TACGPS backup module

sorry, still under construction ... see current status

Schematics & Layout

The schematics design was made with ORCAD IV and the PCB layout with TANGO PCB / ROUTE.

schematics page 1 (gif, ps): root page: power supply + RS232 + 1PPS drivers
schematics page 2 (gif, ps): 50 MHz VCXO controller (*)
schematics page 3 (gif, ps): 4-channel NIM output driver
layout silk print layer (gif, ps)
layout top layer (ps only)
layout bottom layer (ps only)

Miscellaneous

bill of materials for the board (ICs, resistors, etc.)
CAM files (zipped) as filed to Advanced Circuits on 28 August 1998 for etching service.
The VCXO controller circuit (*) design is based on the article "A GPS-Based Frequency Standard" by Brooks Shera published in the July 1998 issue of QST magazine.

Piggy-back module: Motorola VP/UT+ Oncore GPS receiver

This picture shows the "Totally Accurate Clock" (TAC-2) evaluation kit with a Motorola VP Oncore GPS receiver mounted underneath.

Technical notes for the Motorola Oncore module:

CNS Systems: CNS Clock and TAC32 Installation and Operation Manual.
Motorola Oncore GPS User's Guide (password needed, for K2K/SuperK collaboration members only):

Quick Start (2 pages, 103K pdf)
Chapter 3: Receiver Description (45 pages, 320K pdf)
Chapter 4: Antenna Description (32 pages, 864K pdf)
Chapter 5: Remote GPS Engineering Notes (15 pages, 477K pdf)
Chapter 6: I/O Commands (95 pages, 224K pdf)
Chapter 7: Evaluation Kit (37 pages, 176K pdf)
Appendix (18 pages, 63K pdf)
Motorola Oncore Technical Application Notes:
UT Plus Oncore (1 page, 31K pdf)
100PPS Feature on UT Plus Oncore (1 page, 30K pdf)
Auto Survey Feature on UT Plus Oncore (1 page, 28K pdf)
Recommended Usage of UT Plus Oncore and VP Oncore Commands For Timing Applications (4 pages, 45K pdf)
Rollovers in 1999 and 2000 (1 page, 28K pdf)
Time RAIM Algorithm (2 pages, 32K pdf)
Time RAIM Simulation (2 pages, 32K pdf)
UT Oncore Firmware Version History (2 pages, 24K pdf)

Version 2.2 (2 pages, 24K pdf)
Version 3.0 (1 page, 19K pdf)
Version 3.1 (1 page, 19K pdf)

Motorola Products: Year 2000 Readiness Status (1 page, 15K pdf)
Synergy Systems Tech Notes:
#310: OEM Net Prices for Oncore^TM Receivers (1 page, 8K pdf)
#489: XTS/II GPS Sensor Engineering Evaluation Kits (1 page, 6K pdf)
#490-1: Motorola Oncore^TM Product Summary (2 pages, 20K pdf)
#501: Motorola Oncore GPS I/O Software Commands (2 pages, 37K pdf)
#852: VIC-100 Timing Antenna (1 page, 330K pdf)
TEST RESULTS AND ANALYSIS OF A LOW COST CORE GPS RECEIVER FOR TIME TRANSFER APPLICATIONS, presented by the Motorola Position and Navigation System Business group at the 1997 IEEE Frequency Control Symposium, Orlando, FL (9 pages, 89K pdf)