Master Electronics Repair !

Welcome to Master Electronics Repair! website.Here you will find:Service Modes, Circuit Diagrams,Service manuals, Firmware Update procedure, Disassemble procedure, Universal remote control setup codes, Troubleshooting, Diagnosing, Measuring, and more.... of many of LCD/LED TV/Displays,others various electronic apparates,trough many technical notes and tips/tricks to help repairing/fixing Troubles/ faults,for electrical technicians.This site helps you to save the Earth from electronic waste!

Richtige Fernseher haben Röhren!

Richtige Fernseher haben Röhren!

In Brief: On this site you will find pictures and technical information about Service Modes, Circuit Diagrams, Firmware Update procedure, Disassemble procedure, Universal remote control set-up codes, Troubleshooting and more....

If you go into the profession, you will obtain or have access to a variety of tech tips databases HERE IT IS Master Electronics Repair !.

These are an excellent investment where the saying: 'time-is-money' rules. However, to learn, you need to develop a general troubleshooting approach - a logical, methodical, method of narrowing down the problem. A tech tip database might suggest: 'Replace C536' for a particular symptom. This is good advice for a specific problem on one model. However, what you really want to understand is why C536 was the cause and how to pinpoint the culprit in general even if you don't have a service manual or schematic and your tech tip database doesn't have an entry for your sick TV or VCR.

While schematics are nice, you won't always have them or be able to justify the purchase for a one-of repair. Therefore, in many cases, some reverse engineering will be necessary. The time will be well spent since even if you don't see another instance of the same model in your entire lifetime, you will have learned something in the process that can be applied to other equipment problems.
As always, when you get stuck, checking out a tech-tips database may quickly identify your problem and solution.In that case, you can greatly simplify your troubleshooting or at least confirm a diagnosis before ordering parts.

Happy repairing!

Today, the West is headed for the abyss. For the ultimate fate of our disposable society is for that society itself to be disposed of. And this will happen sooner, rather than later.

How to use the site:

- If you landed here via any Search Engine, you will get what you searched for and you can search more using the search this blog feature provided by Google. You can visit more posts scrolling the left blog archive of all posts of the month/year,
or you can click on the main photo-page to start from the main page. Doing so it starts from the most recent post to the older post simple clicking on the Older Post button on the bottom of each page after reading , post after post.

You can even visit all posts, time to time, when reaching the bottom end of each page and click on the Older Post button.

- If you arrived here at the main page via bookmark you can visit all the site scrolling the left blog archive of all posts of the month/year pointing were you want , or more simple You can even visit all blog posts, from newer to older, clicking at the end of each bottom page on the Older Post button.
So you can see all the blog/site content surfing all pages in it.

- The search this blog feature provided by Google is a real search engine. If you're pointing particular things it will search IT for you; or you can place a brand name in the search query at your choice and visit all results page by page. It's useful since the content of the site is very large.

Note that if you don't find what you searched for, try it after a period of time; the site is a never ending job !

..............The bitterness of poor quality is remembered long after the sweetness of todays funny gadgets low price has faded from memory........ . . . . . .....
Don't forget the past, the end of the world is upon us! Pretty soon it will all turn to dust!

©2010, 2011, 2012, 2013, 2014 Frank Sharp - You do not have permission to copy photos and words from this blog, and any content may be never used it for auctions or commercial purposes, however feel free to post anything you see here with a courtesy link back, btw a link to the original post here , is mandatory.
All posts are presented here for informative, historical and educative purposes as applicable within fair use. NOTHING HERE IS FOR SALE !

Saturday, 9 March 2019

PANASONIC SA-AK350PL CIRCUIT DIAGRAM POWER AMP AND POWER SUPPLY

PANASONIC SA-AK350PL

CIRCUIT DIAGRAM POWER AMP AND POWER SUPPLY

EEPROM Checksum (ROM Correction)
Purpose: To check for microprocessor firmware version and EEPROM checksum (ROM correction)

Below are the procedures for this mode.
Step 1: Enter into Doctor mode (for more information, refer to section 9.2 on the key operation to enter into this mode.
Step 2: Check for firmware version and EEPROM checksum (By pressing STOP button on main unit followed by “4” and “7” on remote control).
· When entering into DOCTOR MODE, the firmware version and checksum data of EEPROM (if applicable) will appear on FL display. Below is the information on the EEPROM IC (ROM correction) under 3 possible situations:
1. In the case that the correction point existence data is other than 0 (ie. correction file exists), EEPROM checksum display for the microprocessor shall be made after calculating checksum by summing up the content of data area from EEPROM IC.

2. In the case when no EEPROM IC is installed. It display as no display of checksum data

3. In cases that the filename is different even though a EEPROM is installed, or no correction file exists, [NG] shall be displayed (the correction point existence data is set to 0 at this condition).

Note: Microprocessor firmware refers to version number for microprocessor IC located on PANEL P.C.B.. It is subject to change which would be updated accordingly. ROM correction checksum refers to the HEX code that is displayed upon key buttons pressed if an EEPROM is loaded in the unit.

Error code Table Display
Self-Diagnosis Function provides information on any problems occuring for the unit and its respective components by displaying the error codes. These error code such as U**, H** and F** are stored in memory and held unless it is cleared. The error code is automatically display after entering into self-diagnostic mode.

CRS1 Error Code display
CRS1 Error Code display
1. The errors that occured in CRS1 Mechanism can be recalled and displayed, in the order of the occurence under self-diagnostic
for procedures to enter this mode.
· Only the first 5 errors will be memorized (in backup memory). The subsequence error shall be ignored and not memorize. For system with EEPROM as memory backup,memory space in EEPROM is neccesary.
2. To display all error code memorized In CRS1 Self-Diagnostic mode, press [SINGLE CHANGE] to display subsequence error code. It shall repeat after reaching error no. 5.
e.g.:
[1 _ _ _ _ I H M S] → [SINGLE CHANGE]
[2 _ _ _ _ I T O P] → [SINGLE CHANGE]
[3 _ _ _ _ H O M E] → [SINGLE CHANGE]
[4 _ _ _ _ L O A D] → [SINGLE CHANGE]
[5 _ _ _ _ _ U D D] → [SINGLE CHANGE]
3. To clear the error code memory
In CRS1 Self-Diagnostic mode, long press [SINGLE CHANGE] key (2s or more)

Measurement And Adjustments
Cassette Deck Section

Requirements
· Test tape (QZZCFM) (QZZCWAT)
· Normal blank cassette tape (QZZCRA)
· Digital frequency counter
· Oscilloscope
· Electrical voltmeter
· Headphone jack output jig

Setting of Unit
· VOLUME: MAX

Preparations].
1. Remove 4 screws from the mechanism unit to disassemble
2. Connect the headphone jack output to headphone jack.

Tape Speed Adjustment
· Normal speed adjustment (only during forward playback)
(Product reference value: 3,000±90Hz)
1. Connect a frequency indicator.
2. Playback the middle portion of the test tape (QZZCWAT).
3. Adjust the motor screw so that the following output level is produced.
Adjustment Range: 3,000 ± 90Hz (a constant speed)

Bias Voltage Check
1. Connect an electrical voltmeter. (Fig 12) (Fig 9 for location of test point)
2. Set the function to “TAPE” position.
3. Insert a normal blank cassette tape (QZZCRA).
4. While pressing and holding down [REC/PAUSE] button, press [TAPE( PLAY )] button to pause the recording mode. (Repeat pressing the buttons till the recording pause mode is activated.)
5. Check that the output level is within the standard range.
Standard Range: 16 ± 3M