• The move to the new server is done. There are some software and database maintenance updates in process. This has us passing the hat around to help out. We appreciate any donations. Seriously, even a dollar helps. The payment page may be found here - https://www.audiokarma.org/support.html

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

leave them out of one channel of the easier board to get to.

After you hear the difference, we won't need to urge you to order the rest.

Or mix them through both channels and never hear a difference.

The SA-9500 taught me several lessons about capacitors.
 
Oh I will absolutely be buying more film caps and replacing the electrolytics. Mouser are out of a few types of MKS2 caps at the moment which why I came up short. I thought I double ordered the 4.7ufs, the 2nd set were holding up the order because they were out of stock. I had the the back-ordered lot cancelled because I was thinking they were just surplus.

I will be putting in orders for my ReVox A77 MKIV and B77 MKII soon, so I will get more then. I also want to have enough MKS2's to put in my SA-9900 and SA-7500. I also plan to buy another 9500, 9900 or SPEC 1 as soon as I can so I can't have too many!

I will add some photos of the insides of the 9800 so the differences with the 9500 can be seen. The power amp board is a bit different. Especially the placement of the metal resistors.
 
i own both 9500 and 9800. :) the 9800 is a NSA amp that is radically different from the 9500


of course they both are waiting for work, 6 years minimum.
 
Last edited:
markthefixer said:
i own both 9500 and 9800. :) the 9800 is a NSA amp that is radically different from the 9500


of course they both are waiting for work, 6 years minimum.
Click to expand...

When I say SA-9800 I am referring to the Japanese model, which is a 9500. I am not quite THAT dopey ;) Only difference is a small badge on the front that says 160 watts. The Jp 9900 also has the same badge, but with 220 of course :p

Man, I WISH it was a Western 9800!! Love the look of that thing. I have yet to get my hands on a blue scan cassette player because the prices suddenly sky rocketed. Wanted it only to complete a set. Have R2R decks so cassettes are useless. Sadly, one of those is not an RT-909. Another item I should have bought in 2017! They are incredibly rare here.

The 1250 which I almost bought in 2017 for $280 is suddenly $1200-2000 depending on the idiocy of the seller. Much cheaper in Japan before shipping (though not that cheap), but Jp blue scan models are not actually "blue scan". I was so disappointed when I saw the yellowish lights on a CT-920.

On the topic of different model numbers, is there a guide somewhere that lists the Jp equivalent of Western model numbers? I saw the guide to reading serial numbers to determine year and month of manufacture, but I lost the link. Want to know when mine was made. It looks like it was bought just a few years ago, it is so pristine and lacking the usual rust that most Pioneer amps seem to suffer from due to bad storage.
 
markthefixer said:
MY post was the dopey one.... I was that dopey!!! then on top of it, i had to brag..... SMH
Click to expand...

All good! Still very jealous of that "real" 9800 though ;)

I hit a snag on my first board today, the power amp board. It seems I did not order KSA940TU transistors for the 2SB536's. So that tells me that it was not on the BOM I copied. Looking at the sub lists, only the 940TU is listed for the 2SB536. Is there anything else I can use? MJE1503xG? I have the 32, 33 and 34G listed for the 2SA816 and also listed the KSA940TU later on.

I cannot find the BOM I used from this site to see what they had listed. I was so happy to finally start this thing today, wanted to get the power amp out of the way first because it is the most annoying part to get to. I am dying to get the board back where it belongs but while I have no transistors to install, I don't want to do that.
 
Last edited:
Damn, the solder on some of the boards is TOUGH! I always have my desoldering station set to 300 which has always worked perfectly, melting and sucking in 2 or 3 seconds. The solder on the power board though, man, it just refuses to melt.

I am picking up some parrot clips for my DMM today, so I will also grab some desolder braid. I will have to do it the old way and be EXTREMELY careful. I am determined to get through this "ordeal" with no damaged pads. Apart from the control amp, grrrr.

The power board is also a tad scary because every goddamned pin is bent and against the board. The two legs I managed to suck the solder from, I also straightened up as I usually do but the problen is that the legs pulled lacquer off the board where they were laying. Arrrgh, slow and careful is how I shall go! I did put the transistors in the power board and that was it. Went to the tone board after that which was much better! Except for the two larger caps. They had the terrible non-melting solder and were of course, bent against the damn board. So they will have to be desolder braided as well. Wish me luck, guys! I want my amp singing tomorrow!

