Hi Rob,
Ok, I can now understand your situation. It all makes good sense but I would like to hear from some other members as to why they have so many machines, could be though, that they are all in the same situation as you.
Anyhow you mentioned that cost was a large factor for some, there is a completely free PC-operated Frequency Generator, complete with list of ailments, explanations and frequencies all in the program. You just select the ailment from the list (hundreds) and the program sets itself up. It is fully automatic or programable, you can add/subtract frequencies, change the run time on any one or more frequencies, change wave types etc.
The only thing that you need is an amplifier and contact or ray tube. It recomends that you use asuitable amplifier that can reach the higher RF mode, it also has a RF clipping mode, starting from 20MHz you can lower it in stages to suit your amplifier. It mentions a suitable list of amplifiers, the GB-4000 is not on the list but the list is so far incomplete.
If you wish to check it out, here is the link.
http://www.heal-me.com.au/
Select FreX from the left-hand pane then scroll down on the right to access the download. I downloaded it last night and played around with it for a while just using my PC speakers as I do not have my GB-4000 yet.
The first thing that you will want to do when you open the program, is go to the button, bottom left of screen "view buffer" and change the setting to clear after selection, everything becomes much easier then.
Kind regards