I ham looking at the SSE schematic and was wondering where folks use motor run caps? Are they necessary?
Which caps are the motor run caps?
I am a tube noob embarking on my first build ... exciting stuff!
Thx,
Rob
Which caps are the motor run caps?
I am a tube noob embarking on my first build ... exciting stuff!
Thx,
Rob
80 uf 500 VAC Oil Filled Motor Run Capacitor Eyuda - eBay (item 310195976442 end time Feb-18-10 09:49:47 PST)
It goes in after the choke, its called "optional aux cap"
Motor run caps are the big metal ones that are normally oil filled. They handle alot more abuse and last alot longer under load then stock electrolytic. Other then ubber high voltage requirements im still not sure why everyone uses $15 motor run caps and not a 2nd $3 electrolytic cap.
It goes in after the choke, its called "optional aux cap"
Motor run caps are the big metal ones that are normally oil filled. They handle alot more abuse and last alot longer under load then stock electrolytic. Other then ubber high voltage requirements im still not sure why everyone uses $15 motor run caps and not a 2nd $3 electrolytic cap.
motor start and motor run caps both come in either electrolytic or film type.
The electrolytic may not offer any benefit over normal high voltage electrolytics.
The film type are used because they allegedly improve the sound quality. They are bigger and more expensive.
The electrolytic may not offer any benefit over normal high voltage electrolytics.
The film type are used because they allegedly improve the sound quality. They are bigger and more expensive.
I am using 2 electrolytic caps (400WV 300uF) in row, signifficant improvement in sound... but have not tried motor run caps, so cant tell the difference...
Heh, 80 uf 500 VAC Oil Filled Motor Run Capacitor Eyuda 13$, transportation as follows:
US $19.64 Estonia USPS First Class Mail InternationalTM
And someone once was surprised how I managed to spend 900$ to my SSE
Film caps have really low ESR, which improves the dynamic response of the power supply. Surplus motor runs are a really cheap way to get a big film cap there, but the point is that it is a film cap and not another electrolytic.
Sorry albireo13 for posting my question here, just wanted to ask if anyone know a good online shop in Europe to buy MRC? Have spend some time, but have not succeeded to find any...
Sometimes it's hard to tell, but here are some clues: If it says oil, then you know it is film in oil (some are just film, which is OK too). If it has polarity markings, it is electrolytic.
Rob,
I'll second the recommendation for the Eyuda motor run caps. The people on ebay who sell them are great to deal with. These are big suckers, so make sure your chassis has the space. You can see what they look like by going to my post (Gratuitous shots of my new SSE). I think the motor run cap and Triad choke helped a great deal in making my SSE totally hum-free.
Regards,
"The Cat"
I'll second the recommendation for the Eyuda motor run caps. The people on ebay who sell them are great to deal with. These are big suckers, so make sure your chassis has the space. You can see what they look like by going to my post (Gratuitous shots of my new SSE). I think the motor run cap and Triad choke helped a great deal in making my SSE totally hum-free.
Regards,
"The Cat"
I find these folks to be pretty reasonable: https://www.surpluscenter.com/sort.asp?UID=2348030421105241&catname=electric&keyword=EMRC I haven't purchased mail order, as I'm often in the neighborhood. I picked up 4 60uf pieces last time I was in town. They are cheaper than some other surplus places.
I'm not sure I should admit it, but my tube amp power supply is filled with motor runs that I bought as salvage from an appliance recyclers in Minnesota. They mostly came from air conditioners, and I figured there is no way an AC unit in MN can have enough hours to exceed the life span of the cap. They are still going strong, and I bought them (six in that supply if memory serves) for forty cents a pound. I still have a few kick around in a parts bin. If you've got a local appliance recycler and a sense of adventure, you might ask. $10 will buy a pretty large pile.
Paul
Wild Burro Audio Labs - DIY Full Range Speakers
I'm not sure I should admit it, but my tube amp power supply is filled with motor runs that I bought as salvage from an appliance recyclers in Minnesota. They mostly came from air conditioners, and I figured there is no way an AC unit in MN can have enough hours to exceed the life span of the cap. They are still going strong, and I bought them (six in that supply if memory serves) for forty cents a pound. I still have a few kick around in a parts bin. If you've got a local appliance recycler and a sense of adventure, you might ask. $10 will buy a pretty large pile.
Paul
Wild Burro Audio Labs - DIY Full Range Speakers
Although you need to look at AC voltage, quality etc, you will have a fair idea by simply looking at the dimensions. If it is 50uF to 100uF and much smaller than 8cm high and 5cm across, it will probably be an electrolytic. That said, I wouldn't be buying from those who can't tell you brand, origin, ratings etc as it will cause you all sorts of trouble. Also, some may list Motor Start Caps as Motor Run Caps, be weary of this. A Motor Run Cap is designed for continuous operation, while a Motor Start Cap is only designed to be run for a few seconds at a time, to help turn power hungry electric motors over.
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