Fluke 943-227-15, 943-27 manual Test Point Function, RS232 Transmit

943-227-15 Digital Preamplifier

Operator Manual

The following Test are provided on the 977-200-15M board:

Table 2-4. 977-200-15M Test Points

Test Point	Function
TP1	Electrometer Output
TP2	Analog +5 VDC supply
TP3	- 5 VDC supply
TP4	Digital +5 VDC supply (From 977-210-10M)
TP5	High Voltage Sense (Not Used)
TP6	+ 12 VDC supply (From 977-210-10M)
TP7	DC Ground
TP8	Programmable Gain Amplifier Output
TP9	Microprocessor Clock Signal
TP10	Chip Enable - EPROM

2.4 977-210-10M Interface Board

Refer to the Communications Interface, P/N 977-210-13M, schematic diagram in Appendix B. U12 is an asynchronous communications interface adapter (ACIA) which communicates with the UDR or 960 system. U1 is an analog switch used to select either the Victoreen loop or the RS232 driver/receiver for external communications. Optical isolation U10 isolates data transmitted on the Victoreen loop while the circuitry comprised of Q6, Q7, Q14, and Q18 are the actual loop drivers. Optical isolator U8 isolates the receive data from the Victoreen loop.

U2 and U3 are, respectively, the receiver and driver circuits for the RS232 port. U14 decodes address block A000 to provide chip enables to the ACIA switch input register U6.

Regulated power for the electronics (+/- 12 VDC) is derived from three terminal regulators VR3 and VR4. The ±5 Vdc logic power is derived from the three terminal regulators VR1 and VR2.

Power for the detector is normally provided by the electronic high voltage power supply in the associated Model 942A-200C UDR or Model 960 System.

The following LEDs are provided to indicate operation of certain functions of the 977-210-10M board:

Table 2-5.	977-210-10M LEDs
LED #		Indicates
LED1		+15 VDC is being supplied to the circuit board
		from the UDR when ON
LED2		Communications – Receive;
		ON (bright): both + 15 and -15 volt loops
		present
		ON (dim): Only one loop supply present
		OFF: no loop voltage from either supply

The following Test are provided on the 977-210-10M board:

Table 2-6. 977-210-10M Test points

Test Point	Function
TP2	RS232 Transmit

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