• 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

Main PS Caps for SX-1250

ccheath

ccheath

Got an Idea!
Subscriber
Hi, I posted recently about the Main PS Caps for SX-1010. Now this is for my SX-1250. I been looking at PercyAudio for 22,000uf 80v Nichicon KG Gold (Super will not fit) and the problem is it's lug terminal rather than screw terminal. I looked at ApexJR and they carry Hitachi brand caps 22,000uf 100v for $16 each. Is it a worthy cap to consider or should I look for something like Cornell Dubilier? If CDE is suggested, where can I buy 4 caps without having to buy 10 or more minimum as required in Digikey? Again thanks in advance.
 
Register to hide this ad
Hello.
The Caps that EW recommended fit perfectly in the chassis and sound great but you will need to enlarge the terminals as they are for a 8/32 screw and the new Caps have a 10/32 screw.
I posted a picture in the same thread that EW refered to post #18.
 
Stevesmullen said:
Hello.
The Caps that EW recommended fit perfectly in the chassis and sound great but you will need to enlarge the terminals as they are for a 8/32 screw and the new Caps have a 10/32 screw.
I posted a picture in the same thread that EW refered to post #18.
Click to expand...

Dang! That's a good pic. It may not be black but if the cap is best for this purpose, that's the reason I'd pick them. :yes:
 
I just placed an order for 4 United Chemi-Con 36DA223F100CD2A. Echo has suggested this to be the best cap for the job. Thanks Echo. :thmbsp:
 
Hey ccheath.
Be sure to take a picture of were the negative and positive leads go,even though it is very simple even EW says that he does one side at time so as not to mix anything up.
Could be a costly mistake.
It probobaly wouldnt hurt to check your DC Balance and your Idle current of the power Amps and the Output voltage of the power supply as shown on Page #38 of the SM.I have been told by EW that the resistors in the Preamp Amp jacks are not neccessary. Be sure to check the setting again after the receiver has been on for 20 minutes or so.
If you allready know all this then just ignore me (as my wife does:) )
Steve
 
Stevesmullen said:
even EW says that he does one side at time so as not to mix anything up.
Click to expand...
At this point, I've done enough 1250's that I could likely do it blindfolded. ;)

At any rate, all the negatives face the front of the receiver. Easy to remember (but make sure someone hasn't fooled with this arrangement by double-checking!).
 
Stevesmullen said:
Hey ccheath.
Be sure to take a picture of were the negative and positive leads go,even though it is very simple even EW says that he does one side at time so as not to mix anything up.
Could be a costly mistake.
It probobaly wouldnt hurt to check your DC Balance and your Idle current of the power Amps and the Output voltage of the power supply as shown on Page #38 of the SM.I have been told by EW that the resistors in the Preamp Amp jacks are not neccessary. Be sure to check the setting again after the receiver has been on for 20 minutes or so.
If you allready know all this then just ignore me (as my wife does:) )
Steve
Click to expand...

This is actually the same SX-1250 I worked on about 6 months ago. The regulator board had several bad caps and the bias was sizzling hot (around 350ma) on one channel. 3 of 4 main caps were showing sign of losing capacitance but sufficient enough to do the job for awhile until I'm ready to totally recap the entire receiver. I knew that the caps are arranged in a way that one cap positive side goes to ground while the other cap negative goes to ground. In several receivers I worked on would have red wire as positive rail and orange as negative rail while black is ground. A while back, I have built a 65 watt amplifier and it was successfull. It required +50v and -50v rails. One thing from looking at schematic, I KNEW not to disconnect any of the 3 wires (+ gnd -) while energized. In doing so can destroy an amp. Well, even though knowing about it, I was not thinking right at the moment when I accidentally disconnect the positive rail from my 65 watt amp while energized then in panic reconnect. That destroyed my project amp. That was like 7 years ago. If I "accidentally" disconnect ANY wire from my 1250 while energized, I'd just go to Grand Canyon and jump off the cliff. :D No, I know better. ;) But your words I will not ignore but take as a reminder even though I remember. It can get costly if I ignore you. I may learn something from you that I may not have thought of. :yes: About the bias and dc offset, yes, I am finatic about it. In another thread awhile back, Glenn said anyone trying to adjust dc offset any lower than 20mv had nothing else to do. In the other words, 20ma or less is fine. After reading that, I still adjusted the dc offset so close to 0mv whereas I was able to get it down to about 2mv or less. In my SX-780 I was able to get 1mv or less. (Yes, I'm real picky! :D)

EchoWars said:
At this point, I've done enough 1250's that I could likely do it blindfolded. ;)

At any rate, all the negatives face the front of the receiver. Easy to remember (but make sure someone hasn't fooled with this arrangement by double-checking!).
Click to expand...

Yes, you did a lot of SX-1250s and made a lot of happy customers. You probably would have to work on mine if I have decided not to do it myself. But hey, you're saved because I am going to work on mine. :D

It didn't look like anyone have fooled with the arrangement (fortunately). All the caps are still original and no mod was done to the terminals. The orange are facing front while red is facing back. Yes, I will definitely double check.:yes: One question, I recall seeing one thread that you had suggested to use 1.8uf film cap in parallel with the main cap to handle high frequency better in some receivers since large electrolytics don't handle high frequency well. Would you suggest doing the same on the SX-1250 using film caps in parallel with the United Chemi-Con caps?
 
I usually use some inexpensive 2.2µf 250V Mylar (metallized polyester) caps, but yeah, if you want the best results, bypass the big caps with a decent film cap. Any good film cap from .47µf to 3.3µf will do.
 
EchoWars said:
I usually use some inexpensive 2.2µf 250V Mylar (metallized polyester) caps, but yeah, if you want the best results, bypass the big caps with a decent film cap. Any good film cap from .47µf to 3.3µf will do.
Click to expand...

Is this cap good for this application?

http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail?name=PF2225-ND




STEVE, you have given me some idea I haven't thought of on the spreadsheet you made in your thread. It does help me get sorted better on making the list for my receivers. Thanks.
 
Sure...it's just more expensive than necessary. I use the polyester cap, P10983. There isn't much difference in price when you're buying only a couple, but I order 50 or so at a time, and in this case they are a lot cheaper.
 
The Nippon caps arrived today. I can't imagine this perspective with 4 caps that large are going to be in one receiver even though I seen the ones inside. All 4 are rated 22,000uf and I tested them and found all 22,000 range from 22,200 to 22,600. At least they're 22,000uf range. Alot better than my old ones that tested in range of 21,000uf down to about 17,000uf. Now, only thing to do is make up the list of caps to order plus I am considering Echo's recommendation on polyester caps pricewise. Since, I'm only getting 4 for SX-1250 and 2 for SX-1010, would I get any better using Polypropylene vs Polyester or will they be the same?
 
You must log in or register to reply here.
Back
Top Bottom