Hi, have had this for a while but have never tried it
Anyway - replaced all fuses (3 were blown) just to test. On fuse on the back and 2 on the pcb.
Connected a DMM on each loudspeaker terminal and fired up.
Left channel showd 72Vdc - Right channel ~100mV.
After some seconds a bit of smoke appeared somewhere on the board.
It is late here now and bed time... I will take some pictures on a later occasion.
Any initial typical faults that I could be aware of? Blown transistors maybe?
Looks as one or two resistors are blown but I guess it is a reason why that has happened?
I know this is not much to go after....
Some pictures.
First is a overview of the amp.
Second is the area which I saw smoke. However I cannot visually see a problem there.
Third I noticed afterwards that what seems as a cap or resistor has been toast.
I will take everything apart on a later occation.
CJ wasalso kind enough providing me with schematic.
CJ MF2500 fault - smoke
CJ MF2500 fault - smoke
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Re: CJ MF2500 fault - smoke
A loose fuse holder (only soldered at one end to pcb) Q12 (mpsu60l), Q23(nsdu57) and R12 (100r) minimun are broken on left channel. Waiting for some equipment so I can du some more digging..
Probably more that is broken.
Probably more that is broken.
Re: CJ MF2500 fault - smoke
Only one pair of output transistors were gone.
1 2sc3282 and 1 2sa1302..
Anyone know where to get a couple of genuine Toshibas?
1 2sc3282 and 1 2sa1302..
Anyone know where to get a couple of genuine Toshibas?
Re: CJ MF2500 fault - smoke
Q13 (small signal) mje340 on the left channel was also gone.
CJ has stopped responding. Anyone know where to get a service manual?
After it is finished I will chech bias dc offset and so on.
Also did a recap of the psu and changed one fuseholder there.
Sincerely
CJ has stopped responding. Anyone know where to get a service manual?
After it is finished I will chech bias dc offset and so on.
Also did a recap of the psu and changed one fuseholder there.
Sincerely
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Re: CJ MF2500 fault - smoke
Hi everyone,
Does anyone has a schematic on a MF2500 would you please share. The 2 fuses in the picture keep blowing as soon as I turn the switch on. Thank you so much
Does anyone has a schematic on a MF2500 would you please share. The 2 fuses in the picture keep blowing as soon as I turn the switch on. Thank you so much
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Re: CJ MF2500 fault - smoke
I do believe we have this schematic in the database.
-admin
Home Theater in Member Gallery
Main stereo: ART Amplifier and ET7s2. 2nd stereo: PV-14L and MV-55. Previously Owned: PF2 preamp, Evolution 2000 Amp, PV-12AL preamp, D/A-2b Vacuum-Tube Digital Processor.
Home Theater in Member Gallery
Main stereo: ART Amplifier and ET7s2. 2nd stereo: PV-14L and MV-55. Previously Owned: PF2 preamp, Evolution 2000 Amp, PV-12AL preamp, D/A-2b Vacuum-Tube Digital Processor.
Re: CJ MF2500 fault - smoke
I just checked my files and found this. I hope this is what you need.
Happy listening!
Bobby.
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ML CLX BF-210 Stage X Motion 4. CJ 120SE amp ET7V2 pre, Holo May Kte Dac. Mac Pro. Power Cond. BPT Signature+ 3.5, Gaia II Feet. USB Lush^V3. Nordost SPM IC and Spk. Shun Mook, BCanto CD2 CD3. Linn LP-12/Unitrack tonearm/Denon DL103R MC.