sx 1250 Stabilizer voltage issue

sendust

Music feeds the soul
Hi guys, i picked up a sx 1250 a while back and it had issues on right channel, it would cut out frequently. I cleaned all connections and pots, also worked switches well, no change. I decided to recap the unit . since recapping right channel is working well. after recap i reset the two power amplifiers VR1to 0 and VR2 to 65 mv, while trying to set stabilizer i was able to set VR1 to 65 mv but on VR2 i was only able to set to - 48 , any thought son this.
 
Is the Stabiliser original or has it been rebuilt?

I had some similar problems with one during a rebuild last week....

It should also be +65 and -65VDC not mV, if it is mV you have some real issues..
 
Is the Stabiliser original or has it been rebuilt?

I had some similar problems with one during a rebuild last week....

It should also be +65 and -65VDC not mV, if it is mV you have some real issues..
Sorry it is VDC, the caps have been replaced nothing else
 
It sounds like this might have been the problem all along, if these voltages are off, the unit will go into protection.

Search SX1250 BOM and compile a list to completely rebuild the stabiliser.
Just replacing caps in these amps is not enough these days, especially that particular board.
You need to replace all the transistors, diodes, and Zeners, I also replaced some of the resistors as well, three I think, the most stressed ones, and of course the two trimmers
Once you have done this you'll be set and good to go. If there is an issue after that, I will know exactly what the problem will be.
 
It sounds like this might have been the problem all along, if these voltages are off, the unit will go into protection.

Search SX1250 BOM and compile a list to completely rebuild the stabiliser.
Just replacing caps in these amps is not enough these days, especially that particular board.
You need to replace all the transistors, diodes, and Zeners, I also replaced some of the resistors as well, three I think, the most stressed ones, and of course the two trimmers
Once you have done this you'll be set and good to go. If there is an issue after that, I will know exactly what the problem will be.
thanks will do
 
It sounds like this might have been the problem all along, if these voltages are off, the unit will go into protection.

Search SX1250 BOM and compile a list to completely rebuild the stabiliser.
Just replacing caps in these amps is not enough these days, especially that particular board.
You need to replace all the transistors, diodes, and Zeners, I also replaced some of the resistors as well, three I think, the most stressed ones, and of course the two trimmers
Once you have done this you'll be set and good to go. If there is an issue after that, I will know exactly what the problem will be.
The list i see is power supply stabilizer, is this correct? and is this list mouser or digikey
 
The list i see is power supply stabilizer, is this correct? and is this list mouser or digikey
I think its the AWR106....the BOM's are Mouser.

I had a thread up the other day when I was working on the one I have here but I cant find it at the moment...
 
I had a thread up the other day when I was working on the one I have here but I cant find it at the moment...

From MTF's post, cira 2013.

  1. Ok, here's a raw updated list, with ALMOST EVERYTHING POSSIBLE - you WILL NOT need all this. Every correction and stock check I can do and think of has been done.

    I'm trying something different, making it easier to get this into a spreadsheet.
    I am posting it as a comma delimited text block, where the commas are the field delimiters. a .csv file - in text...

    DO NOT BLINDLY COPY AND PASTE THE PARTS LIST, YOU WILL OVERSPEND BY AT LEAST TWO EXTRA RELAYS ($20) AND SOME OTHER STUFF.

