Bird Technologies 6730B Series - Manual (Page 25)

the load when its temperature is between 20 and 25 de-
grees Celsius.
Check and record the dc resistance value of the load be-
fore it is put into service. Use a resistance bridge or ohm-
meter with an accuracy of 1 percent or better at 50 ohms
for this purpose.
If the wattmeter is used frequently, daily to weekly, it is
recommended to check the dc resistance on a monthly
schedule. If the wattmeter is used more infrequently you
may want to set up a six month to yearly schedule ac-
cordingly. If there is no change or even a slight change in
dc resistance there is no cause for alarm. A change
greater than two ohms could be an indication of a failing
load.
These tests are by no means a necessity to the operation
of the wattmeter but merely guidelines for the users in-
formation and advisement.
Checking the wattmeter accuracy consists mainly of com-
paring its reading with the readings of similar wattme-
ters. If other wattmeters are not conveniently available
then return the instrument to the factory for
recalibration. Special calibration and calibration data can
be provided at an additional cost. Consult the factory for
details.
Disassembly
There are no special techniques required for the repair or
replacement of components in these Termaline Wattme-
ters. A screwdriver and a small wrench are the only tools
needed. The paragraphs below outline component re-
moval.
RF
Connector
The connector is a “Quick-Change” design which permits
easy interchange with the use of only a screwdriver. This
process does not interfere with the essential coaxial conti-
nuity of the load resistor RF input or the coolant oil seal.
For replacement, proceed as follows:
1. Remove the four 8-32 x 5/16 round head machine
screws from the corners of the RF connector.
2. Pull the connector straight out of its socket.
Maintenance
17