REPAIRING AND NOT THROWING AWAY

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 !

Wednesday, 15 January 2020

PANASONIC SA DK10 US MODEL DVD STEREO SYSTEM – POWER SUPPLY AND AMP SCHEMATIC DIAGRAMS HOW TO OVERRIDE THE PROTECTION SYSTEM

 

Before Repair and Adjustment:
Disconnect AC power, discharge Power Supply Capacitors C566~C569, C782 and C591 through a 10Ω, 5W resistor to ground.
DO NOT SHORT-CIRCUIT DIRECTLY (with a screwdriver blade, for instance), as this may destroy solid state devices.
After repairs are completed, restore power gradually using a variac, to avoid over current.  Current consumption at AC 120V, 60 Hz in NO SIGNAL mode should be ~650mA.

Protection Circuitry
The protection circuitry may have operated if either of the following conditions are noticed:
• No sound is heard when the power is turned on.
• Sound stops during a performance.
The function of this circuitry is to prevent circuitry damage if, for example, the positive and negative speaker connection wires are “shorted”, or if speaker systems with an impedance less than the indicated rated impedance of the amplifier are used.
If this occurs, follow the procedure outlines below:
1. Turn off the power.
2. Determine the cause of the problem and correct it.
3. Turn on the power once again after one minute.
Note : When the protection circuitry functions, the unit will not operate unless the power is first turned off and then on again.

Power supply: AC 120 V, 60Hz, Area: U.S.A., Canada, Signal system: NTSC

TAPE SECTION : AR2 MECHANISM SERIES

CD SECTION : RAE0152Z-3 TRAVERSE DECK SERIES

1.The traverse deck (optical pickup) is an extremely high precision construction and must not be subjected to impact, excessive vibration, or other types of rough handling.
2. In order to prevent static electricity damage to the laser diode, use a short pin or similar tool to short the optical pickup’s flexible circuit boards after they have been disconnected from the main circuit board.
3. Handle the flexible circuit boards with care; excessive force could cause them to be broken.
4. Do not turn the pre-set variable resistor (for adjustment of the laser power); it has been adjusted at the factory.

Beam source: Semiconductor Laser

Total stereo mode power: 65 W per channel (8 Ω)

Record - playback head: Solid permalloy head

Erasure head: Double gap ferrite head

Disc: DVD-Video

Gear for servicing (jig) information

Head Azimuth adjustment

1. Connect the measuring instrument as shown in Fig.
2. Replace azimuth screws for both forward and reverse direction after removing the screw-locking bond left on the head base.
3. Playback the azimuth adjustment portion(8kHz, -20dB) of test tape(QZZCFM). Adjust the azimuth adjusting screw until the outputs of the L/Rch are maximized.
Make sure that the difference in the peak level between the left and right channels does not exceed 5dB.
4. Perform the same adjustment in reverse playback mode.
Check of the level difference forward and reverse directions
5. Playback the playback gain adjustment portion(315Hz, 0dB) of test tape(QZZCFM). Check if level difference between forward and reverse direction is within 1.5dB.
6. After the adjustment, apply screw lock to the azimuth adjusting screw.

Transistors and Diodes

Power Amp and Power schematic

Transformer circuit diagram

Printed circuit board – Power Amp

Repairing the mechanism is an expertise work.  Please do not try to do it yourself at home.