Service manual

5. Terminal Function Table
56
NOTE :
• Terminal form abbreviations : EE : emitter follower, P-P : push pull, B : base, C : collector.
• All figures are measured at Vcc = 9V at no signal condition.
• All figures show standard values.
Terminal No. Description Function
Terminal
Termanal Form
Voltage
1 HEAD EQ Selecting swiitch of condenser 0.0V 220kΩ/27Ω(ON)
for head resonance
2 PB IN PB AMP input/PB side head switch 3.4V REC : 120kΩ
REC : 11Ω(ON)
3 REC HSW REC side high voltage head switch 0.0V REC : 11Ω(ON)
REC : OPEN
4 GND GND (for PB AMP, Head switch) 0.0V –
5 RIPPLE FILTER Ripple filter 9.0V 10kΩ(Vcc)
6 PB NFB PB AMP fecdback 3.5V B(NPN)
7 Vcc Vcc 9.0V –
8 PB EQ PB EQ selecting switch 3.5V 55Ω(ON)/OPEN
9 EQ CTRL EQ control –
10 PB OUT EQ AMP output 3.5V EE
11 PB/TU/EE CTRL PB/TU/EE control –
12 PB LINE IN Line input for PB 4.1V 120kΩ
13 ALC LEVEL ALC Level setting terminal – B(PNP)
14 ALC FILTER Terminal for ALC filter with time PB : 0.0V EE(NPN)~220Ω
constant PB : vari-
(Setting attack and recovery time) able
15 BIAS Bias 4.1V EE(NPN)
Isink = 670µA
16 LINE IN Line input 4.1V 120kΩ
17 MUTE CTRL MUTE control –
18 TUNER IN Tuner input 4.1V 120kΩ
19 REC NFB REC AMP feedback 4.1V B(NPN)
20 GND GND 0.0V –
21 REC OUT REC AMP output 4.1V EE(P-P)
22 BF OUT Line AMP OUTPUT 4.1V EE(P-P)
23 REC EQ REC EQ selecting switch 0.0V 100kΩ/22Ω(ON)
24 REC/EE CTRL REC/EE control –