Receiver Rf Circuitry - Uhf Reciter; Front End; Figure 2.7 Reciter Uhf Receiver Rf Circuitry Block Diagram - Tait TB8100 Service Manual

2.4

Receiver RF Circuitry - UHF Reciter

Figure 2.7 Reciter UHF receiver RF circuitry block diagram
H and K Bands
RF In
Band Pass
Filter 1
Mixer
L Band
SAW
RF In
Filter
Switch
SAW
Filter
Attenuator
Pad Mixer
2.4.1

Front End

H-Band Reciter
42 Reciter Circuit Description
RF Low Pass
Amplifier 1 Filter Attenuator
AGC Control
Post-mixer
Diplexer Buffer
Local Oscillator
Low Pass
Switch Filter Amplifier
Post-mixer
Diplexer Buffer
Local Oscillator
The incoming signal from the BNC connector is fed through a triplet helical
filter, followed by a simple low pass network which attenuates harmonics
and spurious responses from the preceding filter. The signal is then
amplified and passed through a low pass filter which provides immunity to
interference from higher frequency out-of-band signals. Automatic gain
control (AGC) is provided at this point by a PIN diode attenuator. The
signal is now amplified again in a second RF amplifier, and is then fed
through a band pass filter and attenuator pad to the mixer.
PIN RF Band Pass
Amplifier 2 Filter 2
AGC not fitted to
AGC Detector
K band reciters
Attenuator Crystal
Pad Filter
RF Low Pass High Pass
Filter Filter
Attenuator Crystal
Pad Filter
© Tait Electronics Limited September 2006
Attenuator
Pad
IF Anti-alias
Amplifier Filter
IF Output
SAW
Filter
Switch
SAW
Filter
IF Anti-alias
Amplifier Filter
IF Output
TB8100 Service Manual
Switch