Table 12-5 lists the RF Section mnemonics shown in Figure 12-8, and provides a brief description of each.

Table 12-5. RF Section Mnemonic Table

Mnemonic

Description

 

 

TUNE+, TUNE-

YTF Tune Signal (SYTF or RYTHM)

HTR+, HTR-

YTF Heater Power

 

MAIN COIL+, MAIN COIL-

YTO Main Coil Tune Signal

FM+, FM-

YTO FM Coil Tune Signal

LO SENSE

LO Amplitude Sense

Voltage

LEVEL ADJUST

LO Amplitude Adjustment Voltage (PIN ATTEN)

GATE BIAS

LODA Gate Bias Voltage

HEXTMIXB

External Mixer:

+12V=EXT MIX

 

 

- lZV=INT MIX

HSIGIDOFFA

SIG ID Oscillator ON: +lSV=SIG ID OFF

 

 

-8V=SIG ID ON

PIN SW

PIN Diode Switch Control (SYTF or RYTHM LO Band/HI Band)

PIN DIODE SWITCH

PIN Diode Switch Control For 2ND Conv. IF Output

MIXER BIAS

Detected Voltage on 2ND Converter Mixer Diode

RFGAIN

Voltage to Control Gain of Flatness Comp. Amps.

RFGAINl and RFGAIN2

Currents to Drive PIN Diodes in Flatness Comp. Amps.

LlOdB A, L40dB B, LSOdBC, LDC D

Control Lines to Set Attenuator Sections A, B, C, and D

 

to Attenuate Position (Active Low)*

1OdB A, 40dB B, 20dB C, LAC D

Control Lines to Set Attenuator Sections A, B, C, and D

 

to Attenuate Position (Active High)*

 

 

 

*Section D of the input attenuator is a dc blocking capacitor which is switched in or bypassed by the LDC D and LAC D control lines.

RF Section 12-23

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Image 449
Agilent Technologies 856290216 service manual RF Section Mnemonic Table