Question about Audio Players & Recorders

1 Answer

I have a Sony STR-DE945 Receiver with no sound coming out. During troubleshooting, I found two bad output transistors which I replaced. I also added jumper wires between the display board, power board, muting board, and volume control board to bypass the failing connectors. Everything seems to power up fine, I hear the output relays click, but no sound. Even the built-in diagnostics tests from the service manual pass. I also checked the +/-15V and 5V supplies to all of the boards. Any ideas what to try next?

Posted by on

Ad

1 Answer

  • Level 1:

    An expert who has achieved level 1.

    Hot-Shot:

    An expert who has answered 20 questions.

    Corporal:

    An expert that hasĀ over 10 points.

    Mayor:

    An expert whose answer gotĀ voted for 2 times.

  • Contributor
  • 30 Answers

I had a similar problem with my denon AV amp all it was were 2 little resistors but I had to scan through a lot as it was after the power supply and in the main bd

Posted on Feb 15, 2014

Ad

2 Suggested Answers

6ya6ya
  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi,
a 6ya expert can help you resolve that issue over the phone in a minute or two.
Best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
New users get 2 Free calls (no credit card required) and instant help on almost anything you can think of (from cars to computers, appliances, handyman, and even pets).
click here to download the app (for users in the US for now) and get all the help you need.
Goodluck!

Posted on Jan 02, 2017

Ad
electrotech1
  • 1126 Answers

SOURCE: I am troubleshooting a HTR-5830

Check for shorted out put transistors that is pulling your voltage down.

Posted on Dec 22, 2010

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

I have a sony STR-DE945, and no sound was put out unless you pushed in the power button slightly. Now no sound comes out no matter what. Was going to replace the circuit board part no. 1-676-999-1 but part...


unfortunately, electronics go obsolete very quickly, and the cost to repair a specific unit is so close to that of purchasing a new replacement that very few places stock parts or do repairs these days.

Unless electronics repair is a passion or hobby of yours, you will spend much time and effort trying to get parts, time trying to replace the defective parts (a waste of time and money if you aren't absolutely certain which parts are bad).

Since the complete board is no longer available, troubleshoot to the compnent level and replace the individual items on the defective board, or just get a new receiver.

Aug 11, 2014 | Sony STR-DE945 Receiver

1 Answer

Can I get digital output through my STR-DE945,


Register and download the manual for free at retrevo.com


http://www.retrevo.com/support/Sony-STR-DE945-Receivers-manual/id/387dj982/t/2/


The far left optical connector on the back is an output.

Feb 21, 2011 | Sony STR-DE945 Receiver

2 Answers

Please tell me how to remove the fan from the receiver it has stopped working causing the unit to go into a Protect-Fan mode thanx for any help John


hello the reason the fan has stop working may be down to the output transistor shorted out or a swelled capacitor

regards
shaun

Sep 12, 2010 | Sony STR-DE945 Receiver

1 Answer

I have a sony STR-de135 receiver whlie looking for one problem created another.While the receiver was unpluged I touched and output transistor MN2488 and it sparked now the left channel sounds distorted so...


The capicitors in the unit are charged. Replacing the output transistor(s) is not a task for a novist. Capicitors, resistors, driver transistors and sometime preamp chips can also be bad as well. If all the bad components are not replaced the parts you replace could blow out again.

Jun 19, 2010 | Sony STR-DE135 Receiver

1 Answer

How to verify which transistor is creating protection mode?


Take your ohm meter and measure the outputs one by one. with the power unplugged and the main board flipped to access this circuit. If they all check the same , no shorts , then You may have a preamp driver failure. Larry's Electronics ledstiles@hotmail,com

Apr 25, 2010 | Sony STR-DE945 Receiver

1 Answer

Have a str-de 945,unit was working,sound stopped,still powers up.Replaced 2, 8 a fuses,blew again,nothing was connected to the unit.The heavy power supply unit in the front seems to have a hard orange...


Chances are you have shorted output transistors,check with ohm meter across all 3 legs,there should be no shorts if good.. cost on average around 150.00

Apr 16, 2010 | Sony STR-DE945 Receiver

1 Answer

Sony Str-DE945 5.1 not Powering Up all !


It's possible there are several bad solder joints on the front panel PC Board which can cause non responding controls, loss of sound. I repaired mine that way. Try turning it on with remote, see if that works.

Oct 21, 2008 | Sony STR-DE945 Receiver

4 Answers

STR-DE945 stuck in auto protect mode?. I'm pretty sure it is the output capacitors but I do not Know where they are located to change them.


First of all my STR-DE845 started having the protector problem about 6 months ago and I bought this receiver back in 2001. This is what I found wrong with mine. After searching online I found a service manual for the receiver, this came in handy when diagnosing the problem. The first obvious thing was discoloration of the board around the IC 501, 601, and 701 Op-amps. When looking at the receiver from the front these are the three vertical NEC ICs to the right of the main amplifiers. Even with no load these amps get very warm. Sony failed to add any heat sink to these ICs so eventually they can de-solder themselves, specifically the 701 IC which is the one closest to the back of the unit. With mine I was able to slightly push the 701 more vertical, since it was leaning, and I believe it has helped it make a better contact. The protector circuit will kick in if it senses the Op-amps are shorted or not making contact. The best solution is to add some copper heat sink to these ICs, they already have screw slots for a heat sink. If they ever fail you will have to get new op-amps and re-solder them to the board. Hope this helps.

Jan 17, 2008 | Sony STR-DE845 Receiver

Not finding what you are looking for?
Audio Players & Recorders Logo

Related Topics:

40 people viewed this question

Ask a Question

Usually answered in minutes!

Top Audio Players & Recorders Experts

kakima

Level 3 Expert

102366 Answers

 Grubhead
Grubhead

Level 3 Expert

5151 Answers

The Knight
The Knight

Level 3 Expert

74383 Answers

Are you an Audio Player and Recorder Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...