BIRD THRULINE 43 Series, Instruction Book

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To maintain accuracy, it is important to have operating frequencies within
those stated.
The elements for the Model 4330 have a dual power range. The slide switch
on the face of the element is moved sideways to select either 800 mW or 200
mW full scale deflection as indicated by the element nameplate. The scales
on the meter dial coincide with the position selected. For protection of the
meter, always select the higher value first. Do not switch to the lower position
when a higher power is indicated in the direction selected.
The following parts are applicable to the Model 4330 and are different from
those listed for the Model 43. All other parts not listed here are applicable.
Model 4330/31 Replacement Parts List
Model 43P Peak Wattmeter
The Bird Model 43P Thruline Wattmeter is capable of measuring peak power
in AM, SSB, and certain limited pulse applications. It also possesses the
Model 43’s ability to measure CW power (no amplitude modulation) with just
the press of a button.
No special elements are required for peak power measurements. However,
element power rating must match the peak power to be measured. For
example, if power output peaks of 1000 watts are to be measured, a 1000
watt element must be used in the line section port.
Item Description Part Number
1
Housing assembly 4330-004
2
Microammeter, 10
µ
A full scale, 3-1/2"
rectangular
2160-027
3
Meter cable assembly 33" cable e/w
spade lugs and dc connector 4220-097-12
Bird Model 43 Wattmeter
46