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[WA5YOM]

It seems to work pretty decent on 80....and 40....of course it might not be very efficient....the top hat is certainly something to consider...I would have to design a collar to fit the od of the antenna......then.....drill and tap for each aluminum rod....In the early 70's I had a Swan 500CX mobile with a Hustler 80, 40  and 20 meter bumper mount antenna.....just used the appropriate resonator on top......I still have one of the resonators......stored in the attic...don't remember what band it covered or the power rating...of course, adapting something like that to the existing pole would be a challenge...

[KH6AQ]

An RM80 or RM80S resonator can be attached to the mast using an angle bracket (preferably stainless steel) and one or two hose clamp.

A suitable top hat and coil can be built using 1.5" schedule 40 PVC pipe, #14 THHN wire and six threaded stainless steel spokes. I checked Home Depot online and don't see the small diameter SS threaded rod I purchased a few years ago. Perhaps MFJ would sell you the MFJ-1792 vertical top hat assembly. Page 5 of the instructions describes this as One fiberglass 80 meter loading coil assembly with 7 x 27" spokes . It is your most efficient 80 meter modification.

https://cdn.shopify.com/s/files/1/0289/7782/3843/files/MFJ-1792.pdf?v=1586534137

[WA5YOM]

I assume the pvc and wire is used to make the top mounted loading coil.......it would need the matching network at the base......then it is good for 80 and 40 (I doubt I would use it on 20)....the mfj is 33 ft.....not sure if this needs guys...since the top loading adds wind resistance....but maybe that isn't any worse that having a flag on the pole....

[WA5YOM]

https://static.dxengineering.com/global/images/instructions/dxe-7580-thk.pdf?_gl=1*1wqek4k*_ga*NTU2Njc4MTAwLjE2NzM5MDM2NDc.*_ga_NZB590FMHY*MTY3NDQxOTg2NC4yLjEuMTY3NDQyMDAzOC41OS4wLjA.

Looks like a good top hat kit…less the coil…I like the way it attaches…would have to figure out a method to attach a coil…

[KH6AQ]

Okay, that is not what your antenna needs. It is missing the top loading coil.

Yes, the coil wire is wound on the PVC pipe and the threaded rods attach through holes near the top of the pipe. On my 160 meter vertical the PVC pipe attaches to the aluminum vertical by two #10-32 SS screws sticking out near the top of the vertical. The pipe has two matching holes and it mated to the vertical.

[WA5YOM]

Yeah it needs the coil…which is what I meant by …figuring out where to mount a coil..

[WA5YOM]

So, if that top hat mounts to the side….then maybe the same method of mounting the loading coil below it…..?

[WA5YOM]

Was that you running w6w at 02:43?

[KH6AQ]

Hi, yes that was me and I recognized your call sign. You had one of the bigger signals here on the Big island.

[WA5YOM]

I thought that was you…I started to acknowledge you…but felt like it was not the appropriate time…let your run keep going strong….

[KH6AQ]

Oh lots of ops throw in extras and that's just part of the game. I was running 100 watts to keep the pileup more manageable and to reduce the number of very weak callers.

[WA5YOM]

I am taking off the top section....to see what it will take to modify and add the top hat........so, I am studying the modeling software......
Would like to get 80, 30, 40 at least...160 would be nice....but I haven't tried to model it yet....will be next week before I have time......the top loading coil will need to be determined......the loading coil od may be dependent on what I can find that can be adapted to fit the top section od.........if that make sense......

[WA5YOM]

KH6AQ Worked you again tonight.....strong sig into OKLA...