Harman Kardon AVR130 - Issues

[R_J]

Re: Harman Kardon AVR130 - Issues

The memory backup I believe is that 3.6 volt battery. Thats the POWER_H line, it has no voltage because the amp is off. that does NOT mean the micro is bad. at least yet. Near the battery is IC85, 3 pin reset chip, what are the voltages on it? one pin is ground (3) pin 2 is input (should be around 3 volts) output is pin 1
It could be the micro is being held in reset and not allowed to run
Reset pin(77) connects to J706, what is the voltage on that line

[revelations]

Re: Harman Kardon AVR130 - Issues

The memory backup I believe is that 3.6 volt battery. and where does J705 connect to? from what I can tell it goes to FUNC_MUTE pin on the micro, so it may not have any voltage on it

Hmm i believe it splits off before it goes there directly to J700 (image attached) i might be wrong.

Ill have a look and see what voltage is on those near IC85

[R_J]

Re: Harman Kardon AVR130 - Issues

I made a mistake tracing the line then made an edit, read #41 again
you say you " found damage near screws " what kind of damage? cracked pc board?

[revelations]

Re: Harman Kardon AVR130 - Issues

I made a mistake tracing the line then made an edit, read #41 again
you say you " found damage near screws " what kind of damage? cracked pc board?

So ive testen them, J706 goes from - 3volt to 2 volts then 5volts then back to - 3volts it's a cycle the whole time. Same for IC85 pin 1, pin 2 is 1.8volts and pin 3 is zero(ground)

And it's not cracked just visible contacts, see photo, same for the display it had 3 pins lose, and the small voltage regulator near the small transformator same issue, ive fixed those. but still a bit weird..

here's a video of pin 3 of IC85

https://youtu.be/ec7z0PVh4dg

[R_J]

Re: Harman Kardon AVR130 - Issues

That reset pin should not be cycling, I think if the battery was at 3.6 volts, that might cause the reset from cycling, maybe then the amp might turn on?
It's a good chance all that was wrong originally were those bad connections on the display???

[revelations]

Re: Harman Kardon AVR130 - Issues

That reset pin should not be cycling, I think if the battery was at 3.6 volts, that might cause the reset from cycling, maybe then the amp might turn on?
It's a good chance all that was wrong originally were those bad connections on the display???

Yes i believe so, it powered up fine, except the display. so if i had seen that before and fixed the 6 pins it might have simply worked.

So if i understood correct, you are saying that its resetting the whole time? meaning IC72 won't do anything because before it has the chance its being reset?

If so, would there be a way to stop the reset (disable the reset temporary?)

And that battery, i could see if there's a replacement for it. It's now 1.9volts

Those pins on the photo are the ones that where broken.

[R_J]

Re: Harman Kardon AVR130 - Issues

The microprocessor (ic72) needs to be reset once after it see's power, if it is constantly being reset, the program starts and before it can continue it is reset back to the start position. the program never gets a chance to run completely, so it may never reach the point in the code that reads the line for the key_1 (standby button)
If you get a battery in place and the reset is not fluctuating, you may need to do a master reset before the amp operates

[revelations]

Re: Harman Kardon AVR130 - Issues

How does a masters reset works? The battery is a 3.6volts 40mah is it possible I can replacement that with a higher mah? As long as the volts are the same ofcourse

[R_J]

Re: Harman Kardon AVR130 - Issues

Yes to the battery and I thought you already did a master (Processor) reset once? If not the procedure is on page 13 of the manual
with power indicator (amber) press and hold the Tone Mode Button for three seconds

[revelations]

Re: Harman Kardon AVR130 - Issues

Oh yes I thought a special reset haha, alright ill look for a new battery first and let you know!

[revelations]

Re: Harman Kardon AVR130 - Issues

So ive bought another Harman kardon avr 130 one that works and testen it's battery. It's exactly 3.6volts. So Somehow that other battery got toasten. Ill replace it and hope for the best.

