ADJUSTMENT
X86 Circuit Adjustment Specification (K, R, H type)
Item 1. Adjusting image detection coil L103 Adjustment Method & Value 1. Turn VR101 [RF-AGC] counter-clockwise as much as possible. 2. Impresss sDC2.0V to TP [IF AGC] (IC101 #36). 3. Input fo=45.75MHz Mod=1KHz AM60% Level=100dBµ to TP [IF] (CF1 #1). 4. Observe the waveform of TP [VIDEO] (IC101 #8) using an oscilloscope, and adjust L103 so that the output level is at the maximum.
Maximu
Condition � ANT no signal � If the waveform is clipped, raise the DC voltage somewhat. � AC range
2. Adjusting audio detection coil L101
1. Turn VR101 [RF-AGC] counter-clockwise as much as possible. 2. Input fo=41.25MHz non-modulated Level=94dBµ to TP [IF] (CF1 #1). 3. Connect a voltmeter to TP [SIF] (both ends of R107) and adjust L101 to 0V ± 0.01V. 1. Turn VR101 [RF-AGC] to clock-wide direction as much as possible. 2. Input RF signal 30dBµ 11CH color bar to ANT input terminal. 3. Audio (P/S-6dB) non-modulated. 4. Connect a voltmeter to TP [IC101 #12] and adjustVR102 [SMET] to 3.5V ± 0.05V. 5. Set RF signal 70dBµ and adjust VR101 [RF-AGC] so that the value of the voltmeter connected to TP [IC101 #12] is 4.6V ± 0.05V. 1. Connect frequency counter to PIN1 of CN5 [IC2 #7]. 2. Connect Pin3 [IC2 #8] of CN5 and Pin2 [GND]. 3. Adjust VR1 [15KHz] and set to 15734Hz ± 100Hz.
