On Fri, 5 Mar 1999 16:49:37 -0500 (EST) "William L. Fuqua III"
<wlfuqu00@pop.uky.edu> writes:
>
> My catalog has a "Allowable ripple current vs. Ambient temperature"
>chart
>for the
>GQ series cap.
>
>Temperature +45 +60 +70 +85 +105
>Coeffecient 2.47 2.37 2.17 1.67 1.00
>
>So at 85 degrees the maximum allowable ripple current for the GQ would
>
>1.67*1.19= 1.99A. That is more than that of the LQ or LK at 85
>degrees.
>So these caps must not be so bad after all for only 2.25 each.
>I did not realize how much discussion my first post would start. HI HI
>
>HI HI This is a 94 catalog.
> I'm not saying a 105 degree cap is always better than 85 degree
>one.
>But in this case it is.
>
> What is the actual RMS ripple current? According to a book I have
>it
>is 1.41 of dc output for a capacitive input filter, fullwave
>rectifier
>with an rectifier effeciency of 100 percent.
> For a 1 amp plate current power supply the cheap ALL Electronics
>capacitors should work just fine especially at 85 degrees c.
>
>73
>Bill wa4lav
But following the lead of hams in general you missed some important
points.
Are those caps factory rejects
Are they at the extreme ends of the tolerance specs?
What are the tolerance specs since that is important when selecting the
maximum allowable equalizing resistor.
What are the datecodes..do they all match when you buy 10 or so?
All too many hams are just that...hams. Price is their only concern.
For someone with a university adr I am suprised that you accept something
at a surplus sale advertisement face value and show no concern with
actual performance data.
Yes, they may be fine but a cavalier attitude can be dangerous and
misleading.
73 Carl KM1H
>
> William L. Fuqua III P.E. E-mail WLFUQU00@POP.UKY.EDU Phone (606)
>257-4155
> Department of Physics and Astronomy CP-177 Chem. Phys. Bldg.
> University of Kentucky , Lexington, Ky 40506-0055
>
>
>
>
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>
>
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