Description: Item Description: For sale today is one 10MHz GPS disciplined OCXO board with Square Wave, Sine Wave, and 1PPS outputs. This board has a new NEO-M9N GPS module (from Mouser) and a used 12V CTI OCXO. Stability is about +/-2E-10Hz at 10MHz with occasional excursions to +/-3E-10Hz. As the OCXO is operated over time, the output stability should improve. If GPS lock is lost, the OCXO output will track the reference oscillator on the GPS module for the duration of the outage. With a good outside antenna, loss of lock should be rare. Beware GPSDO listings without a frequency difference plot or with a plot that is averaged. If they show a frequency counter display look for min and max frequency and details about the reference used with the counter. Look for a spectrum plot at a minimum for units offering a sine wave output. The board has a CMOS square wave and filtered/buffered sine wave output. The sine wave output from this board is transformer isolated and conditioned by a 4th order bandpass filter. The output is adjustable to about 6dBm. The spectrum plot is with a 10dB attenuator at the input. Harmonics and spurious signals are more than 60dB below the output. The 1PPS output is CMOS and is a 400uS high level pulse every second, derived from the OCXO. There is depopulated circuitry on the board, it is not necessary for operation. This board does not have Time Nuts stability or accuracy but is more than adequate for general use.... It will be far better than any GPS module only type of reference and is close to the BODNAR (see last picture) which is a GPS receiver conditioned by an SI5328C jitter reduction chip. Unfortunately I did not have access to the BODNAR unit long enough to get a longer plot. See my other listing for a four channel Distribution Amplifier board that can work with this board. Contact me for custom versions of the board. Condition: This is a hand assembled board with a UBLOX NEO-M9N GPS receiver conditioning a used CTI 10MHz OCXO with an analog PLL. The 10MHz outputs are SMA connectors. The 1PPS output uses a two pin HIROSE DF3-2P-2DS connector (not installed in the picture). The connector will be on the board and come with the mating connector with 12" wire attached. Power required is 12VDC at under 300mA during warm up and about 170mA once the OCXO is at temperature. Power is via a two pin terminal block. The mating connector with wire pigtails will be supplied with the board. The OCXO on the board will be at temperature in under 15 minutes and the GPS should be locked well before that. There is an LED on board to indicate GPS lock. The PLL has a long time constant, it could take over an hour to get to the stability shown on the frequency difference plot. As seen on the plot, the output improves with time. This board is configured for a 5V active GPS antenna with power through the coax like those listed on EBAY here: https://www.ebay.com/itm/254926305535. The board can also be configured for 3.3V by moving a resistor. When using a GPS receiver for timing it is best to use a fixed mount outdoor active antenna with a good exposure to as much of the sky as possible. If limited, try to get south, east, and west. The board can be also be used with a passive antenna or with an active puck style antenna but results may be different than listed. The UBLOX GPS user interface is available via an on board USB connector if the user wants to monitor satellite reception. UBLOX software (not included) is required for this. There is no need to access the USB during normal operation. The board is approximately 2.9" by 3.9". The board will fit in a Hammond Engineering 1455N1201 enclosure available at Mouser or Digi Key. The 1455N1201 has metal end plates, the 1455N1202 has plastic end plates. PayPal Confirmed Address: PayPal address must be confirmed and must be the same as the shipping address.Returns: All items are sold as-is unless otherwise stated. Returns: Returns accepted within 30 days. Feedback: Feedback is important to me, please email or contact me with any concerns, issues or problems before leaving feedback and give me the opportunity to work things out if needed. I always leave positive feedback after receiving feedback from the buyer, that way I know the buyer is happy and the transaction is complete. Shipping: Shipping is to USA only as this board is not RoHS compliant at this time.
Price: 149 USD
Location: New Hartford, Connecticut
End Time: 2024-11-28T21:29:56.000Z
Shipping Cost: N/A USD
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Item Specifics
Return shipping will be paid by: Buyer
All returns accepted: Returns Accepted
Item must be returned within: 30 Days
Refund will be given as: Money Back
Brand: N/A
Model: N/A
Product: GPSDO
