Amps
[Top] [All Lists]

[Amps] cap ratings in tank ckt

To: <amps@contesting.com>
Subject: [Amps] cap ratings in tank ckt
From: K1LE@ARRL.NET (Jeffrey Madore)
Date: Wed, 4 Sep 2002 14:09:57 -0400
Gentlemen,

I'm repairing the pa board (100w) in an Icom 275H and need to replace all 3
of the monolithic chip capacitors in the output circuit, as they are burned
open. I also need to replace the ceramic DC blocking capacitor between the
tank coil and the antenna.

My questions are:

Where is a good place to purchase these caps?  Icom has all but one of them,
but they want $6 to $8 each for a chip cap. I haven't bought these types of
devices but that seems like a lot. In addition, Icom tech support says that
they can't supply a replacement component for the one that is no longer
available...I would have paid their price if they could have just given me
what I needed.

Secondly, the Icom service manual shows only capacitance values. What would
be a conservative voltage rating for caps in a 12 volt 100w pa tank circuit?

Chip capacitors are really new to me. Is there any one type that would be
preferable in an RF power application?  What % tolerance is acceptable?

Thanks for any help. I need to repair this radio such that it will be
dependable, as I plan to sell it. If it's any less than perfect, it will
stay on the bench...maybe become a signal generator ;-)

Tnx es 73,

Jeff - K1LE ><>


<Prev in Thread] Current Thread [Next in Thread>