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SA-9500 rebuild complete but fuse blew when testing, please help!

I will go and grab the things to make another tester tomorrow.

One thing though, I have to use a stepdown 240v-100v transformer with this amp. Is it okay to use a bulb tester with the stepdown plugged it it and the amp in the stepdown? Just wondering if the extra step between the amp and bulb tester makes a difference.

Should I just replace the outputs with the originals? I am pretty sure now that the Sansui killed some of the outputs before I swapped them. Grrr, I KNEW I should not have changed them! I wanted to see if they were okay and was hoping that the 8 outputs were not $200 bucks down the drain. I did not think the damned thing would blow to be honest. I thought one or both channels would just not work.

I did check them though, and they seemed to be okay. I will pull them again and re-test.
 
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this is precisely why when I post (posted in the past) about the initial Idle current pot setting in a thermal diode circuit, I specifically say to set the pot to zero ohms as indicated by an ohmmeter.

Seems to have gotten lost or omitted over time. Because of confusion / error concerning where fully CCW leaves the initial setting.

As for DBT with a stepdown - plug the DBT INTO THE STEPDOWN and the unit under test into the DBT. P.E.R.I.O.D.
 
markthefixer said:
this is precisely why when I post (posted in the past) about the initial Idle current pot setting in a thermal diode circuit, I specifically say to set the pot to zero ohms as indicated by an ohmmeter.

Seems to have gotten lost or omitted over time. Because of confusion / error concerning where fully CCW leaves the initial setting.

As for DBT with a stepdown - plug the DBT INTO THE STEPDOWN and the unit under test into the DBT. P.E.R.I.O.D.
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Hmmm, the part about the DBT will be a problem because of different plug types. The amp and stepdown being the two straight pin plugs and the DBT being two slanted pins with a third straight ground pin. I did have plenty of adaptors because all my consoles are Japanese but since I moved I have no idea where they are. Looks like I will have to look on crapbay.

The pots for the power amp board were deffinately turned counterclockwise. Two seemed to never stop turning, do they eventially stop or are they infinite? I turned them for ages and they just kept turning. From memory, VR 2 and 4?
 
I am having a terrible time finding a 3AG 6 amp, 125v fuse. I found that it is okay to replace a 125v with a 250v though. Makes me curious about the 125v 1amp fuses in my SA-7500 now seeing as it is a 240v model.
 
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Segasonic91 said:
I am having a terrible time finding a 3AG 6 amp, 125v fuse. Is it listed as DC or AC? Mouser lists some fuses as 250v AC and 125v DC. The sm does not specify. Unsurprisingly, the 120v model is the same as the 100v model.
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6A/250vac will do... The difference in the listing is what they are for each AC or DC, that's all. Many things, such as automotive or DC operated equipment need the DC rating of fuses.
 
Kind of expecting them to be screwed, really. Thinking they might have have been screwed before I put them in the Pioneer as I took them out of my cursed AU-9900. I will put the old ones back in when I get the new fuse and test on the DBT. Just have to get some bloody plug adaptors first. Uhhgg, if I only I knew where they were.

Do the upgraded outputs do much for the sound or should I just leave the originals in and not bother spending the money on a new set?
 
Segasonic91 said:
Kind of expecting them to be screwed, really. Thinking they might have have been screwed before I put them in the Pioneer as I took them out of my cursed AU-9900. I will put the old ones back in when I get the new fuse and test on the DBT. Just have to get some bloody plug adaptors first. Uhhgg, if I only I knew where they were.

Do the upgraded outputs do much for the sound or should I just leave the originals in and not bother spending the money on a new set?
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If you have a matching working set, no need to buy new ones. They won't sound different.
 
The Fuxtor said:
You tested the old transistors?
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Not yet, am away from home at the moment. Will test them when I get home.

Still had absolutely no luck finding 6 amp fuses in a shop. Had to order tuem online. Hoping for them to aerive tomorrow but I will not hold my breath.

All these months I have been without an amp, I forgot about the fact that I could plug a turntable into my surround amp. Sounds rubbish compared to my proper amps but at least I will be able to listen to records before the fuses get there!
 
Segasonic91 said:
What is the quickest way to test the outputs to see which ones are blown?
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In circuit? Use your meter to check for shorts between ECB, then check for junctions E-B, C-E, B-E reversing the lead polarity each time and comparing readings to another one. NPN first, then PNP since they will be opposite polarity.
 
PTL-Pioneer said:
I think out of circuit is best, but I'll let those who actually know what they are talking about to advise on that
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It is best, but to do a "quick check" for shorts or open junctions will point you into the right direction. Then of course remove them and their compliment for a proper check. :thumbsup: Plus of course any other components in the chain of the failure.
 
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