    sx-1250,power,supply,stabilizer,ok,,,,,
    sx-1250,awr-106,c1,220,80,cea,,220,100,647-UPW2A221MHD
    sx-1250,awr-106,c2,220,80,cea,,220,100,647-UPW2A221MHD
    sx-1250,awr-106,C5,47,35,cea,,47,35,647-UPW1V470MED
    sx-1250,awr-106,C6,47,35,cea,,47,35,647-UPW1V470MED
    sx-1250,awr-106,C7,22,50,cea,,22,50,647-UPW1H220MDD
    sx-1250,awr-106,C8,22,50,cea,,22,50,647-UPW1H220MDD
    sx-1250,awr-106,C9,100,35,cea,,100,50,647-UPW1H101MPD
    sx-1250,awr-106,C10,100,35,cea,,100,50,647-UPW1H101MPD
    sx-1250,awr-106,C11,47,80,cea,,47,100,647-UPW2A470MPD
    sx-1250,awr-106,C12,47,80,cea,,47,100,647-UPW2A470MPD
    sx-1250,awr-106,C13,1000,25,ceb,,1000,35,647-TVX1V102MCD
    sx-1250,awr-106,C15,47,10,cea,,47,10,647-UPW1A470MDD6
    sx-1250,awr-106,C16,22,10,cea,,22,10,647-UPW1A220MDD
    sx-1250,awr-106,C17,220,16,cea,,220,25,647-UPW1E221MPD1TD
    sx-1250,awr-106,C18,47,10,cea,,47,10,647-UPW1A470MDD6
    sx-1250,awr-106,C19,47,10,cea,,47,10,647-UPW1A470MDD6
    sx-1250,awr-106,q1,2sd313,pass +65,,,,,512-KSC2073TU
    sx-1250,awr-106,q2,2sc869,darl,,,,,512-KSC2383YTA
    sx-1250,awr-106,q3,2sc1318,err-amp,,,,,512-KSC1845FTA
    sx-1250,awr-106,q4,2sc1384,pass +25,,,,,512-KSC2690AYS
    sx-1250,awr-106,q5,2sb507,pass -65,,,,,512-KSA940TU
    sx-1250,awr-106,q6,2sa628,darl,,,,,512-KSA1013YBU
    sx-1250,awr-106,q7,2sa720,err-amp,,,,,512-KSA992FBU
    sx-1250,awr-106,q8,2sa684,pass -25,,,,,512-KSA1220AYS
    sx-1250,awr-106,q9,2sd325,pass +13,,,,,512-KSC2073TU
    sx-1250,awr-106,q10,2sc945,darl,,,,,512-KSC2383YTA
    sx-1250,awr-106,q11,2sc945,err-amp,,,,,512-KSC1845FTA
    sx-1250,awr-106,q12,2sd325,pass +5.5 ,,,,,512-KSC2073TU
    sx-1250,awr-106,q13,2sc945,darl,,,,,512-KSC2383YTA
    sx-1250,awr-106,d1,wz-240,,,,,,512-1N5252B
    sx-1250,awr-106,d3,wz-240,,,,,,512-1N5252B
    sx-1250,awr-106,d5,wz-061,,,,,,512-1N5234B
    sx-1250,awr-106,d2,1s2473,,,,,,512-1n4148
    sx-1250,awr-106,d4,1s2473,,,,,,512-1n4148
    sx-1250,awr-106,vr1,4.7k,1 turn,,,,,652-3386H-1-502LF
    sx-1250,awr-106,vr2,4.7k,1 turn,,,,,652-3386H-1-502LF
    sx-1250,awr-106,R13,680,2W mox,,,,,660-MO2C681J
    sx-1250,awr-106,R14,1.5K,2W mox,,,,,660-MO2C152J
    sx-1250,awr-106,R18,100,2W mox,,,,,660-MO2C101J
    ,,,,,,,,,
    ,,,,,,,,,
    ,,,,,,,,,
    sx-1250,power,amp,left,ok,,,,,
    sx-1250,awh-048l,C2,10,16,ceanl,,10,50,647-UKL1H100KDDANA
    sx-1250,awh-048l,C5,220,16,ceanl,,220,16,647-UKL1C221KPDANA
    sx-1250,awh-048l,C11,0.22,10,csza,,0.22,50,667-ECQ-V1H224JL
    sx-1250,awh-048l,C15,470,80,ACH-038,,470,100,647-UPW2A471MHD
    sx-1250,awh-048l,C16,470,80,ACH-038,,470,100,647-UPW2A471MHD
    sx-1250,awh-048l,q1,2sa750,,,,,,512-KSA992FBU