I have a mint UK first press 1E/1E Ziggy Stardust sitting here that I am dying to play. Plus a pile of Stones and other Bowie that I want to play! Looking forward to hearing the difference in the sound. It may have been my imagination, but the phono sounded so much better after I changed the transistors on the control board. Even though it was one channel.... should have played some Beatles, Hendrix or Doors mono!
 
Oh one other thing, any tips on managing the protection board? Does the whole side have to be removed so the board can be pulled down flat? Or will taking the wires out of the holders give enough slack?

Same with the phono board. Do the black metal parts have to be removed to get to the board or do people usually just desolder from the bottom with everything intact? The phono transistors are of course, under a part of the metal. It looks like I may be able to get them in there with some pliers and patience, but I don't want the control amp disaster to happen again!
 
Had a few mishaps on that damned control board, but continuity checks out. I just hope to christ it works! I wouod seriously buy a new one if I ever saw one for a half decent price. Deffinately not the one on ebay with the idiot price of AU$411!! The amp only cost me ¥16,000!

Every other board is perfect, just this one board has given me problems. The pads looked fine, but on a couple of them the damn pads lifted when I pushed the new cap legs through! I was so pissed! One time, I was fixing the way the cap sat on the board, lightly pushing as I melted the leg solder to ensure the cap is straight and flat and the opposite pad popped right off when I did not even have pressure on that side, grrrrr! The trace started to lift on two as well.

Man, there always has to be one! I feel like the problems on the control amp board are partly due to running out of desolder braid. There may have been a scrap of solder on the pad because my shitty Chinese desoldering gun is ****. Too bad I only bought one, damn... I thought it would be plenty but there was so much solder on the power and tone board that I went through it bery quickly. I really think the braid would have saved those pads. Damned bent pins!
 
Well..... finally finished the board a little while ago anf tested it out. It popped the 6a fuse underneath the board. I hope someone is reading this as I could use some help :D

My first thought was the dodgy control board connections, but I just now though about the outputs. I put the outputs from my AU-9900 and put them in the SA-9500. If one or more of the outputs are fooked, could that blow the fuse? It is possible that the Sansui screwed tye new outputs. I do not want to put the old ones back in before I know it is safe. Thankfully the fuse did its job and seems to have stopped any further damage.

So, fooked outputs or dodgy connections on the control board? Or something else entirely? There were no lifted pads on any other board and I checked each transistor at least 5 times. But, could it be something on a power board? Where should I start with this?

Any help is GREATLY appreciated!!!
 
Hehe, thanks :D

Another theory, I changed VR1-4 on the power amp board. I just read a thread about main fuse popping. It turned out to the voltage set too high on the VRs. I was positive I turned them counter-clockwise but I guess it is possible that I was looking upside down....? Hmmmmmm.....
 
Segasonic91 said:
Hehe, thanks :D

Another theory, I changed VR1-4 on the power amp board. I just read a thread about main fuse popping. It turned out to the voltage set too high on the VRs. I was positive I turned them counter-clockwise but I guess it is possible that I was looking upside down....? Hmmmmmm.....
Click to expand...
Are you using a dim bulb for testing? If not and the trimmers are fully on, that could have blown outputs??
 
I don't have my dim bulb tester at the moment, which I know is bad! But I was confident that all would be okay.

I did check the trimmers and the two with finite movement are turned fully counter clockwise. This is looking at them front on, and up the right way.

I am really thinking that one or more outputs were blown before I turned the amp on. That would blow the fuse, correct?

Oh, naturally I have everything BUT 6amp fuses on hand!
 
Last edited:
Segasonic91 said:
I don't have my dim bulb tester at the moment, which I know is bad! But I was confident that all would be okay.

I did check the trimmers and the two with finite movement are turned fuller counter clockwise. This is looking at them front on, and up the right way.

I am really thinking that one or more outputs were blown before I turned the amp on. That would blow the fuse, correct?

Oh, naturally I have everything BUT 6amp fuses on hand!
Click to expand...
Get a bulb inline.... It will save you fuses, outputs! Check your output transistors.
 
You must log in or register to reply here.
Back
Top Bottom