Overview2-3
Forward Amplifier
Figure 2-2illustrates a functional block diagram of both the forward amplifier and the optional return amplifier, and applies to all models.
Figure 2-2
BHA-100* functional block diagram
-20dB | | Attenuator | | | | | -20dB |
test point | | (plug in) | Preamp | Slope | | | test point |
RF | H | | | | | H | RF |
| | | | | |
input | L | Equalizer | Gain | | L | output |
| | |
| | | | Postamp | |
| | (plug in) | | | |
| | | | | |
| | -20dB | | -20dB | | |
| test point | | test point | | |
| | Equalizer | | | | |
| | (plug in) | | | | |
| | Attenuator | | | Attenuator | | |
| | (plug in) | Return amplifier | (plug in) | | |
| | | (plug in) | | | |
| | | | | +24Vdc | | |
| | | | | test point | | |
| | Switching | 5A/125V | | | |
| | | | | |
| | | power | | | | +24Vdc |
| | | supply | | | | |
90-240Vac
2.5A/250V
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.
BHA-100* Broadband House Amplifier Installation Manual