    sx-1250,awh-048l,q2,2sa750,,,,,,512-KSA992FBU
    sx-1250,awh-048l,q3,2sc1439,,,,,,512-KSC3503dstu
    sx-1250,awh-048l,q4,2sc1439,,,,,,512-KSC3503dstu
    sx-1250,awh-048l,q5,2sa858,,,,,,512-KSA1381ESTU
    sx-1250,awh-048l,q6,2sa858,,,,,,512-KSA1381ESTU
    sx-1250,awh-048l,q7,2sc1904,,,,,,512-KSC3503dstu
    sx-1250,awh-048l,q8,2sa899,,,,,,512-KSA1381ESTU
    sx-1250,awh-048l,q9,2sd610,,,,,,512-KSC2073TU
    sx-1250,awh-048l,q10,2sb630,,,,,,512-KSA940TU
    sx-1250,awh-048l,q11,2sc869,,,,,,512-KSC1845FTA
    sx-1250,awh-048l,vr1,500 ohms,offset,25 turns,,,,652-3296P-1-501LF
    sx-1250,awh-048l,vr2,500 ohms,idle,1 turn,,,,652-3386H-1-501LF
    ,,,,,,,,,
    ,,,,,,,,,
    ,,,,,,,,,
    sx-1250,power,amp,right,ok,,,,,
    sx-1250,awh-048r,C2,10,16,ceanl,,10,50,647-UKL1H100KDDANA
    sx-1250,awh-048r,C5,220,16,ceanl,,220,16,647-UKL1C221KPDANA
    sx-1250,awh-048r,C11,0.22,10,csza,,0.22,50,667-ECQ-V1H224JL
    sx-1250,awh-048r,C15,470,80,ACH-038,,470,100,647-UPW2A471MHD
    sx-1250,awh-048r,C16,470,80,ACH-038,,470,100,647-UPW2A471MHD
    sx-1250,awh-048r,q1,2sa750,,,,,,512-KSA992FBU
    sx-1250,awh-048r,q2,2sa750,,,,,,512-KSA992FBU
    sx-1250,awh-048r,q3,2sc1439,,,,,,512-KSC3503dstu
    sx-1250,awh-048r,q4,2sc1439,,,,,,512-KSC3503dstu
    sx-1250,awh-048r,q5,2sa858,,,,,,512-KSA1381ESTU
    sx-1250,awh-048r,q6,2sa858,,,,,,512-KSA1381ESTU
    sx-1250,awh-048r,q7,2sc1904,,,,,,512-KSC3503dstu
    sx-1250,awh-048r,q8,2sa899,,,,,,512-KSA1381ESTU
    sx-1250,awh-048r,q9,2sd610,,,,,,512-KSC2073TU
    sx-1250,awh-048r,q10,2sb630,,,,,,512-KSA940TU
    sx-1250,awh-048l,q11,2sc869,,,,,,512-KSC1845FTA
    sx-1250,awh-048r,vr1,500 ohms,offset,25 turns,,,,652-3296P-1-501LF
    sx-1250,awh-048r,vr2,500 ohms,idle,1 turn,,,,652-3386H-1-501LF
    ,,,,,,,,,
    ,,,,,,,,,
    ,,,,,,,,,
    ,,,,,,,,,
    ,,,,,,,,,
    sx-1250,protection,ok,,,,,,,
    sx-1250,awm-091,C1,470,6,cea,,470,10,647-UPW1C471MPD6
    sx-1250,awm-091,C2,470,6,cea,,470,10,647-UPW1C471MPD6
    sx-1250,awm-091,C3,4.7,25,cea,,4.7,50,647-UPW1H4R7MDD
    sx-1250,awm-091,C4,100,16,cea,,100,16,647-UPW1C101MED
    sx-1250,awm-091,C5,100,50,cea,,100,50,647-UPW1H101MPD
    sx-1250,awm-091,C6,100,50,cea,,100,50,647-UPW1H101MPD
    sx-1250,awm-091,q1,2sc945,,diff,,,,512-KSC1845FTA
    sx-1250,awm-091,q2,2sc945,,diff,,,,512-KSC1845FTA
    sx-1250,awm-091,q3,2sa733,,or logic,,,,512-KSA992FBU
    sx-1250,awm-091,q4,2sc945,,current dump,,,,512-KSC2383YTA
    sx-1250,awm-091,q5,2sc1166,,relay drive,,,,512-KSC2690AYS
    sx-1250,awm-091,q6,2sc1166,,v reg,,,,512-KSC2690AYS
    sx-1250,awm-091,s1,asr-010,prot relay,,,,,653-my4-02dc24
 
