This settings screen controls the time functions. To enter this screen, press the F6 key.

Set SDR and DOS system time. If you enter a Y you will be prompted for the date and time.

Sets the number of days before the daily channel record file(s) are purged from the system.

Used to control the Time Adjust Interval. See below for information on this setting.

Note: This setting is automatically updated when used with a time reference (WWV, WWVB, Comm Port or GPS).

Adjusts the Add/Drop interval counter used for time correction. This number can be entered in milliseconds or in HH:MM:SS.Milliseconds format. See below for information on this setting.

Note: This setting is automatically updated when used with a time reference (WWV, WWVB, Comm Port or GPS).

Sets the number of hours UTC is forward or behind local time.

Tells SDR that the local time is in daylight savings time.

Sets how many minutes before the event trigger time an auto saved event file will begin.

Sets how many minutes will be saved after the event trigger time.

Used to compensate for the travel time of the radio waves of the WWV/WWVB time standard transmissions and the tone detectors capture time. This number is in milliseconds. The tone detectors capture time is around 20 to 25 ms. You should add 1 ms for every 300km (186 miles) between you and the transmitting station.

Used if some time reference (WWV, WWVB, Port or GPS) is connected to SDR. If set to Yes, SDR will adjust its internal time to the time reference. If set to No, SDR will only monitor the time difference but not adjust too it.

Note: This menu item is not saved in the SDR.INI file.

Used to set up a window of time where SDR will correct its time against WWV/WWVB. Set this option to -1 if you want SDR to corrected against WWV/WWVB all of the time. See the WWV Time Correction Option for more information.

Used with the Lock Start Time. Sets the length, in hours, for SDR to check its time against WWV and WWVB. This option only has active if the Lock Start Time is not set to -1. See the WWV Time Correction Option for more information.

Enables serial Comm Port 1 to be used as a time standard to another SDR system. See Using the Serial Port for Time Correction for more information.

Enables serial Comm Port 2 to be used as a time standard to another SDR system. See Using the Serial Port for Time Correction for more information.

Uses one of the serial Comm Ports as a time reference. This can be another SDR system acting as a time server or if the GPS option is used. See Using the Serial Port for Time Correction for more information.

Used with the Set Time Using Comm Port option. Fine tunes some of the parameters used for time keeping.

Tells SDR to look for the WWV or the WWVB signal on digital input port 0. This setting must be set to Yes if you are using the WWVB time reference option. See the WWV Time Correction Option for more information.

Used if you have my SDR board with the temperature stabilized oscillator option on it. It changes some of the parameters used to keep the system locked to WWV. Depending on your signal quality you may get a little better time accuracy.

When enabled, SDR will check its internal time to the DOS system time every 15 minutes. If the difference is greater than 2 second, SDR will set the DOS time to the internal SDR time. If this option is off, SDR will not set the DOS system time.

Note: SDR only uses the DOS system time once at startup. From then on, it uses its internal time based from the 1 millisecond interrupt generated on the A/D card.

Tells SDR that you are using a WWVB receiver as a time reference.

Tells SDR that you are using a GPS receiver as a time reference.

When enabled, SDR will keep a running average of the position information from the GPS receiver. When you exit SDR, it will save the running average in an ASCII file named POSITION.DAT that will be located in the SDR root directory. Each time you exit SDR a new line will be created in the file. The first number in each line is the number of points averaged, next are the averaged latitude, longitude and height in meters. Please note the the height number GPS height and not Mean Sea Level (MSL) for your area. A program called GEOID can be used to calculate MSL for the GPS height number.    

When enabled, SDR will look for the 1 Pulse per Second timing signal on the RS -232 DCD line. See the GPS Timing documentation for more information.

Sets the digital output port, at pin 18 of the 37 pin Input/Output connector, to output a 1 pulse per minute pulse instead of a 1 pulse per seconds pulse. This pulse is 800 MS long with the rising edge at the top of the minute. The pulse can be used to sync other SDR systems using the digital input port mode.

The Time Adjust Interval count is used to compensate for the timing reference crystal oscillator not being exactly 4.000 MHz. SDR uses a 1 millisecond interrupt generated by the A/D card using the onboard reference oscillator. If the oscillator is a little fast or slow the time of day will slowly drift. By adding or dropping 1 millisecond at some interval it is possible to compensate for the oscillator being off frequency. The Add/Drop number is the number of milliseconds to wait before a millisecond is added to or dropped from the time accumulator.

If you use one of the time reference options (WWV, WWVB, Comm Port or GPS), SDR will calculate the Add/Drop interval number and direction (add or drop) for you. If you can dedicate an inexpensive short-wave receiver turned to one of the WWV stations you will be able to keep your time within +-15ms or less. You will probably need to run a long wire antenna so you can receive the station clearly enough for SDR to lock on the 800 ms tone sent at the top of the minute. See the WWV Time Correction Option for more information.