Seems to me the R7000 has been the model having problems. The R7 worked
for me as an RV antenna with lots of "ups and downs" ... never any
problem. So, I would suggest you find a used R7.
On the subject of radials, the only thing I learned from Cushcraft was
to mount it about 8 feet above any metal (roof, gutters, etc.). I had
mine on a 22-foot length of SS-20 top rail and it worked fine.
Fred Roberts, W6TKV
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