continued from last post

,,,,,,,,,
sx-1250,tuner,ok,,,,,,,
sx-1250,awe-068,C4,220,16,cea,,220,16,647-UPW1C221MPD
sx-1250,awe-068,C10,0.47,50,cea,,0.47,50,667-ECQ-V1H474JL
sx-1250,awe-068,C23,10,16,csza,,10,50,647-UKL1H100KDDANA
sx-1250,awe-068,C24,47,16,ceanl,,47,25,647-UKL1V470MPDANA
sx-1250,awe-068,C25,470,16,cea,,470,25,647-UPW1E471MPD
sx-1250,awe-068,C26,4.7,25,ceanl,,4.7,25,647-UKL1E4R7KDDANA
sx-1250,awe-068,C28,10,16,csza,,10,50,647-UKL1H100KDDANA
sx-1250,awe-068,C29,10,16,csza,,10,50,647-UKL1H100KDDANA
sx-1250,awe-068,C32,100,16,cea,,100,16,647-UPW1C101MED
sx-1250,awe-068,C33,1,50,cea,,1,50,647-UPW1H010MDD
sx-1250,awe-068,C35,0.1,35,csza,,0.1,50,598-DSF050J
sx-1250,awe-068,C36,1,25,ceanl,,1,50,647-UKL1H010KDDANA
sx-1250,awe-068,C38,1,25,ceanl,,1,50,647-UKL1H010KDDANA
sx-1250,awe-068,C41,1,10,csza,,1,50,647-UKL1H010KDDANA
sx-1250,awe-068,C42,3.3,10,csza,,3.3,50,647-UKL1H3R3KDDANA
sx-1250,awe-068,C43,0.22,25,csza,,0.22,50,667-ECQ-V1H224JL
sx-1250,awe-068,C48,4.7,25,ceanl,,4.7,25,647-UKL1E4R7KDDANA
sx-1250,awe-068,C56,10,16,csza,,10,50,647-UKL1H100KDDANA
sx-1250,awe-068,C59,0.1,35,csza,,0.1,50,598-DSF050J
sx-1250,awe-068,C60,220,16,cea,,220,16,647-UPW1C221MPD
sx-1250,awe-068,C61,47,16,ceanl,,47,25,647-UKL1V470MPDANA
,,,,,,,,,
,,,,,,,,,
sx-1250,equalizer,amp,ok,,,,,,
sx-1250,awf-021,C1,1,100,mylar,ecq,,,
sx-1250,awf-021,C2,1,100,mylar,ecq,,,
sx-1250,awf-021,C11,470,6,cea,,470,10,647-UPW1C471MPD6
sx-1250,awf-021,C12,470,6,cea,,470,10,647-UPW1C471MPD6
sx-1250,awf-021,C17,3.3,50,ceanl,,3.3,50,647-UKL1H3R3KDDANA
sx-1250,awf-021,C18,3.3,50,ceanl,,3.3,50,647-UKL1H3R3KDDANA
sx-1250,awf-021,C25,22,16,csza,,22,25,647-UKL1E220MDDANA
sx-1250,awf-021,C26,22,16,csza,,22,25,647-UKL1E220MDDANA
sx-1250,awf-021,C27,220,63,cea,,220,100,647-UPW2A221MHD
sx-1250,awf-021,C28,220,63,cea,,220,100,647-UPW2A221MHD
sx-1250,awf-021,C29,100,35,cea,,100,35,647-UPW1V101MPD
sx-1250,awf-021,C30,22,16,csza,,22,25,647-UKL1E220MDDANA
sx-1250,awf-021,C31,22,16,csza,,22,25,647-UKL1E220MDDANA
sx-1250,awf-021,C32,100,35,cea,,100,35,647-UPW1V101MPD
sx-1250,awf-021,q1,2sa726,ltp-L,,,,,512-KSA992FBU
sx-1250,awf-021,q2,2sa726,ltp-R,,,,,512-KSA992FBU
sx-1250,awf-021,q3,2sa726,ltp-L,,,,,512-KSA992FBU
sx-1250,awf-021,q4,2sa726,ltp-R,,,,,512-KSA992FBU
sx-1250,awf-021,q5,2sc1775,vas-L,,,,,512-KSC1845FTA
