Yamaha CR-400

I just purchased a Yamaha CR-400, as-is, that does not turn on. There wasn't a fuse in the back, so I installed a 2.0 amp fuse. The three internal fuses are good.

First let me say that I'm not an electrician or a tech, and don't know all of the correct names and terms, but I have figured things out before. So, I guess that I'm a techs worst nightmare.

Anyway, I'm guessing that the power supply, part # GA60604, is bad. Current is flowing to the transformer, but I'm not getting any power from it.

Using a little AAA battery continuous tester shows that the power switch is good.

Any ideas what else I should check or where I can buy a new power transformer? Or what power transformer from another Yamaha CR receiver would work in it's place?

Whoever worked on this before is worse at soldering them I am.
 

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Yay, thinking that I might have this figured out. Didn't see the fourth internal fuse, it was blown. Replacing that fuse and I got power. But turned unit off the back on, blew the fuse again.

Looking at the solder job on the board it looks like two wires are touching. Out of time, but I plan on resoldering the power transformer wires when I get the time next weekend.
 
I just purchased a Yamaha CR-400, as-is, that does not turn on. There wasn't a fuse in the back, so I installed a 2.0 amp fuse. The three internal fuses are good.

First let me say that I'm not an electrician or a tech, and don't know all of the correct names and terms, but I have figured things out before. So, I guess that I'm a techs worst nightmare.

Anyway, I'm guessing that the power supply, part # GA60604, is bad. Current is flowing to the transformer, but I'm not getting any power from it.

Using a little AAA battery continuous tester shows that the power switch is good.

Any ideas what else I should check or where I can buy a new power transformer? Or what power transformer from another Yamaha CR receiver would work in it's place?

Whoever worked on this before is worse at soldering them I am.
Current is flowing to the transformer, but I'm not getting any power from it.
Do either of the two red LED's illuminate? All four of the incandescent lamps are probably burnt out.Thats not uncommon.
Theres a pigtailed fuse in series with the back panel fuse. Check it with a meter and see if its still good.
There are a couple 4Ω 300ma fusible resistors that might be shot. One is for the regulated power supply and the other is for lamps. FR701 and 702.
 
Thanks. The pigtailed fuse was blown. Replaced it, the unit turned on, had sound from the speakers, then the good old burning smell and the fuse blew again. Can't work on it again until next weekend.
 
Thanks. The pigtailed fuse was blown. Replaced it, the unit turned on, had sound from the speakers, then the good old burning smell and the fuse blew again. Can't work on it again until next weekend.
Hi Truckrglenn, I have the same problem with a CR-400, turned on, good sound and then the pigtail fuse blew again. What did you find in yours?
 
Hi Truckrglenn, I have the same problem with a CR-400, turned on, good sound and then the pigtail fuse blew again. What did you find in yours?
What size is the primary fuse on the rear panel?

What is your mains voltage Rafael?
 
What size is the primary fuse on the rear panel?

What is your mains voltage Rafael?
The primary fues is 2A, 250V and internally has another 2A welded to it. If you are referring to my power voltage to de receiver it is 115V. Thanks for looking into my problem. I just measured all the resistors in the Main power board and found that R603 and R604 are 11K Ohms instead of the 220K as called in the schematic. I haven't check the values vs color codes yet. Experiences and suggestions are very welcome
 
Check R638 and 640 emitter resistors as well ( .47Ω / 2watt)
 
Pull and check the right channel output transistors.TR616 and 618.
Pulled up TR618, + on Base (pin 1) and - on emitter (pin 3) = 1.4k Ohms, +E and -B = 2.1k Ohms. +B and -C = 1.4K Ohms, +C and -B = 2.1k Ohms, Collector and Emitter no resistance both ways. I have not pulled TR616 but when I measured it in circuit it doesn't present faulty values which are similar to what I measured in TR615 in circuit. R638 and R640 measured OK
 
Pulled up TR618, + on Base (pin 1) and - on emitter (pin 3) = 1.4k Ohms, +E and -B = 2.1k Ohms. +B and -C = 1.4K Ohms, +C and -B = 2.1k Ohms, Collector and Emitter no resistance both ways. I have not pulled TR616 but when I measured it in circuit it doesn't present faulty values which are similar to what I measured in TR615 in circuit. R638 and R640 measured OK
That looks bad to me.
 
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