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Update
I think the main cause of the static is interference from KCSM 91.1 that seems to overload the amp in my receiver. To summarize, I split a coax line off my ANT751 TV antenna on the roof then into a balun then into the 300 ohm FM antenna input of my receiver as a test since I had static after trying various indoor folded dipole FM (T) antennas.
The key tip was from ADTech to put in 10-20db loss to rule out an overloaded amp. I didn't have an attenuator handy so I installed a Dish TV Satellite 950-2150 MHz diplexer that was lying around. I actually have it installed backwards with the antenna plugged into the output port and the balun plugged into the Sat1 and the Sat2 port capped with a 75 ohm terminator. This arrangement knocked out most of my stations, at least on auto tune, except 91.1 KCSM and one of the stations I was troubleshooting, KITS 105.3 which was dramatically improved in static level and stereo lock (used to flip mono/stereo before).
This made me suspect KCSM/91.1 as the cause. So after a fruitless search on the internet to find a notch filter or highpass filter that would do the trick, I found this PDF;
http://www.ic.gc.ca/eic/site/smt-gst.nsf/vwapj/solution.pdf/$FILE/solution.pdf
In Appendix 4 it described how to make a notch filter using an open antenna cable stub. I added a stub of twin lead cut to the correct length to the 300 ohm side of my balun and the results were dramatic. Immediately almost all my stations came back even with the high loss Sat. Diplexer in place, many of them are now rock solid in stereo, no hiss or static so it seems like my troubles are solved.
Thanks to all for your help.
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