[Broosk]

Sorry to barge in and slightly changing the topic but I am a bit desperate about this. Does anyone have an idea what the values of C37 is on the main board power supply? This rectifier bridge burned out on me and I need to replace it. I took the burned rectifier bridge out but but in the process I ripped off C37 from the board. Also is there an alternative to fixing this. I would appreciate any info on this.

Thank you

 

[Helkan]

Hi,
At the beginning I would like to write that this is a great thread. A lot of interesting information. I would like to modify my Z5500 but unfortunately I have to deal with a problem first.
A steady squeal (around 6kHz) can be heard from the satellites, whose intensity does not change when turning the volume control. A high pitch noise is heard at every setting (Analog, Optical, Coax), even when all audio sources are disconnected. Apparently this is a factory defect of a certain series of speakers and the fault concerns the electronics in the subwoofer. I unscrewed my speakers but visually all electronic components look like new (especially capacitors) and it has not loosened on the PCB. I have already looked for answers in many foreign forums, unfortunately my question was left unanswered and I would love to fix my Logitechs. I can solder but I do not deal with electronics on a daily basis and I do not know where to start diagnosing / repairing this fault. I will be grateful for any suggestions.
Regards

 

[Turboman]

Hello,

I have a Z5500 that I want to recap the control panel to start out. I'm not very good at what to pick up when considering ESR and ripple current.
I normally order from Mouser, I was wondering if someone could help me on what I should get?

This is what I have picked out for starters on replacing the SMD caps.

https://www.mouser.com/ProductDetai...l57h5%2BWR6x2GL9IQo6XbITuwm1htjAPFOxRuonPDQ==

https://www.mouser.com/ProductDetai...l57h5%2BWRwkharsdXkBRqN58kbc02ijSFiq0oR6mKQ==

https://www.mouser.com/ProductDetai...l57h5%2BWR/z4rXhk7939/sfFIgJqYlbCn4/mirFjBw==

 

[arismfg]

Hi all.

My Z5500 console stopped working properly showing constantly blue squares on the screen with power on (blue light) or off (red light). After looking everywhere, managed to find that the R21 resistor was burnt. Could this be caused due to one of the pins on the VGA output (on subwoofer) being broken (the pin was stucked in the VGA input (on the console cable)? I mean the contact of the broken pin was probably loose. By the way, replaced the R21 resistor and the VGA input (and output) and everything seems to work ok now. But, trying to find the reason why the R21 burnt. If this helps, the voltage on the broken 15 output pin (after replacing the vga output on subwoofer but before replacing the R21 resistor) was 0 volt.

 

[sci666]

Hello, i have a problem with my z5500 as well,

i identified the problem on the LM217T (?) this is the 8v regulator right ?

i measured the voltage on this line with a multimeter and if the pod is on it is about 9,5 volts and fluctuate to 12-13 volts, if i turn the POD of it goes up to 15 Volt !!!!

in my second z5500 everything is fine, every time 7,88 Volt.

so is the problem solved when i swop the LM217T out ? or is some other part the reason for the wrong voltage as well.

strange is, the unit works fine even with the fluctuating voltage, display is getting a bit brighter and some very quit crispy noises comes off the speakers but nothing else.

thanks guys for your reply

 

[sci666]

So, I swapped out the regulator, no effect, so I did it also with the bridge rectifier. (25v 4700uf also) no effect. I gave no idea. Voltage still fluctuate between 13 and 14 volt! And if the pod is turned off about 15 volt! What else can cause this high voltage?

 

[Peppie1980]

Hi guys. I read the entire topic... wow . Lots of info! I did the mod in the woofer with only the 5x OPA1602, and also burnt the R21 and R22 . Also 2 or 3 diodes,since I can measure them both ways now, this should not be possible. After the mod a HUGE loud rumbling came out if woofer and rear right speaker while no sound was on. Turned of unit and looked inside to see some stuff burned. POD ain't working anymore either. I will order the new resistors and so forth to check if it will work again

 

[dman636]

