I received a high-power HF amplifier so I can properly perform some larger-scale Tesla and Cosmic Induction Generator in the near future (and at the upcoming conference). So of course I started tuning things up and seeing how it handles.

Being a fancy high-tech box, it has a lot of automatic interlocks that protect the tubes and electronics from damage. High SWR, overheating, overvoltage, undervoltage, etc.

Unfortunately, it also seems to have a feature ‘gain too low’, that cuts off power when the amplifier is not putting out enough juice. This is a problem for Tesla/HV work, because we’re working with a lot of variables and dynamic components that can easily throw the tuning off. So I am basically unable to tune to match a Tesla transformer due to this, or at least without some modifications……

Immediately, I opened the amp and had a look inside to see what kind of bypass or options I had to mitigate the low-gain cutoff..

After looking at the board and the schematics, I settled on two possible plans-of-action.

1 – The interlock system seems to be driven by a single relay at the end-stage of the amplifier. If I force this relay on, I should be able to force it to transmit in the interlock’ed state and maintain power while tuning+testing.

2 – I looked at the control board and found that it uses a standard PIC32 processor (specifically pic32mx460f512l-80i/pt)

I also found an ICSP programming header, as well as a common serial port in the back of the unit to flash firmware. Using my knowledge of PIC’s, I think I might be able to download and hack the firmware to disable this single interlock while leaving the rest of the system functioning normally….

Over the holiday weekend, the plan is to attempt to dump the current running .bin files for the amplifier, decompile into hex, and attempt to reverse-engineer the section that handles the various interlocks in the unit.

I also grabbed a couple versions of firmware updates to play around with as well, in case the ICSP option falls flat.

I’ll probably also try a quick bypass of the interlock manually to confirm that the system will run OK in this mode.

I was definitely not planning on hacking the firmware of this thing within 24hrs of buying it, but such is life😂

Will report back once I have more data. If *nothing* works then I suppose I can try using a ferrite coupler to help stabilize the input to the Tesla Coils.