Pumpkin UM-20, User Manual

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User Manual
4 UM-20 Low-cost Oven-controlled Crystal Oscillator (OCXO) Assembly
Figure 1: GPS time and frequency reference receiver ..................................................................... 6
Figure 2: XL Microwave Model 3120 frequency counter ............................................................... 7
Figure 3: IsoTemp OCXO36-44, the "original" Option 115 OCXO for Model 3xxx frequency
counters ........................................................................................................................ 8
Figure 4: Top view of assembled module...................................................................................... 14
Figure 5: Bottom view of assembled module ................................................................................ 14
Figure 6: OCXO PCB assembly installed in Model 3xxx ............................................................. 16
Figure 7: OCXO PCB assembly installed in DS345...................................................................... 18
Figure 8: OCXO36-44 waveform (blue) compared to Z3805A GPS-disciplined waveform
(yellow) ...................................................................................................................... 21
Figure 9: OCXO131-40 waveform (blue) compared to Z3805A GPS-disciplined waveform
(yellow) ...................................................................................................................... 22
Table 1: MTI OCXO-based oscillator module from SN '142.......................................................... 9
Table 2: MTA100 connector pinout to mate to XL Microwave 3xxx ........................................... 10
Table 3: Frequency survey of OCXO131-40 units, installed on 705-01667A PCBs .................... 14
Table 4: Applications of Rev A OCXO Modules .......................................................................... 15
Table 5: OCXO131-40 frequency tuning range as a function of
R6
&
R8
..................................... 17
Table 6: OCXO module pinout to mate to SRS DS345................................................................. 19