Hello. Like many others I found this after my beloved z-5500 started acting up. I was wondering if anyone could perhaps assist in figuring out what is happening and after reading this thread (most of it anyways) I found that nobody had my exact symptoms but some in another thread had similar issues. Here is my issue: the control pod turns off randomly, sometimes after 30 mins sometimes after 2 days. Otherwise the device is perfect. All that needs to happen to resolve it is to turn it back on. It literally just acts like the power was pressed. Nothing goofy on the control pod LCD. Here is what I tried: I thought it may be overheating as similar users experienced, so I put the pod vents directly on my home air conditioning. Last time it happened the control pod was ice cold to the touch, so not overheating on the control pod. I tried toggling settings (5.1 -> 2.1) changing TV input format. I tried making sure the power cables are isolated. Made sure the connections are solid. Blocked the IR completed from receiving signals. Disassembled to check for noticeable damage. Nothing seems to stop it so far and no other visible indications of a problem. Could it be the sub woofer overheating? Last time it happened i felt the heat sink and it didn't feel hot at all. Any suggestions would be greatly appreciated.

Its important to note that this happened shortly after changing the configuration. I went from 2 speakers and sub to 5 speakers and sub and changed the 2.1 to 5.1 toggle in the back. I have since tried toggling back to 2.1 (unplugging rear speakers from the speaker side) and it made no difference.

 

[Peppie1980]

well, thats interesting.
After reading this entire forum i do know that there are voltage regulators in the woofer casing. they do control the POD's power aswell.
I also know the cable can be a bit of a problem too (dried out, cracks or bent to long in a strange angle)
perhaps the speakers u have attached had a higher or lower resistance (Ohm's) than the unit can handle, and some components broke down inside the unit.
U can not always see it with your eyes, u must measure it.
Let us hear what u have found

 

[dman636]

well, thats interesting.
After reading this entire forum i do know that there are voltage regulators in the woofer casing. they do control the POD's power aswell.
I also know the cable can be a bit of a problem too (dried out, cracks or bent to long in a strange angle)
perhaps the speakers u have attached had a higher or lower resistance (Ohm's) than the unit can handle, and some components broke down inside the unit.
U can not always see it with your eyes, u must measure it.
Let us hear what u have found

Thanks Peppie. I am sure the resistance changed, i didn’t even think of that. I ran long speaker wires for the satellites. I will try unllugging every thing as much as possible. As far as the power coming from the sub, would i be able to measure that with a standard volt meter?

 

[Peppie1980]

well, here's where my knowledge kinda ends, and i need to google. sound is a frequentie, and i am not sure u can measure it with a voltmeter.
in this case u will definitely need a multimeter, and measure stuff in the woofer casing and POD i believe.
its too bad this thread is ppretty dead, because there used to be ppl who really know there stuff!

Other than that open up the case and start looking and measuring!

 

[Peppie1980]

today my diodes and R21 - R22 resistors came in, turns out, the diodes were not broken, i measured them on the board, thats why i got a false reading (stupid me) i should have desoldered at least 1 leg. anyway, i replaced the resistors R21 and R22 and the pod works again
but still very loud rumbling noise from the woofer and 1 satelite speaker as soon as i turn on the unit :S

might be an Opamp or a TDA, i dont know. i placed back the old ones, still rumbling.

think i need to take the main board out and check everything.
also strange... i saw some tiny sparkling from C214 around U12... cleaned it with alcohol and will check again. its a capacitor, so i dunno whats going there.

 

[sci666]

Good and bad news... I checked the resistor r11 and r16, one of it was brocken. After fixing it the voltage is OK at 8v! Yey! Bad news since I put everything together again, my center speaker is dead! Have anybody an idea what I can check? I changed already the pod no, effect so it must be something with the sub electronics....

 

[Peppie1980]

god, that sucks so hard. whenever u did something. something else brakes down :|
and we have to do it totally from the beginning without any experience, lol.
it is fun though, i have to admit. really frustrating!
but i just cant let this unit sit there, knowing it can be fixed!

where is R16 anyway ??

 

[sci666]

Hey. R16 is nearby the regulator, under the black isolating tape. And I found the error for the center speaker! It seems that I ripped off an smd capacitor in the upper corner by inserting the pcb into the cooler plate. I resoldered the broken joint and it worked!