. > > > >> >> ------------------------------ > >> >> >> ------------------------------ >> >> Message: 13 >> Date: Sun, 24 May 2015 07:05:14 -0400 >> From: Tim Shoppa <[email protected]> >> To: Discussion of precise time and frequency measurement >> <[email protected]> >> Subject: [time-nuts] IRIG-B decoder schematic >> Message-ID: >> <caj_qrvz0e08747ryekqnunggp6x5wtw145n6bcdti6ax6pd...@mail.gmail.com> >> Content-Type: text/plain; charset=UTF-8 >> >> Truetime 820 was made in the 80's and 90's and we have many at my day job >> fed with 1kHz AM modulated IRIG-B120. >> >> Schematic at http://www.trailing-edge.com/IRIG-B-DECODER.pdf >> >> Useful if you also have the theory of operation at >> http://www.arsitec.com.br/arquivos/produtos/man-820-210.pdf >> >> Tim N3QE > > Got them; thanks. I'll sturdy them. > > > >> ------------------------------ >> >> End of time-nuts Digest, Vol 130, Issue 35 >> ****************************************** > _______________________________________________ > 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. _______________________________________________ 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.
