So far, I did the following:
1. After contacting the seller and obtaining his permission, I removed the top to check the fuse and unfortunately, this was not the problem.
2. I then removed the fuse and used needle-nose pliars to bridge the gap, still the unit would not power up. (There is power at the fuse contacts.)
3. I further checked the unit for obvious shipping related mishaps (i.e., dislodged connections, internal damage, etc.,) and could not find anything obviously wrong. The unit is very clean, internally and externally and nothing seems amiss, at least visually...
4. I "smelled" for tell-tale signs of electrical issues and this too yielded no results. Often than not, when something burns-up within such a device,
the smell can be felt for a long time.
5. I called Yamaha USA and endured a 40+ minutes of hold! I had to hang up when I received an incoming call... I had called Yamaha USA in the off chance that maybe one of their techs would have an idea; that perhaps there is something common with these units that lead to such no-powering issues.
6. I called a local authorized Yamaha dealer/service center and asked them for their opinion. They said that it will cost $55.00 to trouble-shoot the unit and if any repairs are needed (and the repairs are performed at this particular service center,) they will then apply that amount to overall repair costs.
7. The seller stated that he is willing to issue a refund (he does seem to want to be helpful in this matter) and that he has no idea what happened to the unit.
8. I offered for the seller to pay for the bench-testing with no further responsibility on his part (this would come out of the funds which I have already paid him and he would keep the difference.) I am still hoping in my heart that because of the very clean condition of the unit and no obvious signs of 'abuse' or electrical mishap that repairs needed will not be very high. In the worse case scenario, I would sell the well preserved (hinged) remote and the owners manual to help defray my loss. The unit would simply get put aside as a "parts" unit, in the chance that I get another DSP A1 (albeit a functional one!)
I know many folks feel that this unit is far too old to put too much of an effort; but, I have wanted one for a very long time and I have a number of older Yamaha DSP units (few DSP A1000's and a DSP 3090) which I like very much (and the DSP-A1 is decidedly better than the other two...) If I can get this unit to function, it would be lots of fun to explore all the settings, etc. The unit can also support twin center-channel speakers, R/L main speakers, two front-effect speakers and two rear-effect speakers and can accomodate subwoofers in the following fashion: one single sub, or two front subs, or two subs with one front/one rear configuration. While not THX certified, it is able to emulate THX-like settings and offers DTS (and AC3) decoding, in addition to the old Dolby pro-logic, etc., surround modes. It is a well-built, tank-like device (though unfortunately, even well-built tanks fail, time-to-time...)
I am still stymied and hope against hope that someone who has specific experience/knowledge regarding this unit will stumble upon this post with the "winning" answer...
Thank you all for the advices thus far given.