Yamaha RX-V800 Won't Turn On

S

sansuilove

Active Member

• Dec 9, 2014

• #1

Hello friends...
I have this receiver that is doing me a big problems..
it refuses to turn on. I click the button,a small relay sound click but nothing - no screen..no audio no turn on..
I also notice that when I push the power button,the light in my room flickers.
Made checks and found out this :

C301/303 - 24.3AC
D301 - shows 11.06v both ways
Q301 collector - 11.06 .


:sigh:

 

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Last edited: Dec 11, 2014

petehall347

the brandy coffee man

• Dec 9, 2014

• #2

24.3v concerns me .looks like the line voltage is nearly double what it should be .

 

S

sansuilove

Active Member

• Dec 9, 2014

• #3

yes me too.. what is feeding the Q301 with 11.06V?
made some reading and few people talked about a .22uf 275v capacitor that tends to fail also.
thank you Petehall

 

Last edited: Dec 10, 2014

petehall347

the brandy coffee man

• Dec 10, 2014

• #4

what i was getting at is it could be a 120v unit running on 240v

 

S

sansuilove

Active Member

• Dec 10, 2014

• #5

Oh no it's a multivoltage unit and i made sure it's set on 220V (belgium)
I invistigated further more and found out that 3 output transistors are shorted in everyway..
could be that this is the cause of the problem?
im ordering new ones at this moment.

 

Last edited: Dec 11, 2014

petehall347

the brandy coffee man

• Dec 10, 2014

• #6

maybe voltage is high because of no current draw .
voltages are wrong at d301 because A q301 base is low voltage .. check it .. its highly likely the blown outputs are causing q301 to not turn and ground ry301

 

S

sansuilove

Active Member

• Dec 10, 2014

• #7

I understand..ummm...
I wished to ask you also Pete,what components would you suggest checking that could be also damaged along with the output transistors?

 

S

sansuilove

Active Member

• Dec 11, 2014

• #8

Ok i went on and I made checks on the route of the output transistors - all good.
I turned on the unit and Voilà ! turned ON all good , of course no sound yet from the channel missing transistors . I hope they will arrive soon and I can give it back to my friend.
MERCI Pete.

 

S

sansuilove

Active Member

• Jan 3, 2015

• #9

I hate when this happens receiver worked great for 3 days and then the same problem again.. I tested all output transistors and all is O.K.

I'm trying to determine whether the problem is in the power supply board or amplifier board , and would love some help to "take the amp board out of circuit"
disconnecting the B+/B- ?

 

S

sansuilove

Active Member

• Mar 3, 2015

• #10

I took the amplifier board out of circuit and tried to fire her up - nothing. seems like the turn on/off switch is related to that board . is there a way I can turn it on ?