Re: Harman Kardon AVR 171S - standby led lights up, does not turn on
You have to measure, even with an oscilloscope, and look for oddities and anomalies.
Unfortunately, I can't say more, but maybe another forum member can give me an idea.
I change the e.capacitors first, they are the first ones that generally break down.
If it doesn't help, I'm looking for a heating part.
If there is, and it is suspected to be faulty, I will replace it without a thinking.
If it doesn't help, the scope and thinking with my hands on the wiring diagram...
madsox
Member
Last Activity: 11-19-2023, 09:58 AM
Joined: 06-21-2020
Location: Hungary, HU
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Re: Harman Kardon AVR 171S - standby led lights up, does not turn on
Where can you short circuit? Anywhere.
Any capacitor, any resistor, IC or transistor can go into short circuit.
I found it by unsoldering the components one by one, measuring, unsoldering, measuring... in the end there was nothing between the +3.3VC and the GND line, only the controller.
Of course, it is worth searching for each part and island.
There is the injection method, but I haven't tried it yet.
With this method, the short-circuited component can...Leave a comment:
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Re: Harman Kardon AVR 171S - standby led lights up, does not turn on
Well.
I measured the digital PCB.
And it's the worst.
The microcontroller have shorted.
How to replace that, I really don't have idea.
Okay, the IC is available, but the program. . .Leave a comment:
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Re: Harman Kardon AVR 171S - standby led lights up, does not turn on
Hello.
Unfortunately, I didn't make it any further, it's been standing for a year.
I found a good solution for a Focusrite sound card, but the topic seems to have stopped.
I tried to ask in other places, without success; the questions stopped just like that, no matter how much I brought them up again and again.
If you manage to get any information, I would be very grateful if you could pass it on to me.
...
Although, now I'm at home sick,...Leave a comment:
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Re: Harman Kardon AVR 171S - standby led lights up, does not turn on
No, the amplifier has 2 wired fans.
On the ali' control panel, the fan pwm leg is connected with the input connector pwm pin, it is not used to speed control.
Or what are you thinking?...Leave a comment:
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Re: Harman Kardon AVR 171S - standby led lights up, does not turn on
I did not find any reference in the service manual or user manual to any self-test function.
Thank you.Leave a comment:
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Re: Harman Kardon AVR 171S - standby led lights up, does not turn on
The temperature sensor was mounted on the power supply (on the 12V voltage stabilizer) instead of the heat sink of the amplifier transistors.
Someone tried to fix the amplifier before me, I wasn't the first.
If that doesn't help, I'll install a fan controller ([url]https://www.aliexpress.com/item/1005004752252602.html[/url]) for proper cooling.
They have worked great for my computers, it will be good here too if the built-in controller is faulty...Re: Harman Kardon AVR 171S - standbyLeave a comment:
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Harman Kardon AVR 171S - standby led lights up, does not turn on
Greetings!
Thank you in advance for your understanding, I am writing to you through a translator.
A Harman Kardon AVR171S amplifier was given.
The history of the machine is as follows:
It was faulty when I bought it, I want to fix it.
I replaced the HDMI switch and one of the DAC ICs in it.
After that it worked without a problem.
I watched a movie using the amplifier, and at the end the amplifier got really hot.
The cooling was faulty, I will fix this later.
I switched it to standby mode, waited for... -
Re: Focusrite Saffire Pro 40 re-cap
I don't have image from power supply now, but if you have patience, i make on weekend.
Leave a comment:
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Re: Focusrite Saffire Pro 40 re-cap
Hello everyone!
Today come the last needed part, FQPF8N60.
After soldered, it's working.
Many thanks for help!
Tamás'...Leave a comment:
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Re: Focusrite Saffire Pro 40 re-cap
Thank you very much for the data and here is the picture.
Sorry for the delay....Leave a comment:
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Re: Focusrite Saffire Pro 40 re-cap
Hello everyone!
If anyone would please and be able to upload lots and lots of pictures of a Saffire Pro 40 power supply, I would be very grateful.
I bought a used device that is missing some parts.
What it does is completely different from what you see in some of the pictures on the internet.
Whats missing:
D1, D2, D3, D4, D10
C3, C11, C12, C13, C14, C15
If someone writes me a list of the value of these, that’s more than enough.
Thank you very much!Leave a comment:
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Re: New Members - please post your introductions here
Hello everyone! Thank you in advance for all your help!Leave a comment:
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