Isolation across the switch boxes

I have 4 switches - 2 antennas, 2 radios and the switches let me chop and change as required. Not great, but it's a little flexible at the moment - especially when I have a vertical that does 6m that I want to do some SWL on, but the antenna is otherwise used for digital - and the radio I use for that doesn't do 6m. 

I have to admit, having the switching has been handy too for testing the antennas if something seems funky... I can usually start by connecting to the spare connectors from my desk and test there. Lazy? Sure.

I come across a video from W2AEW about measuring isolation to ensure that there isn't excessive RF going between multiple radios sharing an antenna via a switch - the isolation on some switches isn't great. 

I use Opek CX-5 switches. Cheap, but functional. 

I won't go into too much detail, though it's something I'll revisit properly at another time. 

I worked off his suggested 40dB minimum as my base line.

These switches are listed as supporting 1000w. 

What I did find:

- Testing isolation between 2 ports on a single switch wasn't great. Up past around 10MHz, it dropped into the mid 30dB range. Not ideal. 

- Testing between the two radio switches. 

    - I have a switch for each antenna. It goes to a switch for that radio. Each radio switch selects which antenna. Effectively an antenna change requires changing two switches. 

    - I decided to test between the two radio switches set to the opposite antennas which is my usual operating scenario. This managed to come in at just on the 40dB borderline. 

    - Having both antennas set to the same radio however, despite it technically not being a direct connection doesn't provide quite so much isolation. Hmm. 

Thoughts?

I'm glad I operate at 10w. This really isn't ideal, but right now it'll do. I think though longer term I need to revise this. Right now while I'm power limited this probably doesn't matter so much. Once I'm starting to push higher power through the coax, I'm not sure I want to risk it.

I'd like an IC-7300 for my primary operation + SSTV and it can live on the dipole given it is by far the better of the antennas.

I'd like to pull the G90 out and keep it for portable operations. It's audio modulation also bugs me around strong signals. It's also a pain having to change the audio inputs.

I'd like to then move the IC706MkIIG to doing digital work, and can use the vertical. The radio of course can do 6m as well, so when I want to play with that, I can just use it. I do like this radio, but the audio certainly isn't a good as newer radios. I also really don't need a waterfall for digital.

So, it would seem in a future state, there will be less switching involved. Looking at the cost of the better switches, replacing with 4 of those is a really decent chunk of that IC-7300.

I really don't need any more excuses to buy another radio. I just need the money. 

And a little more time and motivation to finish studying for my Standard license would be nice. I'm open to donations for all of the above.