Service, LCD Negative Bias Generator | Ericsson LPE-200 specs

AE/LZB 119 1902 R1A

LCD NEGATIVE BIAS GENERATOR

A 96 kHz, 5V p-p square wave from HILLARY D701- 57 is rectified and inverted to a negative supply voltage by C922, V909 and C923. This negative voltage is controlled to the LCD by V910 to vary the display contrast. Thermistor R604 is monitored via the A/D input to DEBBIE. As the temperature varies, the bias is varied using

4 binary output lines from HILLARY:

∙LCD_BIAS 0

∙LCD_BIAS 1

∙LCD_BIAS 2

∙LCD_BIAS 3

SERVICE

Due to the state of the art manufacturing processes and the complexity of the circuits designed into the radio, field test and repair to the hardware is very limited. It is not practical to service the main circuit board in this radio to component level. Technicians servicing this radio should be concerned with isolating the problem to hardware or software. Software errors or problems are usually corrected by reloading the personality, flash, etc.

NOTE

It is recommended that all hardware repairs to the main circuit board be done at Ericsson Inc. in Lynchburg, VA.

On occasion it may become necessary to perform certain hardware repairs in the field. Therefore, Service Parts will provide replacement parts for the following hardware items:

∙	Flex Assembly	∙	Keypad
∙	Loudspeaker	∙	Vol/Grp Switch Module
∙	Battery Connector	∙ Rx RF Filter (Z400)
∙	PA Module	∙ Rx RF Filter (Z401)
∙	DSP Module	∙	Fuse

∙Main PCB Assembly

Keeping in mind the service philosophy for this product, it is not the intent of this service section to provide detailed instructions for testing and troubleshooting the portable radio. This section will provide the following:

∙Programming instructions (Personality, Flash and Equipment Setup)

∙Basic Troubleshooting (determine if problem is hardware or software)

∙Error Codes

∙Dissassembly

EQUIPMENT REQUIRED

	Equipment Description	Part Number

1. ProGrammerTM Programming		AE/LZY 213 7641
	Software

2. Programming Interface Module		TQ-3370
	With Power Supply	(19D438367G2)
	(19B800850P2)
3. Programming Cable		TQ-3368
		(19B801971P3)

4.	RS-232 Cable	19B235027P1

5.	Test Box	TQ-0609A

6.	Test Cable	19B801971P6

7.	Radio Test Set	customer supplied

8.	IBM PC/XT/AT/286/386/486 or	customer supplied
	any true compatible with MS-
	DOS version 3.3 or later.

PROGRAMMING

Personality Programming

The ProGrammer PC Programmer (AE/LZY 213 7641) Version 1 or later is used to edit, read or write the personality to the radio. A personality is simply a computer file generated (created) by the user of the program. The computer file (or personality) is downloaded into the radio and contains data that will direct certain operating characteristics of the radio unit.

The PC Programming software communicates with the radio through the TQ-3370 programming box (item 2 in the equipment list). Figure 7 provides a diagram of the Equipment Setup required to PC Program the radio.

The CONV-1 PC Programmer (TQ-3367) Version 12 or later is used to program conventional only radios.