[revelations]

Re: Harman Kardon AVR130 - Issues

New battery installed bit thick but fits. However it's not turning on. And I tried the master reset wich didn't do it either. I did notice the reset pin is now stable and not cycling anymore.

Also not sure what to do with those 4 pins they aren't solderen together on the new machine I bought. However they are on the older one. Not sure if it can harman if I resolder those pins?

[R_J]

Re: Harman Kardon AVR130 - Issues

What are the pins on? a plug or the display? The picture does'nt tell me what they connect to.
So what is the voltage on the reset pin now?

[revelations]

Re: Harman Kardon AVR130 - Issues

What are the pins on? a plug or the display? The picture does'nt tell me what they connect to.
So what is the voltage on the reset pin now?

ill make a photo of that situation.

The reset pin has 3.4voltage now and doesn't cycle. so i think thats cleared

[revelations]

Re: Harman Kardon AVR130 - Issues

What are the pins on? a plug or the display? The picture does'nt tell me what they connect to.
So what is the voltage on the reset pin now?

1 of the 4 pins is connected to C891 the other 3pins are attached to the display.

[R_J]

Re: Harman Kardon AVR130 - Issues

Those are the filament pins for the display, Is the display working? They should be connected, soldered. They are pins 102,103,104, of fip1 on page 108 (you said 4 pins I only see 3) They could only be making a partial connection if the display is actualy on.
Since you now have another machine to compair, what is the reset line voltage on the working unit, it might be worth monitoring that line when the unit is first pluged in and see if it changes.

[revelations]

Re: Harman Kardon AVR130 - Issues

Those are the filament pins for the display, Is the display working? They should be connected, soldered. They are pins 102,103,104, of fip1 on page 108 (you said 4 pins I only see 3) They could only be making a partial connection if the display is actualy on.
Since you now have another machine to compair, what is the reset line voltage on the working unit, it might be worth monitoring that line when the unit is first pluged in and see if it changes.

No idea if the display is working.

Regarding the reset pin, ive checked it again on both machines. the voltage on PIN 1 and 2 are 3.2/3.4voltage for both AVR's so i guess thats correct?

I was wondering, could it be that the system is in protection mode due to a failure somewhere on the main pcb maybe?

[R_J]

Re: Harman Kardon AVR130 - Issues

Also not sure what to do with those 4 pins they aren't solderen together on the new machine I bought. However they are on the older one. Not sure if it can harman if I resolder those pins?

I thought this was on the new machine, but the picture showed a working display. So is the one with the display in the picture the new machine or the old machine?
I don't think it is in protect mode, but that Master reset should get around that I would think, You could swap front panels between the amps.
With the pins in the picture the way they are you will NOT get a display, why don't you solder them to the board and see if the display works, it might give a clue as to where to look next.

[revelations]

Re: Harman Kardon AVR130 - Issues

I thought this was on the new machine, but the picture showed a working display. So is the one with the display in the picture the new machine or the old machine?
I don't think it is in protect mode, but that Master reset should get around that I would think, You could swap front panels between the amps.
With the pins in the picture the way they are you will NOT get a display, why don't you solder them to the board and see if the display works, it might give a clue as to where to look next.

Sorry no that was on the old machine, ive soldered those, but i don't know if its correct ofcourse.

So here is what i just did. I took off the front panel of the broken machine and swapped it with the working machine. Result = Front panel not turning on (except standby amber)

So then i put the original front panel back on the working machine and that works fine ofcourse.

I guess that tells us for sure something is wrong with the front panel of the broken machine.

[R_J]

Re: Harman Kardon AVR130 - Issues

You say you soldered them but they may not be correct?, it's only 3 connections, and they are connected together. If they are soldered correctly you should have the fillament light up in the display (can be hard to see) or measure the a/c voltage going to the display. those are the 3 pins on either side of the display tube. and should be about 8.4 volts ac.
Did you try the working front panel on the non working amp? to see if the rest ofthe unit is working.