radioman,
you need to stop trying to solve this problem by grounding.
a 100% professional radio station style grounding system will not solve your problem.
do not waste any more time messing with the grounding/ bonding.
the ONLY thing you might want to check are the PL-259 connectors at either end of your coax.
these can be very tricky to solder correctly if you havent done very many of them, and you can inadvertently mess them up by overheating the connectors, and you wont ever see it.
so, if you happen to have another length of coax lying around, try running it from your antenna to the radio and see if it makes any difference.
if not, you are done changing things at your end.
just to clarify, i am not saying that grounding is not important, it is very important.
what i am saying is that the ground system of your antenna has nothing to do with the specific interference that you are experiencing at the moment.
OK? ok.
again you said that your antenna is 35' to the tip.
by this i assume you mean the tip of the antenna, which would put the base of the antenna about 7 or 8 feet above ground.
is that right?
if so, that is a problem that you should fix if at all possible.
first, the kind of antenna you have cannot do what its supposed to do as well as it should be doing it if its not at least 25 feet above ground or so.
really it should be 36 feet to the base of the antenna for it to really perform well, but somehow im guessing that 36 feet is not in the cards at your current location.
just try and get the antenna up high enough to where the base of the antenna (where the coax connects to it) is above the roofs of your house and the surrounding houses by about 10 feet or more.
hey, if you just cant do it, you have to compromise and just do the best you can.
you can still play radio, you just wont get out near as far, and you will have a bigger problem with interference, both transmitted and received.
i am 99% positive that your interference is coming from one of your neighbors houses.
i read where you found that the interference was happening at 5:51am every day, and i think that is a good clue.
the thing is, it might not be the timer that is the problem, it might be the device that is being controlled by the timer.
you are going to have to spend some more time wandering around the neighborhood like a crazy person with a little handheld radio in your hand.
if it were me, i would build a field strength meter to take with me, and when the AM radio finds a source of RF noise, i would then take out the meter to try and pinpoint a direction/ source.
here is a link to a very simple, and easy to build field strength meter:
Project 11 - Field Strength Meters
you can build one entirely out of an old non-working CB radio.
all you need is the meter from the radio, a .001uF ceramic disc capacitor (they are labeled 104 and are all over the PC board), and a 1N34a germanium diode.
(also located throughout a CB radio, they are the large clear diodes with the black stripe at one end)
solder it up like the pictures show, add a piece of wire for an antenna, and voila! you can check/ measure the output of antennas and other Rf emitting devices.
the range will be very small, so you will have to use it after finding a noise source with the AM radio, when you are sure you are close to some RF offender.
you have said often in these threads that you didnt have these problems with your old antenna, and that seems to be leading you down the road of " it must be my new antenna that is the difference".
i doubt that very much, and believe that the difference has much more to do with the way the world has changed since you last had an antenna up.
someone close to you bought a new computer, or new speakers, or a cordless keyboard, or a cordless mouse, or a touch lamp, or a plasma TV, or any number of cheaply made, haphazardly shielded, RF spewing consumer electronics products.
there was a member on here a few years ago who called himself cominatyalive and he had one heck of a time finding and getting rid of his interference.
you might do a search on his user name and read through the two or three threads on this subject.
even if you dont get an answer from them, its good reading and you'll learn what others have tried, and what happened when they tried it.
good luck, and please post back with what you find.
LC