Motorola BHA-100S/P-R 用户手册

Figure 2-2 illustrates a functional block diagram of both the forward amplifier and the optional 

return amplifier, and applies to all models. 

RF

output

Preamp

Postamp

Gain

Slope

Attenuator

(plug in)

Attenuator

(plug in)

Attenuator

(plug in)

Equalizer

(plug in)

Equalizer

(plug in)

-20dB

test point

+24Vdc

test point

-20dB

test point

-20dB

test point

Return amplifier

(plug in)

Switching

power

supply

+24Vdc

90-240Vac

2.5A/250V

5A/125V

H

L

H

L

RF

input

-20dB

test point

 

The forward amplifier consists of a low noise pre-amplifier followed by a power-doubled output 

stage to achieve low distortion. Between the two stages there are gain and slope controls for 

level adjustment. 
The input signal level to the pre-amplifier is controlled by a vari-losser with a range of 6 dB. 

The vari-losser is controlled by the 

GAIN 

potentiometer. A JXP-*B socket is also incorporated in 

the signal path to further reduce input signal amplitude. SFE-100-* cable equalizers can be 

installed in the socket to supplement the slope control network. 
A –20 dB directional coupler test point at the amplifier input monitors forward input signal 

levels. Directional coupler test points are also available to measure forward amplifier output, 

return input, and return output signal levels.