sx-1250,awf-021,q6,2sc1775,vas-R,,,,,512-KSC1845FTA
sx-1250,awf-021,q7,2sc1775,out dvr-L,,,,,512-KSC1845FTA
sx-1250,awf-021,q8,2sc1775,out dvr-R,,,,,512-KSC1845FTA
sx-1250,awf-021,q9,2sa872,out dvr-L,,,,,512-KSA992FBU
sx-1250,awf-021,q10,2sa872,out dvr-R,,,,,512-KSA992FBU
sx-1250,awf-021,q11,2sc1735,pass +49,,,,,512-KSC2690AYS
sx-1250,awf-021,q12,2sc869,err amp +,,,,,512-KSC1845FTA
sx-1250,awf-021,q13,2sa850,pass -49,,,,,512-KSA1220AYS
sx-1250,awf-021,q14,2sa628,err amp -,,,,,512-KSA992FBU
sx-1250,awf-021,d5,wz-240,,,,,,512-1N5252B
sx-1250,awf-021,d6,wz-240,,,,,,512-1N5252B
,,,,,,,,,
sx-1250,flat,amp,ok,,,,,,
sx-1250,AWG-042,C7,330,63,cea,,330,63,647-UPW1J331MHD
sx-1250,AWG-042,C8,330,63,cea,,330,63,647-UPW1J331MHD
sx-1250,AWG-042,C9,22,16,csza,,22,25,647-UKL1E220MDDANA
sx-1250,AWG-042,C10,22,16,csza,,22,25,647-UKL1E220MDDANA
sx-1250,AWG-042,C11,22,16,csza,,22,25,647-UKL1E220MDDANA
sx-1250,AWG-042,C12,22,16,csza,,22,25,647-UKL1E220MDDANA
sx-1250,AWG-042,C21,100,10,ceanl,,100,25,647-UKL1E101KPDANA
sx-1250,AWG-042,C22,100,10,ceanl,,100,25,647-UKL1E101KPDANA
sx-1250,AWG-042,C27,220,16,ceanl,,220,16,647-UKL1C221KPDANA
sx-1250,AWG-042,C28,220,16,ceanl,,220,16,647-UKL1C221KPDANA
sx-1250,AWG-042,C31,330,35,cea,,330,50,647-UPW1H331MPD
sx-1250,AWG-042,C32,330,35,cea,,330,50,647-UPW1H331MPD
sx-1250,AWG-042,q1,2sc1775,,,,,,512-KSC1845FTA
sx-1250,AWG-042,q2,2sc1775,,,,,,512-KSC1845FTA
sx-1250,AWG-042,q3,2sa872,,,,,,512-KSA992FBU
sx-1250,AWG-042,q4,2sa872,,,,,,512-KSA992FBU
sx-1250,AWG-042,q5,2sk30,,,,,,
sx-1250,AWG-042,q6,2sk30,,,,,,
sx-1250,AWG-042,q7,2sa725,,,,,,512-KSA992FBU
sx-1250,AWG-042,q8,2sa725,,,,,,512-KSA992FBU
,,,,,,,,,
,,,,,,,,,
,,,,,,,,,
sx-1250,control,amp,ok,,,,,,
sx-1250,AWG-041,C1,4.7,25,csza,,4.7,25,647-UKL1E4R7KDDANA
sx-1250,AWG-041,C2,4.7,25,csza,,4.7,25,647-UKL1E4R7KDDANA
sx-1250,AWG-041,C3,4.7,25,csza,,4.7,25,647-UKL1E4R7KDDANA
sx-1250,AWG-041,C4,4.7,25,csza,,4.7,25,647-UKL1E4R7KDDANA
sx-1250,AWG-041,C11,2.2,25,ceanl,,2.2,50,647-UKL1H2R2MDDANA
sx-1250,AWG-041,C12,2.2,25,ceanl,,2.2,50,647-UKL1H2R2MDDANA
sx-1250,AWG-041,C13,2.2,25,ceanl,,2.2,50,647-UKL1H2R2MDDANA
sx-1250,AWG-041,C14,2.2,25,ceanl,,2.2,50,647-UKL1H2R2MDDANA
sx-1250,AWG-041,C17,100,10,ACH-312,,100,16,647-UPW1C101MED
sx-1250,AWG-041,C18,100,10,ACH-312,,100,16,647-UPW1C101MED
