GHS15-clock
TIVi (Time Imposer for Video)
How to order
"GHS15-clock" & "TIVi"
Extra links
This page is not linked from the outside because this is a private page.
Please refrain from linking from other sites.
If you have any questions concerning this page, please write to me in
easy English by e-mail as I am weak in English.
# GHS15-clock
Circuit diagram of
the "GHS15 clock" (GIF:82kB) GHS15-clock v1.0
instruction manual (PDF:154kB)
The Specificaion of GHS15-clock
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1.Voltage of power supply: 6 V DC to 40 V DC (recommendable: 6V DC to 12V DC)
* When the GPS15H-W is adopted for its receiver, it needs 8V DC to 40V DC (recommendable: 10V DC to 12V DC)
2.Accuracy of timing sync.: within 10 micro-sec
3.Time signal output method: LED(Red) beat (flasher), 2 lines 7 segments LED, Buzzer
output, Audio line out
*The rising timing of these outputs is synchronized with UTC exactly.
4.Minute signal: LED(Green) beat (flasher), Buzzer tone and Audio line out tone
changed.
 |
Beginning message |
 |
Menu1 / top: Hour, Minute (UTC), Longitude bottom: Height of receiver antenna, Latitude UTC second are displayed at 7segments LED Accuracy of positioning: within 15 m horizontally, but with a few 10 m error vertically |
 |
Menu2 / top: Geoidal height, Number of Satellites, HDOP value bottom: Map datum, Versions info |
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Menu3 / Signature |
==== via Serial port ====
Serial communications: A serial link with the GPS receiver is supported.
Free software "Satk English version" is usable.
UTC and Geodesic information are available on demand.
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* You can get an English version of the free software called "Satk" from here.
Free software "Satk (Satellite Assisted Time Keeper)" is developed by Takashi Setoguchi, Japan. This is the initial window of "Satk".
(1) Click the "Set..." button, and the "Setup form" window should appear.This is the set up window of "Satk".
(2) Choose the "Garmin std" for the "Receiver".
(3) If you check "Yes" at "Auto Adjust", the internal timer of your PC will keep accurate time after this.
(4) Close the "setup form" window, and click the "connect" button at "Main window"An image after the GPS receiver catches the GPS satellites signals.
You can get the exact UTC and Geodesic information.
However the height information (Antenna) isn't accurate enough. Generally, GPS system is weak in the height measurement.
# TIVi (Time Imposer for Video)
Connection chart with
Telescope & GHS15-clock (GIF:16kB) An example of the image generated by TIVi
(JPEG:60kB) Circuit diagram of
the "TIVi"(GIF:449kB) TIVi v2.0 instruction
manual (PDF:538kB)  |
| Synchronizing with GHS15-clock |
The Specificaion of TIVi (Time Imposer for
Video)
=========================================================================================
TIVi is a convenient instrument to impose accurate times on external VCR images.
1. Items that can be shown on the monitor
# Year/Month/Day/Hour/Minute/Second/10millisec
* You can select the items from the following five patterns:
(1)All items (2)Hour/Minute/Second/10millisec
(3)10millisec only (4)Year/Month/Day (5)No indication
* You can change the position of the items anywhere on the monitor
2. There are three ways to synchronize the clock:
(1) Manual operation. (Switch pushing)
(2) By external TTL level electric signals, such as 1PPS (pulse per second) signals of GPS
receivers.
It is possible to choose leading or trailing edges of the electric signals.
(3) By audio time signals, such as telephone time signals, or GHS-clock line out signals.
The GHS-clock signals can provide the most stable synchronization with the
instrument.
* Threshold level at (2) and (3) : 0 to 1.0V adjustable
3. Time accuracy
# within 3sec/month (= 1PPM), Real ability: about 0.5sec/month
4. Specifications of projected image signals
# Based on NTSC standards
# External image / Internal image (= Blue back) is switched automatically
# I/O terminal : RCA connector
5. Power source
# DC 5 to 15 V (small power consumption)
* TIVi consumes small electric power, so you can drive it with only 4 dry cell batteries
The important notes.
* TIVi can be used with NTSC instruments only. It cannot be used with PAL instruments.
* There might be some cases where TIVi is not compatible with some NTSC instruments.
Use it on your own responsibility.
* TIVi can be synchronized manually or by the GPS or telephone time signals.
However I cannot guarantee its use with the time signals of other countries
than Japan because I have not tested it with any of them yet.
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# Extra links
GPS using high accurate time imposer "GHS-OSD" Simple GPS clock
for "Garmin 15H-W" A sophisticated GPS
clock, "Micon-GHS clock"
This page is written by Tsutomu Hayamizu.
If you want to contact me, send mail to haya@po2.synapse.ne.jp
Translated into English with the help of Mitsuru Soma (National Astronomical Observatory, Japan)
[Updated 2012 Jan 3]
