Hi Robert,
This defect is very common and well known for the FT-980. I have also had this problem as have many other owners.?
They are indeed tantalum capacitors marked (T). They have the defect of shorting out due to aging. Tantalum capacitors were chosen for their long life and low ESR (equivalent series resistance).
I recommend you to replace all the tantalum capacitors as long as the PA is dismantled. It may be another one that will blow later...
Currently, tantalum capacitors are not justified with the progress of aluminum capacitors. Based on my professional experience in automotive electronics engineering, aluminum capacitors of class 105°C or higher are just as good and do not have the defect in short circuit.
You can replace C22 3.3?F by 4.7?F 50V and all other 10?F(T) by 10 to 22?F 50V aluminum 105°C.
Take care of the polarity ! A reverse capacitor can explode !
73 de F5RCT Jean-Matthieu (JMat)
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