sx-1250,AWG-041,C19,2.2,25,ceanl,,2.2,50,647-UKL1H2R2MDDANA
sx-1250,AWG-041,C20,2.2,25,ceanl,,2.2,50,647-UKL1H2R2MDDANA
sx-1250,AWG-041,C27,2.2,25,ceanl,,2.2,50,647-UKL1H2R2MDDANA
sx-1250,AWG-041,C28,2.2,25,ceanl,,2.2,50,647-UKL1H2R2MDDANA
sx-1250,AWG-041,C29,2.2,25,ceanl,,2.2,50,647-UKL1H2R2MDDANA
sx-1250,AWG-041,C30,2.2,25,ceanl,,2.2,50,647-UKL1H2R2MDDANA
sx-1250,AWG-041,C33,100,10,ACH-312,,100,16,647-UPW1C101MED
sx-1250,AWG-041,C34,100,10,ACH-312,,100,16,647-UPW1C101MED
sx-1250,AWG-041,C35,2.2,25,ceanl,,2.2,50,647-UKL1H2R2MDDANA
sx-1250,AWG-041,C36,2.2,25,ceanl,,2.2,50,647-UKL1H2R2MDDANA
sx-1250,AWG-041,C37,100,16,ACH-311,,100,16,647-UPW1C101MED
sx-1250,AWG-041,C38,100,16,ACH-311,,100,16,647-UPW1C101MED
sx-1250,AWG-041,C39,100,16,ACH-311,,100,16,647-UPW1C101MED
sx-1250,AWG-041,C40,100,16,ACH-311,,100,16,647-UPW1C101MED
sx-1250,AWG-041,C43,10,25,csza,,10,50,647-UKL1H100KDDANA
sx-1250,AWG-041,C44,10,25,csza,,10,50,647-UKL1H100KDDANA
sx-1250,AWG-041,q1,2sc1312,,,,,,512-KSC1845FTA
sx-1250,AWG-041,q2,2sc1312,,,,,,512-KSC1845FTA
sx-1250,AWG-041,q3,2sc1312,,,,,,512-KSC1845FTA
sx-1250,AWG-041,q4,2sc1312,,,,,,512-KSC1845FTA
,,,,,,,,,
,,,,,,,,,
sx-1250,filter,amp,ok,,,,,,
sx-1250,AWM-089,C3,4.7,25,csza,,4.7,25,647-UKL1E4R7KDDANA
sx-1250,AWM-089,C6,10,25,csza,,10,50,647-UKL1H100KDDANA
sx-1250,AWM-089,c9,4.7,25,csza,,4.7,25,647-UKL1E4R7KDDANA
sx-1250,AWM-089,c12,10,25,csza,,10,50,647-UKL1H100KDDANA
sx-1250,AWM-089,q1,2sc1313,,,,,,512-KSC1845FTA
sx-1250,AWM-089,q2,2sc1313,,,,,,512-KSC1845FTA
,,,,,,,,,
,,,,,,,,,
sx-1250,fused,power,ok,,,,,,
sx-1250,AWR-107,C6,470,100,ceb,,470,100,647-TVX2A471MCD
sx-1250,AWR-107,C7,470,100,ceb,,470,100,647-TVX2A471MCD
sx-1250,AWR-107,C8,470,25,cea,,470,25,647-UPW1E471MPD
sx-1250,AWR-107,C9,470,25,cea,,470,25,647-UPW1E471MPD
,,,,,,,,,
,,,,,,,,,
sx-1250,chassis,s2,asr-015,soft start,relay,pcb mt,pins,,653-LY2-0-DC48
sx-1250,chassis,s2,asr-015,soft start,relay,NO mount,tabs,,653-LY2-DC48
,,,,,,,,,
sx-1250,chassis,s2,asr-015,soft start,relay,ears mount,tabs,,653-ly1f-dc48
sx-1250,chassis,,,soft start,ly1f mount,m-f standoff,,,728-FM2110-3005-SS | 2
sx-1250,chassis,,,soft start,ly1f mount,f-f standoff,,,728-FM1262-3005-SS | 2
,,,,,,,,,
,,,,,,,,,
sx-1250,function ,switch,assy,,,,,,
sx-1250,AWS-094,C1,220,6,cea,,220,6.3,647-UPW0J221MED
 
