B&K 1794 instruction manual REF. PCB no PIN no, Parts Ordering & Replacing

5.4.3VOLTAGES AT VARIOUS PINS OF IC LM324 IS AS FOLLOWS ( IC-101 ) :-

IC PIN NO.		VOLTAGES & CHECK CONDITIONS
PIN1	--	0V ( WHEN V POT KEPT AT MIN. POSITION IN CV MODE )
PIN1	--	+5V ( WHEN V POT KEPT AT MAX. POSITION IN CV MODE )
PIN2 & 3--		+4.9V AT V POT MAX. POSITION.
PIN4	--	+12V ALL CONDITION
PIN7	--	0V AT CC POT MIN. POSITION.
PIN7	--	0.5V AT CC POT MAX. POSITION.
PIN8	--	+1V TO 3.5V IN CV MODE.
PIN8	--	+10V TO +11V IN CC MODE.
PIN9	--	0V.
PIN10	--	-6mV.
PIN14	--	+10 TO 11V IN CV MODE.

5.4.4 A.	CHECK VOLTAGES AT D3	CATHODE +2V (CV) +10V (CC)
B.	CHECK VOLTAGES AT D4	CATHODE +10V (CV) + 2V (CC)
C.	CHECK VOLTAGES AT Z101	CATHODE -4.7V
D.	CHECK VOLTAGES AT Z102	CATHODE +10V

5.4.5CHECK ALL REGULATORS OUTPUT WITH RESPECT TO OUTPUT +VE COMMON.

REF. PCB NO.	PART NO.	PIN NO.	VOLTAGES
U1	IC7812	3	+12V
U2	IC79L05	3	-5.0V
U3	IC7805	3	+5.0V
CHECK WITH RESPECT TO OUTPUT -VE AS COMMON.
U4	IC7812	3	+12.0V

All the above readings are approximate values. The given voltages & waveforms are refering to a normal working unit. If find any Voltage or Waveform absent at given points, then trace back to the associated circuits. This complets basic trouble shooting test points.

5.5PARTS ORDERING & REPLACING :

5.5.1OBTAINING REPLACEMENT PARTS : Most electrical parts can be obtained through your local distributor or representative. However you should be able to obtain many of the standard components from a local commercial source in

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