TrueTime Symmetricom XL-DC OCXO GPS 10Mhz GPSDO Oscillator LCD Clock ** PARTS ** [For Parts]

** FOR PARTS OR REPAIR *** • Upgraded OCXO Oscillator • Large Left LCD Time Display • 5V Antenna Power • GPS Disciplined 10MHz Oscillator • Atomic Clock Timecode Receiver • 10Mhz 5Mhz 1MHz Frequency Outputs • IRIG-B / 1PPS • 115V or 230V Power

Description

Here's a used TrueTime/Symmetricom XL-DC GPS time receiver/timecode generator in good cosmetic condition. It is equipped with an upgraded OCXO oscillator. It is being offered for PARTS or REPAIR, as a FINAL SALE NO RETURNS transaction as it partially works. It has been tested for acquisition of GPS Time Sync and for good GPS Time, Date, Timecode and Frequency outputs on the rear panel. Note that the unit syncs to GPS time and not UTC. There is currently an 18 second difference between the two. Normally these default to UTC time and can be set to GPS time as an option. This unit seems to be factory set to GPS time and I could not find a way of changing that.

This unit has an intermittent problem with the LCD displays and the front panel. Sometimes the displays are garbled and the front panel buttons are inoperative. It seems that once the unit has run for a while the displays and buttons then function normally (as shown in the images). I don't know the cause of this, but it does suggest to me that the LCD modules are good and potentially suitable for a transplant to a different board if required. Maybe a capacitor on the front panel PCB is reaching end of life.

Aside from the time being 18 seconds ahead of UTC, the GPS Disciplined 1PPS,10, 5 and 1 MHz outputs should be accurate, as well as the IRIG-B timecode. Also, I was unable to send and receive data using the DB9 serial port using my test PC's Hyperterminal application. I don't know if this is a fault, a feature that wasn't ordered by the customer, or a configuration issue. In any case, all the important parameters for the device are accessible via the front panel keypad, so the serial I/O is probably unnecessary for most applications. I have not explored the 86-729-15 and 86-383-5 expansion cards for lack of documentation, but I do see some config options coming up on the front panel so I assume they are working as they should, but this is not guaranteed. The internal Lithium memory back-up battery has just been replaced so that should not need further attention for some years. Both LCD displays have a backlight; both are bright and even - see photos which show the actual item for sale.

A basic test antenna is included to get you started - so you may need to take both receiver and antenna into the open air to test the device. The Antenna voltage is 5V so almost any good quality GPS antenna should work, but try and have at least 26dB of antenna gain if you want to replicate my test results. A Symmetricom AT575 type is recommended and I usually have some listed separately. Rack ears are included as shown. No printed manual is included but a copy may be downloaded from https://www.prostudioconnection.net/1112/xl-dc-manual.pdf. No unpictured cables, accessories or documents are included.

I'm sharing the results of my testing to help you in your purchase decision, but I do not guarantee that you will get the same results or reach the same conclusions. Nor that I haven't missed some important point. Please bear this in mind in your valuation.

Features (Conformance NOT Guaranteed)

• Less Than 40 Nanoseconds rms Accuracy to GPS Time
• Better Than 1x10-12 Frequency Accuracy
• Versatile and Modular Architecture
• Supports Many Different Output Options
• 10Mhz, 5Mhz and 1MHz Sine Wave Outputs
• 1 PPS Output
• IRIG B Time Code Output