Frequency (Tx And Rx Accuracy); Bridge O/C - H Heuer Instruments UMDT51A User Manual

Frequency (TX and RX accuracy)

To adjust both the Transmitter and Receiver Frequency accuracy of the LT51,
press the [f3] Frequency key.
Using a short, low capacitance cable connect the TXa-b terminals to the high
impedance input of a DMM configured to measure Frequency to at least 8 digits
(0.1 Hz resolution). The RTXa-b terminals should not be connected to any loads.
Use the knob (press to move the cursor) on the LT51 to adjust the TX Frequency
constant, so that the frequency displayed on the DMM is 100,000.0 Hz.
Press the key when the reading has stabilised.
The LT51will then automatically calculate the adjustment required for the RX
frequency at 1 MHz.

Bridge O/C

To adjust the Bridge function of the LT51, press the [f4] Bridge O/C key.
The message box "Connect CAL Source..." is displayed on the LT51 LCD.
Ensure that both the TXa-b and RTXa-b terminals are not connected to any
loads, ie. they are O/C.
Press the key when the reading has stabilised.
LT51 User Manual
Adjustment procedures
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