I've just been having a look at the other three machines, and the outlook is not quite so bleak.
The other N1702 has revealed its cassette deck to be in substatially better overall condition, and this could be attributable the fact that there was a cassette still in the carrier, though its RF/IF-Chroma/Luma panel looks to be U/S - Too much rust and corrosion, with its fuse rattling about loose on the panel, and the fuseholder completely rusted away - Totally gone, no sign of ever being there - vanished!
The N1700s have revealed one clock module which has a (mechanically) working slider switch.. Both have substantially better RF/IF-Chroma/Luma panels.. One has a healthy looking system control panel.. One cassette deck looks like it will go again, but the other seems to have been powered down during a threading, or unthreading cycle, and its mechanical interlocks are preventing me from opening the cassette door, but from what I can see, its deck looks reasonable.
I'm trying to be optimistic, and convince myself that I may just be able to rebuild one N1702, and one N1700.
As for the remaining parts, I would have very serious doubts - but you never know.
Perhaps this thread should have been called "Philips VCR - The fright of the phoenix" -
I will try and get some pictures of these three machines over the next couple of days, but I think it will be a long time before I would want to apply any mains power to them.
Given the nature of the PSU and regulation, I'd surmise that it will an "all or nothing" power up.. In any event, I'm certain nothing will operate until full voltages are available.
The basic power up (normal circumstances) would place the machine in standby mode, with clock illuminated and displaying a flashing 00:00.. The clock and progamme timer can be set and locked without starting the machine.
Starting the machine involves a single press of the power I-O button, at which point the machine will spin up the video head disc and capstan, whilst simultanaeously threading the tape and presenting the drum assembly into the cassette aperture.. If both the head disc and capstan return valid signals to the system control, the machine will remain in this state for about 30 seconds.
If no keys are pressed, the tape unthreads and the system will power down automatically.. If a key is pressed, the machine will enter into which ever mode has been selected.. At this point, it gets more interesting as the transport mechanism now starts to move the tape.. If the tape fails to run, again the machine will power down.
Once we're into this level of operation, it will be the interlocks that will dictate what happens next.