BA-5000 with Issues

There are the big fuses you can see in the pic plus 2 on the buffer amp and three on F-2519 the power supply board.
 
A shorted output loads down the power supply enough to prevent the softstart relay from by-passing the ballast resistors.. So the ballast resistors just sit there and cook. This will drastically reduce your raw DC B+/- .
 
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Well in circuit those two 4.7ohm resistors you see inside the yellowish cover both read .7 ohms.
I may have shorted outputs but I would expect to see the power led come on along with the meters.
Right now on power up I get nothing. Its as if a fuse is blown.
 
Well in circuit those two 4.7ohm resistors you see inside the yellowish cover both read .7 ohms.
I may have shorted outputs but I would expect to see the power led come on along with the meters.
Right now on power up I get nothing. Its as if a fuse is blown.
Not if the softstart relay hasn't "set" and by-passed the ballast resistors.
 
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Someone that is not familiar with the SS circuit can easily get pointed erroneously toward a bad power transformer.It bit me in the ass a long time ago on a Marantz 2385.
 
The BA has a "softstart circuit doesn't it ? You may have and shorted output transistor. Check the present resistance of those ballast resistors . R01* and R02* they may look like that cement block resistor close to the fuse in your photo. According to the manual 39Ω 7 watt.


Edited.. My bad.. I was looking at the 3000. For the 5000 the ballast resistors are
R733 and 734 3.9Ω @ 10 watt
 
Looking at the service manual it shows those two resistors in the same location as the relay. I don't see them.
 
Question... When you flip the power switch do you hear that relay "click" almost instantly ?
 
No relay click. There has been a lot of stuff done but the unit was working until I brought it home.
 
Hmm,well I pulled the relay block thinking they were under it. But nothing. I must be losing it.
 
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