I admit I did not consider the ripple current parameter. The original
Mallory CGSs are rated at 2.9A, 85C. The GU-series Nichicons are rated at
1.85A, 105C. Not too different. I will be the test case for longevity.
The originals lasted only 18 years.
I also found that Nichicon makes a high ripple current cap, series GW. This
one is rated at 2.65A, 105C and, strangely, is slightly _smaller_ than the
ones I used.
73,
John, W1JA
----- Original Message -----
From: "Dr. Gerald N. Johnson" <geraldj@storm.weather.net>
To: <tentec@contesting.com>
Sent: Tuesday, February 19, 2008 10:04 PM
Subject: Re: [TenTec] Titan 425 shelved for 10 years
I am reluctant to use the physically smaller Nichicon capacitors because
I believe them to be rated for a much smaller ripple current and I fear
they will overheat in the transmitter power supply. A power supply
running an amp load requires lots of ripple current in the filter
capacitors, especially if the power supply is a voltage doubler as many
ham PAs are. Look up the data sheets on the computer grade vs the
Nichicon capacitors. The large physical size for the capacitance is why
I like the TVA atoms for axial lead capacitors for better heat
dissipation over the super small off shore capacitors. When I've checked
data sheets for ripple current ratings, the super small capacitors have
been lacking.
73, Jerry, K0CQ
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