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Old 12-03-2012, 2:28 AM
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Shortwave2200 Shortwave2200 is offline
Join Date: Aug 2011
Location: Tampa Florida
Posts: 162

This is a answer to a question I posted on the Panasonic RF2200 group about re-capping:

A cap can have no signs of bulging, and still be defective. High ESR is the
easiest-to-diagnose indicator of a defect, because you do not have to desolder
the cap from the PCB.

On the RF2200, and my quote is valid for THIS radio ONLY, Panasonic used such
high-quality capacitors that it is the rare exception, rather than the rule that
you will find any defective capacitors in this radio.
Do not read any other inferences into the above statement.

Could you have a defective capacitor in this radio? Of course, anything is
possible under the sun, but it is highly unlikely. On other radios, the tendency
is to certainly find defective capacitors, on this radio - not!

Unless your RF and electronic knowledge guarantees that you know what you are
doing with this machine, leave the capacitors alone. There are numerous PI- and
Tank circuits, which require exact capacitor characteristics, and unless you
understand what is going on in these circuits, you will destroy its ability to
do the job.

As someone else suggested to use the Panasonic FC, it is a fine capacitor for
power circuits, but not suited for a willy-nilly recap in this radio.

Of course, it is your radio, and you are free to do with it as you like, but you
may not like the results if you do anything without the proper understanding.

I totally agree with the RF caps not having a need to be replaced with the
2200. The power supply and DC blocking electrolytic caps may need replacement
but I would not do this unless there is a performance issue. Radios that are
stored for a long time may be subject to capacitor degradation, they can corrode
and leak almost like dry cell batteries.
One time I ran into a capacitor issue that was not with electrolytics, it was
a tuning problem with band switching. The service manual talks about this, there
is a range of polystyrene capacitor values to correct this, the manual has a
list. Only problem is sourcing these capacitors. I could not find them so this
project ended right there.
My "el-cheapo" 2200 works fine in the performance area and I will leave it
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