ETS-Lindgren HI-1710A Microwave Oven Survey Meter - Manual (Page 21)

www.ets-lindgren.com Operation 21
4.0 Operation
Before connecting any components, follow the
safety information in the ETS-Lindgren
Product Information Bulletin included with your
shipment.
Do not use without spacer cone in place.
About Zeroing
Zeroing determines the offset value that will be subtracted from all subsequent
measurements.
RF must not be present in the vicinity of the probe when the zero
switch is activated, or it will result in an inaccurate zero.
There are three ways to zero a probe connected to the HI-1710A Microwave
Measurement System:
 Press the ZERO button on the front panel.
 Send the serial port command Z.
 Attach an external device to the ZERO connector on the back panel.
The zero will drift as the electronic circuitry and diodes warm up to normal
operating temperature. There will also be small variations as the ambient
temperature changes during the day. For these reasons, the zero point must be
reset periodically.
In addition, the bias and offset readings are checked against preset internal limits
each time the zero switch is activated. If the limits are exceeded, an error
message is displayed. Zeroing in a sufficiently high RF field or zeroing with the
probe removed will also cause an error. These tests measure the performance
characteristics of the probe and serve as failure indicators.