Edit: Completed December 6, 2018 (Six Months)
Final setting of idle and bias (25mV which is DIFFERENT than manual specs -- see Larryderouin Post #2), and put the cover on. Probably going to get it aligned.
Thanks everyone for your help on this. Sorry it took so long. Had a lot gong on.
I will go through in the next couple of days and tidy up the parts lists in this thread so they reflect what actually went in
Thanks again.
_______________________________________________________
Here is now the thread originally began!!!
...AND SO IT BEGINS.
Pioneer SX 939 which is going into protection. This will be full restoration. I am planning on taking my time which means the project will go on for several weeks.
Openning hypothesis: the issue that is causing it to go into protection could be something as simple as the 2SC1451 transistors in the Power Amplifier. Edit: could also be something in the protection circuit like a C5 changed in capacitance value due to age and wear.
I've gone through and verified by visual inspecton what is actually installed (in the Power Supply, Protection Circuit and Power Amplifier).
Can I get some help with my initial component selections? Let's start with the Power Supply (and then I am going to run by you also the Protection Circuit and Power Amplifier).
Thanks!!!
DRAFT DRAFT DRAFT -- DO NOT USE -- THIS LIST IS UNDER DEVELOPMENT!!!
AWR-052-0 Power Supply
AWR-052 C11 47uf 63v cea up it to 100V 647-UPW2A470MPD
AWR-052 C12 47uf 50v cea up it to 100V 647-UPW2A470MPD
AWR-052 C13 470uf 80v ach-038 up it to 100V 647-UPW2A471MHD
AWR-052 C14 470uf 80v ach-038 up it to 100V 647-UPW2A471MHD
AWR-052 C15 100uf 63v cea 647-UPW1J101MPD
AWR-052 C16 100uf 63v cea 647-UPW1J101MPD
AWR-052 C17 47uf 16v cea up it to 25V 647-UPW1E470MDD
AWR-052 C18 47uf 16v cea up it to 25V 647-UPW1E470MDD
AWR-052 C21 47uf 50v cea up it to 100V 647-UPW2A470MPD
AWR-052 C22 2200uf 10v cea 647-UPW1A222MHD
AWR-052 C23 220uf 16v cea 647-UPW1C221MPD
AWR-052 C24 1000uf 35v ach-039 647-UPW1V102MHD
Filter Caps
C1 10000UF 50V up it to 12000uF 63V 647-LKS1J123MESC
C2 10000UF 50V up it to 12000uF 63V 647-LKS1J123MESC
Q1 2SD313 KSC2073 512-KSC2073H2TU
Q2 2SC1318 KSC2383Y or KSC2690AY
Q3 2SC1318 KSC2383Y or KSC2690AY
Q4 2SB507 KSA940 512-KSA940TU
Q5 2SA720 KSA1013
Q6 2SD313 KSC2073 512-KSC2073H2TU
Are there recommended power supply resistor replacements in a SX-939 restore???
Reason I am asking is I think in the case of a SX-1010 Mattsd might have recommended replacing four. R11 and R12 are the +56/-56 feeds; R20 is the 13V feed and R21is the 35V feed. Cannot remember if this was Mattsd standard operating procedure or because in the particular thread the power supply was fried. Again these are resistor and voltage identifications in the SX-1010 and DO NOT reflect identifications of what would be corresponding in the SX-939.
R11: 10 Ohm 1/4 watt: 660-MFS1/2DCT52R10R0 10 Ohm 1/2 watt
R12: 10 Ohm 1/4 watt: 660-MFS1/2DCT52R10R0 10 Ohm 1/2 watt
R20: 3.3 Ohm 1/4 watt: 660-MF1/2DCT52R3R32F 3.32 Ohm 1/2 watt
R21: 10 Ohm 1/4 watt: 660-MFS1/2DCT52R10R0 10 Ohm 1/2 watt
Final setting of idle and bias (25mV which is DIFFERENT than manual specs -- see Larryderouin Post #2), and put the cover on. Probably going to get it aligned.
Thanks everyone for your help on this. Sorry it took so long. Had a lot gong on.
I will go through in the next couple of days and tidy up the parts lists in this thread so they reflect what actually went in
Thanks again.
_______________________________________________________
Here is now the thread originally began!!!
...AND SO IT BEGINS.
Pioneer SX 939 which is going into protection. This will be full restoration. I am planning on taking my time which means the project will go on for several weeks.
Openning hypothesis: the issue that is causing it to go into protection could be something as simple as the 2SC1451 transistors in the Power Amplifier. Edit: could also be something in the protection circuit like a C5 changed in capacitance value due to age and wear.
I've gone through and verified by visual inspecton what is actually installed (in the Power Supply, Protection Circuit and Power Amplifier).
Can I get some help with my initial component selections? Let's start with the Power Supply (and then I am going to run by you also the Protection Circuit and Power Amplifier).
Thanks!!!
DRAFT DRAFT DRAFT -- DO NOT USE -- THIS LIST IS UNDER DEVELOPMENT!!!
AWR-052-0 Power Supply
AWR-052 C11 47uf 63v cea up it to 100V 647-UPW2A470MPD
AWR-052 C12 47uf 50v cea up it to 100V 647-UPW2A470MPD
AWR-052 C13 470uf 80v ach-038 up it to 100V 647-UPW2A471MHD
AWR-052 C14 470uf 80v ach-038 up it to 100V 647-UPW2A471MHD
AWR-052 C15 100uf 63v cea 647-UPW1J101MPD
AWR-052 C16 100uf 63v cea 647-UPW1J101MPD
AWR-052 C17 47uf 16v cea up it to 25V 647-UPW1E470MDD
AWR-052 C18 47uf 16v cea up it to 25V 647-UPW1E470MDD
AWR-052 C21 47uf 50v cea up it to 100V 647-UPW2A470MPD
AWR-052 C22 2200uf 10v cea 647-UPW1A222MHD
AWR-052 C23 220uf 16v cea 647-UPW1C221MPD
AWR-052 C24 1000uf 35v ach-039 647-UPW1V102MHD
Filter Caps
C1 10000UF 50V up it to 12000uF 63V 647-LKS1J123MESC
C2 10000UF 50V up it to 12000uF 63V 647-LKS1J123MESC
Q1 2SD313 KSC2073 512-KSC2073H2TU
Q2 2SC1318 KSC2383Y or KSC2690AY
Q3 2SC1318 KSC2383Y or KSC2690AY
Q4 2SB507 KSA940 512-KSA940TU
Q5 2SA720 KSA1013
Q6 2SD313 KSC2073 512-KSC2073H2TU
Are there recommended power supply resistor replacements in a SX-939 restore???
Reason I am asking is I think in the case of a SX-1010 Mattsd might have recommended replacing four. R11 and R12 are the +56/-56 feeds; R20 is the 13V feed and R21is the 35V feed. Cannot remember if this was Mattsd standard operating procedure or because in the particular thread the power supply was fried. Again these are resistor and voltage identifications in the SX-1010 and DO NOT reflect identifications of what would be corresponding in the SX-939.
R11: 10 Ohm 1/4 watt: 660-MFS1/2DCT52R10R0 10 Ohm 1/2 watt
R12: 10 Ohm 1/4 watt: 660-MFS1/2DCT52R10R0 10 Ohm 1/2 watt
R20: 3.3 Ohm 1/4 watt: 660-MF1/2DCT52R3R32F 3.32 Ohm 1/2 watt
R21: 10 Ohm 1/4 watt: 660-MFS1/2DCT52R10R0 10 Ohm 1/2 watt
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