HP0811 Bias Board
This is a project for a bias board for an HP10811 family OCXO. Some of these models, particularly the HP10811D, as well as perhaps others such as the HP10554A may work with no changes. Other HP OCXOs such as were used in some test equipment may not plug directly but may be wired to the edge connector pin connections and also obtain both oven and oscillator support. In addition to providing these voltages when operated from an 11-16 VDC supply, this board can use EFC tuning voltage supplied on one of its outputs so that only the 12VDC source and a single coaxial cable need be used to interface the OCXO. This is particularly intended for use with newer REference board designs, starting with v3, so that one of these high quality OCXOs may be used in a GNSS aided FLL from that reference or in the case of very high quality OCXOs such as the HP ones, even used for long periods of time without the need for GNSS satellite antenna and disciplining at all. In this latter case, once an OCXO has been stabalized over a period of time so that the tuning can be learned, longterm performance may be so good that it only need be re-learned very infrequently to be within parts-per-billion accuracy. This will hold while the excellent close-to-carrier phase noise performance of these OCXOs may be used to advantage.
KiCad Files for this project may be downloaded, unzipped and the fabrication files in the 'Production' directory dropped onto the JLCPCB web site for PCB fabrication and assembly.
If used with one of the HP OCXOs having a PCB edge connector interface, that connector will need to be supplied separately. If used with some other OCXO wiring from the connector pins may be added to that OCXO.
The 10811 or 10544 plugs into the connector on the PCB. The PCB sits on four rubber feet with 11-15 VDC input and RF&Tuning, RF SMA outputs. At 13 VDC startup current is about 1A while the oven is heating and the red LED lights. Once oven regulation is reached the green LED lights and current drops to around 200 mA.
Donations Accepted, see HW home page