Bottlehead Forum

Bottlehead Kits => Legacy Kit Products => Topic started by: vetmed on December 04, 2017, 05:03:28 AM

Title: S.E.X. 2.0 power supply
Post by: vetmed on December 04, 2017, 05:03:28 AM
This is the one that uses aWE power supply, with 2 HV windings and a voltage doubler for each channel. One of the electrolytics went up in smoke yesterday. There are 2 per channel, should I replace all of them or just the one that blew?
Thanks
Title: Re: S.E.X. 2.0 power supply
Post by: Paul Birkeland on December 04, 2017, 05:18:18 AM
Which electrolytic went out on you?
Title: Re: S.E.X. 2.0 power supply
Post by: vetmed on December 04, 2017, 06:40:22 AM
One of the ones in the voltage doubler.
Title: Re: S.E.X. 2.0 power supply
Post by: Paul Birkeland on December 04, 2017, 06:59:51 AM
I would go ahead and start by replacing the blown one, then do voltage checks.  If everything checks out OK, then consider doing the rest.
 
The 220uF/250V Panasonic TS snap in caps are NLA, so I'd snag some of the venerable Panasonic ED leaded radial caps here (https://www.digikey.com/product-detail/en/panasonic-electronic-components/EEU-ED2E221/P13533-ND/1086759).  There's a matching 47uF/450V cap that you might want to grab a pair of also, just in case here (https://www.digikey.com/products/en/capacitors/aluminum-electrolytic-capacitors/58?k=47uF+450V&k=&pkeyword=47uF+450V&s=1047&FV=mu47%C2%B5F%7C2049%2Cffe0003a%2Cfffc000a&mnonly=0&ColumnSort=0&page=1&stock=1&quantity=0&ptm=0&fid=0&pageSize=25).

The real question is why one of the doubler caps went out in the first place.  That may not be answerable without replacing the blown cap and measuring voltages.
Title: Re: S.E.X. 2.0 power supply
Post by: Doc B. on December 04, 2017, 07:19:10 AM
Had the amp been sitting unused for a long time, or was it in service when the cap went?
Title: Re: S.E.X. 2.0 power supply
Post by: vetmed on December 04, 2017, 08:14:15 PM
Well in all fairness these are old and the amp had not been powered up in at least 6 months ??? Just thinking that i would probably save myself a lot of grief by replacing all the caps at one go. Not concerned about cost just want to put off future problems as long as possible :)
Title: Re: S.E.X. 2.0 power supply
Post by: Doc B. on December 05, 2017, 05:20:57 AM
Six months is not a big deal. So my hunch would be, as PB suggests -  that something other than the cap itself created the problem. You should probably start by doing the resistance checks.