Thats the one!! Thank you for that, I was a bit busy and didn't have time to search....
 
Oh I just wanted to add to this, that this list includes the Panasonic Film caps which are no longer manufactured so it needs updating if anyone is intending on using it...
 
It sounds like this might have been the problem all along, if these voltages are off, the unit will go into protection.

Search SX1250 BOM and compile a list to completely rebuild the stabiliser.
Just replacing caps in these amps is not enough these days, especially that particular board.
You need to replace all the transistors, diodes, and Zeners, I also replaced some of the resistors as well, three I think, the most stressed ones, and of course the two trimmers
Once you have done this you'll be set and good to go. If there is an issue after that, I will know exactly what the problem will be.
I redid the board using parts as listed and replaced the trimmers, still vr1 65 v . vr2 -50v . the unit does no go into protection.
 
I redid the board using parts as listed and replaced the trimmers, still vr1 65 v . vr2 -50v . the unit does no go into protection.
Just need to verify you have -87.5 at Pin 15.
We know pin 13 is -50VDC
But also get us a reading off Pin 14, should be -25VDC.
 
Just need to verify you have -87.5 at Pin 15.
We know pin 13 is -50VDC
But also get us a reading off Pin 14, should be -25VDC.
So do i pull back the connector to expose pins and test 15 using 12 for ground and 14 . using 12 for ground?
 
So do i pull back the connector to expose pins and test 15 using 12 for ground and 14 . using 12 for ground?
Oh, what I did was had the unit on the side with the stabiliser near the bottom, then I had it removed from the unit and I just flipped the molex connectors over and ran it flopped over so the board was hanging out the bottom, this way its easier to measure things. Less likely to short something out....
I might have a pic, I'll post it if I do in case I am talking gibberish and not making sense...
 
Oh, what I did was had the unit on the side with the stabiliser near the bottom, then I had it removed from the unit and I just flipped the molex connectors over and ran it flopped over so the board was hanging out the bottom, this way its easier to measure things. Less likely to short something out....
I might have a pic, I'll post it if I do in case I am talking gibberish and not making sense...
I would appreciate the photo thanks
 
I would appreciate the photo thanks
Looks like I didn't take a pic, which is unusual for me.....:yikes:

You can do it whatever way you are comfortable doing, just be careful not to slip and short something out.....
 
I have -96vt at 15 . 2.6vt at 13
Okay, thats weird, you say at the test point its -50V?
Are you sure you're on 13? That is the -65V rail, and you were saying on the test point you had -50V?
And what is 14?

As a side note, this is looking very similar to the problem I had, but get in there and have a second look and make sure all the information is correct.
 
Okay, thats weird, you say at the test point its -50V?
Are you sure you're on 13? That is the -65V rail, and you were saying on the test point you had -50V?
And what is 14?

As a side note, this is looking very similar to the problem I had, but get in there and have a second look and make sure all the information is correct.
I had -50vlt at 16 and ground, 65vlt 17 and ground . -96vlt at 15 and ground and 2.6vlt at 13 and ground stabilizer board
 
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