I find this thread somewhat amusing. Sure, you can make an A-77 into a TP machine-but why? If this is the best deck you can afford, then you probably can't afford TP tapes in the first place. The A-77 was a mass consumer deck (think Dynaco ST-70) and it sounds pretty good. Compared to a professional deck, the A-77 looks like a toy and does not have the sound quality you would expect from a professional deck. The stock electronics are noisey as hell. The tape path is so-so. Although Revox made a two track 15 ips version of the A-77, these are much rarer than the 4 track versions commonly sold or the two track versions that only play at 3 3/4 ips and 7 1/2 ips. I am sure you can spend a gazillion dollars on it and improve the tape path, direct wire out the heads to an outboard preamp, etc., but why not just buy a really good deck to start with?? And I say all of this as someone who owned an A-77 and loved it (for awhile) to play back 4 track tapes. That love affair has since ended and the A-77 has found a new home. If you keep an eye out on Ebay, you can get a really nice deck sometimes for cheap that is actually a professional tape deck and built accordingly. You could end up dumping a bunch of money into an A-77 in order to make it play TP tapes and at the end of the day, you stilll have an A-77. Ampex ATR-700 decks go for dirt cheap and they fulfill all of the TP requirements (assuming you get the high-speed version). They have both IEC and NAB equalization built in, balanced inputs and outputs, and decent sounding electronics. This is a professional deck that was designed for recording studio use. People shy away from it because it was actually built by Teac for Ampex (and the Ampex purists will have none of that). The bottom line is that the ATR-700 commonly goes for around $200 in decent shape and you would be hard pressed to buy a good condition working A-77 for that money. This is just one example. My point is, why settle for a so-so consumer deck and dump a bunch of money into it when you can start off with something much nicer for possibly cheaper?
Mark