My current antenna is a 40m dipole that is installed in my attic. It is 66 feet long. It puts off too much interference for my liking so I am looking for an outdoor installation. My thought was to run it from a tree in the front yard to a pole in the back yard with support on the chimney where the feed line should fall. Is there anything I am overlooking with this setup? Hopefully it gives better performance with less interference. I'm new to HF, so bear with me. MS paint attached.

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Looks ok. If you're talking about transmitted RFI, make sure you have a ferrite choke/balun at the feedpoint, but with the antenna that close it's still a good possibility. If there are specific things that are receiving interference, ferrite chokes might be able to mitigate the problem at the receiving device side.

Looks good, but you still might pick up some noise from household electronics. Some snap-on ferrites on the power cords should reduce it.
Once you get it tuned up, you could sling a 20 meter dipole under it and turn it into a fan dipole.

Also, 40 Meter dipoles can be loaded up on 15 Meters. The SWR might be a little high, but capacitance "hats" can bring it down some: LINK

This is almost identical to the setup I run @ 1kw.  RFI in household electronics is mitigated with ferrite chokes and a WELL grounded station.  Double check your RF exposure limits, just to be sure.

If you can get out like this man can, you will have zero issues being heard.

Here is how I would make a fan dipole. First cut the 40 meter for the lower portion of the 40 meter band. Maybe 7.100 The cut a 20 meter dipole on the same feedpoint above that. Now hang some 1 foot wire about 11 foot out from the center on the 40 meter dipole. Just let them hang down.

Use a good Common Mode Choke at the feedpoint. If using lower power you can just make it out of 13 turns of rg58a coax wound around a 2.4 inch mix 31 torroid.  240-31 torroid.  If you are going to user higher power, best wind it with some RG400.  This is expensive teflon coax, but you can buy short pieces of it on Amazon.

Take a look at the SWR on all 3 bands, and start pruning and looking at all three before cutting or folding back. trim the "hangy down" wires for 15 meter final pruning if needed.  They should all fall below 1.5:1 except maybe the higher end of 40 meters. If you need to operate up there, use the "trim tuner" built into most of the newer rigs. Or whatever you have.

Good Luck   73   James KØUA