At 03:42 PM 1/18/00 +0000, Peter Chadwick wrote:
>Naive question: photoflash type caps are obviously designed for a high peak
>current, albeit intermittently. One would presume that they are designed for
>low ESR, but if that's so, why do they give up pretty rapidly under high
>ripple conditions?
>
>73
>
>Peter G3RZP
Hi Peter,
Nice to see you back.
Do you mean the crummy little electrolytics sold cheap by the surplus
places like ALL ELECTRONICS, or the large oil "laser caps" such as sold by
Fair Radio?
I have been using the laser type jobs for years with never a failure. Of
course, I never overvoltage them, usually only use them in choke input
supplies, and never, ever leave the HV on when not actually transmitting.
The oldest one is about twenty or so years old now and is still fine. The
latest I got from Fair Radio a few months ago and is the first one I've
ever used in a capacitor input supply. I'll have to let you know how that
works out in twenty years or so.
I'm looking forward to more from you Peter. Hope you are back up to snuff.
73,
Larry - W7IUV
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