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9090 receiver in protection

i order from Digikey nice and fast ,changed out the blueish resistors ,before i put board in back in what way dose it go ? resistors to the front of the receiver that how it was in ? ,
thanks
 
I just fixed the same problem on my 7070. It didnt come out of protection until I replaced all fuse resistors on the mother board too. fwiw
 
On a 9090 the board can go in either way but it's best to put the component side facing outwards (towards the center of the receiver) for better cooling.

- Pete
 
i put board F2436-1 in (towards the center of the receiver) still in protection and no right Chanel haven't checked to see if light out ? haven't checked fuse resistors on the mother board what the number of at board ?
 
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The 9090 does not have the same setup as my 7070. I took a quick peek at the 9090 service manual and didnt see any fuse resistors on the 2547 protector board or the 2546 power supply board. Sorry, I'm no help to you on this.
 
The 9090 and 7070 have completely different amplifier sections. The 7070 is similar in design to the 9090DB.

Jobrated, I'm confused. If it's in protection, neither channel should have sound.

- Pete
 
yes your right .. it's still in protection neither channel have sound . i put board F2436-1 in (towards the center of the receiver) as you said not sure what to check next.

thanks
 
You may have a problem on the protection board itself. Check all the transistors on the board (4 of them, I think). If they are good, then recap the protection board. I run into a problem with protection fairly often. Usually a recap will fix it. It's just not worth the time to try and figure out which cap is bad, for just a couple dollars, change 'em all. Only once, at our shop, have transistors been bad on the protection board. Practically always, it's old caps.

The protection board works by averaging voltages over time and it uses caps to do this.
 
Looking at your picture of the driver board again, it seems there is a resistor missing, the one in the vinyl sleeve that is on the left side but missing on the right. This board is completely symetrical so should have same components left and right, in a mirror image configuration.
 
that was the fuse with vinyl sleeve i had it out when i took photo . looks like there 4 cap on board two black to blue in photo
 

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I don't mean the caps on that board, although it would be a good idea to change them out. I am talking about the protection board, changing those caps.
 
There is still something farked on the driver board, most likely. You need to check the transistors. Do you know how? Have you checked the outputs?

Also, check all of your work....make sure you put the correct value resistors in their correct locations..
 
And you can also check the outputs of both channels. Maybe they are putting out some voltage, and the protection is working properly. If that were the case, pulling the driver board would take it out of protection. Doesn't mean much really, I think pulling the board would always get one of these out of protection.

Look on the schematic and see where, or maybe just measure the voltage at the protection relay. I'm not sure of the spec but most anything DC over about 1/2 a volt might trip the protection.

If you've got less than a few hundred mv, the protection should not kick in. You can set the offset with it in protection, and if you can get it down to speck (within + or - 10mv) then you would know there was a problem in the protection. But you gotta measure it.
 
some of the resistors have the "S" bends in the legs and or they stand up off the circuit board . the one i replace are smaller and i didn't put them back like that and there down on the board now will this work ???
 
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