I have installed the Efracom LPRO-101 into a used rack cabinet after removing the card cage. The cabinet had a power supply module outputting 32 vdc which will be reduced to 24 volts by a LM317 regulator to run the Rubidium. I decided to acquire a OCXO for providing the station 10-MHz Reference instead of using the Rubidium. I did this for two reasons: The Rubidium has a finite life and does not exhibit low phase noise. The OCXO was purchased from e-bay for $39.95. It feeds a Downeast Microwave 10-4 10-MHz 4-way distribution amplifier to feed equipment in the shack requiring an accurate reference frequency. A 12-volt sealed-acid battery is float charged to 14 volts to ensure the OCXO will run continuously even in event of a ac power outage. The OCXO can be periodically adjusted to match the Rubidium standard. The rubidium is mounted to a 1/4-inch aluminum plate with six counter-sunk 4-40 screws and the plate is attached to a 6-inch square heat sink with 2-inch deep fins (click image for larger view):
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Photo of a simple BITE lock indicator board made by Chuck, WA3IAC; Schematic diagram of the Rb and OCXO unit.
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Specifications:
Rubidium: Efracom LPRO
Freq. accuracy = E-11
Freq. = 6.834687500 GHz
Phase noise = -86 dBc/Hz, -118 dBc/Hz (100-Hz), -119 dBc/Hz (1KHz)
Lock time = 3-4 min.
Load = 1.7 A (start), 500 mA (steady-state), 24v
Output = 10-MHz, 7.8 dBm
OCXO: Morion MV62
Freq. Stability = 5 x E-12 short-term, 5 x E-5 annual
Warm up = 5 x E-8 >5min.
Freq. Adj. = +/-3 E-7 (6-Hz)
Var. Freq. bias = 0 to +5v (thru 20K)
Phase noise = -97 dBc/Hz, -145 dBc/Hz (100-Hz), -150 dBc/Hz (1KHz)
Load = 500 mA (start), 180 mA (steady-state), 12v
output = 10-MHz, 10 dBm
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