Blowing fuses.......

[Ultracrazy]

I have a RX-V393 Yamaha receiver that won't turn on........and yes.....it's pluged in I can hear it click like it want's to spark up.......but no dice.
I have opened it up and replaced the fuse that keeps blowing. I think this unit is about 10 years old.........is it dead? Should I just man up and get a new one?
UC

[Cheap Thrills]

If it hums a second and then blows the fuse or blows the fuse instantly upon power up , chances are that the rectifier diodes are shot. Generally it's an easy fix but what caused the diodes to short may be another story. could have been just a power line voltage surge like what happens when the power flashes during a storm. If that's the case then it should be fairly simple and inexpensive.
On the other hand there are several other components that could cause the rectifier to go out like a faulty regulator, also an easy fix but if the regulator surged the output transistors on it's way out then the repair could get costly.
if you open up the case look close to where the power fuse is there should be 5 +/ - round black diodes with a white or silver stripe on the end. ( Just one end ) Sometimes if they suffer a violent death they will either exibit signs of their demise such as a burnt smell, char around the circut board and sometimes even cracks or pieces blown out. but not always. If you're going to attempt replacing them yourself be damn sure to note which way the stripes are pointed one wrong placement and you will fry them again or worse fry something that wasn't fried before.
Oh yeah, Unplugging it first would be a good idea also :rollside:
BTW you can check the diodes with a multimeter for continuity they should pass current one way but not the other. you may have to pull one leg of the diode up out of the circut to check it.
Unplug it first
Dont ask me why I keep telling you to unplug it :220v: if you forget and it bites you , chances are that burning smell you smell is yer noodle cookin.
C.T. :wink:

[Cheap Thrills]

OOps my bad the it looks like the rectifiers are intergrated on that unit . looking at the schematic here it shows two ICs rectifiers. board designator numbers are D 111 and D 314-317 . Wait this schematic reads like japanese stereo instructions
In one diagram it shows them as a group of single diodes and in another view it's showing them as intergrated. without having it here I couldn't say what it has.
But anyhow I would bet the rectifier diodes are your problem.
" Diode check, Take three" * Click
bottom of Page 6 on the schem. + - LB Powersupply diodes show designator location numbers D314,D315,D316 and D317 as single diodes.
Here's the schematic if you want it. RX-v393 (http://www.epanorama.net/schematics....tic%20Only.pdf)
C.T. :wink:

[Cheap Thrills]

Ha hahaha On another note if the amp fires up and goes through the self diagnostics and then blows the fuse when the output relays engage, the output transistors may be at fault.
Replacing the output transistors could get costly depending on what caused them to go.
Solid state stuff tends to go through a domino effect when circuts fail.
But sometimes you get lucky and just have to replace a component or two.
Good Luck with it Let me know what you find if you dig into it.
C.T. :wink:

[Ultracrazy]

First of all you lost me at "if it.........."
Second of all........what it does is as soon as you push the on button it clicks like its going to turn on.......but nothing. When I opened it up........when I clicked in on, the fuse would vibrate.......but nothing. When I pushed again in would just blow.
So.........I'll try to print out the "plans" and try to identify anything that looks familiar. And..........nothing else looks like it has been fried.
Thanks for taking the time to answer my thread.
Steve

[ROZ]

The repair will likely cost half the cost of the replacement unit, if you send it out for repair. My advise is to get the new version. It's better, too
I'm getting the RXV659 for my pops for his birthday. retail is 500.00. I'm getting it for 384.00 through a buddy... Pretty good deal. I think it has 2zones, too

[Ultracrazy]

The repair will likely cost half the cost of the replacement unit, if you send it out for repair. My advise is to get the new version. It's better, too
I'm getting the RXV659 for my pops for his birthday. retail is 500.00. I'm getting it for 384.00 through a buddy... Pretty good deal. I think it has 2zones, too
What is a zone?........all I need is something to run my speakers in that are intergrated in the house. I have a home theater system already.

[Beer-30]

'Bout a month ago, my 3 year old Harman Kardon AVR-525 clicked off. I was watching a movie and it just shut off. I got off the couch and turned it back on. It stayed on for 3-4 seconds and shut off.
I reset the whole receiver back to default, unplugged it for a half hour or so, and turned it back on. About 5 minutes later, it shut off.
I unplugged everything and set it on the kitchen counter. Turned it on and timed it, so I could tell the repair center how long it takes. Well, it never turned off. Now I looked to my wiring.
I got the multi-meter out and started with the speakers. OHMs: LF- 3.93, RF-3.90, Center-7.4, LR-1.3, RR-3.95.
So, I start looking at the wires where they connect to the wall. I put a set of wall plates in the wall so there are gold terminals to connect to instead of wires haging out. Well, one of the top trim plate screws had vibrated out and fell on the LR terminals. Right between the + and -, making a connection. Apparently that made the amp go into safe mode and shut down the whole receiver. Removed the screw and all it fine.

[Beer-30]

What is a zone?........all I need is something to run my speakers in that are intergrated in the house. I have a home theater system already.
On a 7.1 channel receiver, one can usually assign the #6 and #7 channels to another ZONE. Like the patio. Or garage. Then, you have separate control over that ZONE. You can watch a 5.1 movie in the liv room while you have the radio or cd on in the other zone. Or play the movie on all zones. Etc. It's like two receivers in one.

[Ultracrazy]

'Bout a month ago, my 3 year old Harman Kardon AVR-525 clicked off. I was watching a movie and it just shut off. I got off the couch and turned it back on. It stayed on for 3-4 seconds and shut off.
I reset the whole receiver back to default, unplugged it for a half hour or so, and turned it back on. About 5 minutes later, it shut off.
I unplugged everything and set it on the kitchen counter. Turned it on and timed it, so I could tell the repair center how long it takes. Well, it never turned off. Now I looked to my wiring.
I got the multi-meter out and started with the speakers. OHMs: LF- 3.93, RF-3.90, Center-7.4, LR-1.3, RR-3.95.
So, I start looking at the wires where they connect to the wall. I put a set of wall plates in the wall so there are gold terminals to connect to instead of wires haging out. Well, one of the top trim plate screws had vibrated out and fell on the LR terminals. Right between the + and -, making a connection. Apparently that made the amp go into safe mode and shut down the whole receiver. Removed the screw and all it fine.
I unhooked the reciever and placed it in on the counter and plugged it back in.............same result......it wouldn't even fire up.