I would check the power out on a dummy load just to be sure.

Here`s another reason to "read the manual." Canon,and other camera makers have warned the public about buying off brand replacement batteries. Many are cheap,counterfeit batteries that can and will leak or explode when charged. Whenever buying a replacement battery pack,make sure it is the brand name and it comes with a warrenty. The brand name batteries aren`t expensive anyway.

I`d also try running the `718 from an extension cord to another circuit. Years ago I had a loud buzzing ac type noise in my shack. It turned out the outlet for that room was simply damaged from so many plugging in/unplugging over the years. Replaced the outlet and noise was gone. Wish everything was that simple. Do you have a computer on that circuit?

My camera uses Lithiun Ion batteries and they work great. One thing to remember is if you ever put a replacement pack in your pocket,make sure nothing can short the terminals out. Loose change,a pen,etc. They make covers for them but nobody uses them.

I use a 500hz filter in my FT-857D and I`ve found it`s just right for 95% of operating. If I was contesting or field day maybe a 300hz would be necessary. Or if you`ve got two strong stations next to you.

I hate to rant,but my biggest complaint is when I hear,"Too many menues." This is 2013 folks,and unless you own a Drake TR4 or Kenwood TS-520,830S,etc. you will have menues. They are not difficult,just read the manual. Most menu items are set and forget anyway. Since I use power ouput menu selection frequently,I simply leave it on that menu number so when I go into the menu it`s right there. The other one that annoys me is,"You will need the software cd to program it." What`s so difficult about putting 10 repeater frequencies into memory? Unless you`re dealing with 100 memories,that`s different.

I`m curious if the amp ever arced with the old tube. Since this affects all three higher bands,I`m thinking something in the tank area too,like a bad plate choke.

What is your hv for idle and load? Plate current of 300-350ma is too low to make rated output. You can`t get 850 watts out even on 80m with this.

You`re experiencing what propagation is like,and yes that`s typical. 40m is more regional during the day. The fact you heard signals only a few miles away is good,that`s close for 40m,would be easier on 80m. Hearing a nearby state during the day can be difficult at night,as skip can bounce a signal over that area to a much more distant location. A few weeks back I had a bizzare qso on 40m. It was during the day I  called cq,late afternoon,and a station called me from Minneapolis. Keep in mind there was daylight between us both,so a long daylight qso for 40m. Normally I might hear as far as 8 or 9 land in daytime. Working Indiana would be the limit usually. So mother nature can do some strange things for sure. I don`t work much 20m,I will if the higher bands are dead.

I`ve worked cw from the car,but never while driving. That would be difficult for me with a manual transmission! Of course,on an interstate,already in final gear wouldn`t matter unless I had to stop. That`s great having the J-38 on your dash. I`m sure it gets some interesting stares!

I have an AL-80A,which is similar to yours. Depending on your ac mains voltage,(I run mine on 120v) I get rated or near that with 100ma grid,and plate can be anywhere from 400-500ma. I have a voltage drop at my shack cause of a long run. Ideally,with proper voltage the plate current might not go over 400ma. You will,with proper voltage get more than the rated 850 watts out,but I wouldn`t do that. Some say it`s ok to run as much as 150ma grid. I stick to 100,like the manual says. Grid current is the most important thing to worry about,plate current is whatever it is. Values can vary somewhat from band to band also. Your amp might "like" 80m better than 10m.