Have one with the three modules for 2m / 6m & 70cm I believe was Yaesu's flagship in the late 80s still a sturdy & friendly operating radio.
Said pushes 100w on all HF but true figures are between 109w - 111w.On the modules showing 11watts on all three.
Only downfall is the memory battery's awkward to replace ideal is to add 2x 2032 battery holders at a easy access place to replace them with just four soldering points not rocket science, but will save a lot of time messing around in the future. If your not up to doing the job get someone who is.
So called DC/DC convertor is a small circuit roomed on the dial board.
This circuit makes negative voltages required for VFD display tube and OP AMPs of the tuner.
The circuit represents a small blocking generator. Poorly designed unit in a very tight place what follows to overheat of a small transistor and failure of the whole transceiver.
Repair is possible, but damn troublesome:
One shall remove the board, remove VFD display and then replace bad transistor.
Three years later the situation repeats.
Probably the best transceiver of it't time and measures up with the much newer models.
Great radio!...I have used one of these before. I sure wish I had one that had the 2meter and the 440 boards in them. I miss that radio!...Mark KD4QHG