Fluke 6060B Instruction Manual page 207

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1 32-1 . INTRODUCTION
The Medium-Stability Reference, Option - 1 32, provides the Generator with a medium­ frequency
stability
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1 32-2. OPERATION
The Medium-Stability Reference is selected as as the Generator's reference when the
Generator's rear panel REF INTI EXT switch is set to INT.
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The Medium-Stability Re f erence does not have standby power nor is its oven
kept warm during external ref erence operation. There f ore, each time the
s pecifications. The warm-u p time is typically 5 to Medium-Stability Ref erence is selected , a warm-u p time is required to meet
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s pecifications f or details.)
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1 32-3. CIRCUIT DESCRIPTION
The Medium-Stability Reference printed circuit assembly (PCA A5AJ) consists of
ovened oscillator (Y l ) and an
also available under the Module Exchange Program. The ovened oscillator (Y I) is not
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field repairable and is not described here.
The PCA is mounted on the left side rail. The PCA is connected to the +5V power supply
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and to control signals via cable W25. The output is connected to the Synthesizer PCA
(A2AI) through cable W24.
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Two NAND gates of
signal. Another NAND gate of
oscillator circuit of Y I .
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When the REF INT 1 EXT switch is set to EXT for external reference operation, the
control line EXREFL is set low. This disables the oven and oscillator circuit of Y l and
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also disables the ac-to-
1 32-4. ADJUSTMENT
This procedure is used to adjust the frequency of the Medium-Stability Reference. For
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the best results, the Generator should be warmed up at room temperature before
proceeding with the adjustment
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Med i u m -Stabil ity Reference
reference.
NOTE
ac-to-TTL
converter. The PCA is field repairable and is
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are used to convert the oscillator's ac-coupled output to a
and transistor Q I control the power for the oven and
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TTL
converter to prevent it from oscillating spuriously.
procedure
(see step I , below).
Option -1 32
0 minutes. (See the
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an
TTL