Save anything from the dump recently?

[SeanB]

Are you talking of the very poor supply rail decoupling, the use of 16 bit ISA when it looks like it was only an 8 bit use, or the QFP devices that were pretty much guaranteed to be running hot and working their way out of the holders.

[Cyberdragon]

I think he's refferring to the fact that despite barely using any of the edge connectors, there are several header connectors. What dummy routed that trace across there...

EDIT: How many layers? Also, what bad decoupling? I see lots of little blue caps, also this is low speed, none of this modern RF speed rubbish.

[TerraHertz]

Are you talking of the very poor supply rail decoupling, the use of 16 bit ISA when it looks like it was only an 8 bit use, or the QFP devices that were pretty much guaranteed to be running hot and working their way out of the holders.

The 'decoupling.' Those "little blue caps" are 0.1uF polyester. *Someone* didn't understand the differences between polyester and ceramic caps, for decoupling. He also didn't know about not feeding TTL outputs into 74HC inputs, and most disastrously, had no idea that one shouldn't pass unbuffered logic outputs (and the logic ground) straight to unshielded cables going off board, to other devices in the upright pokie cabinet. Which players often like to jigger with piezo spark lighters, and whatever.
There were other problems too, but I'd have to dig out my notes. If I even still have them. Oh, one was, the CMOS battery-backed RAM (which holds critical data) wasn't adequately protected from unexpected power downs.

The board went into production and was hopelessly unreliable in the field. This happened because no one did any peer design review, management had no idea, the machine testers didn't bother to act like bastard players, and there weren't any lift motors etc near the testing area.

Redesigning a stupid ISA-based IO board, because someone else did a crappy job, wasn't much fun.  Pic of replacement board. 4-layer, but most importantly fully isolated I/O signals and ground. This one was reliable.

[Cyberdragon]

Much better routing...wait...THAT CHIP IS SMALLER THAN IT'S SOCKET!
DANGER...OCD OVERLOAD! BRAIN =

[SeanB]

VESA bus, and I was thinking for a moment you had used a Ramified Dallas socket for the ROM as well. Must have been around 5 times as fast as the one it replaced as well, and with 16 times the performance to boot, along with having usable memory for both battery backed ( and RTC as well) and ROM store.

I guess this was for controlling a whole row of game machines, so you could have a collective jackpot as well as setting payout probabilities on the fly, plus incorporating payment processing for coin, note and magstripe cards.

[Alex Eisenhut]

I would like to get a nice high-end consumer reel to reel audio tape deck though. One of those things that were out of my reach as a kid/teenager, when they were fashionable.

Think twice about that. I have a Pioneer RT-909 and a TEAC X-3. Reel to reels in general are electromechanical nightmares, and if the heads are finished you have almost no chance to get that fixed on a reasonable budget.

But fashion is cyclical, there's a new café down my street that has a RT-909 as a display piece! I have to go ask the manager if it works, and if he'd want to trade.

I made the mistake of getting mine "repaired". The guy lapped the heads, which is a fatal mistake with Pioneer heads. The sound is unlistenable now.

No to mention all the mechanical traps like the damper arms which need the correct fluid in them to do their job, the cosmetic covers over the rubber rollers, getting a new belt... etc.

Everything has to be just so in order to work.

Now with the weak Canadian dollar the machine I think is worth having is out of reach for me...

[TerraHertz]

VESA bus, and I was thinking for a moment you had used a Ramified Dallas socket for the ROM as well. Must have been around 5 times as fast as the one it replaced as well, and with 16 times the performance to boot, along with having usable memory for both battery backed ( and RTC as well) and ROM store.

I guess this was for controlling a whole row of game machines, so you could have a collective jackpot as well as setting payout probabilities on the fly, plus incorporating payment processing for coin, note and magstripe cards.

Ha ha, fair guess but no. That's not VESA, the extra edge connector is just all the I/O lines. We did a custom motherboard (my co-worker did most of that, the old friend who is now dying of liver cancer.) The board is still 8-bit ISA, though we did have PCI slots.
That backwards S shaped line of components is the ground isolation line, with a gap between the external and internal ground planes. Optos etc straddle it.

[Think twice about that. I have a Pioneer RT-909 and a TEAC X-3. Reel to reels in general are electromechanical nightmares, and if the heads are finished you have almost no chance to get that fixed on a reasonable budget.

 [snip]

No to mention all the mechanical traps like the damper arms which need the correct fluid in them to do their job, the cosmetic covers over the rubber rollers, getting a new belt... etc.

Everything has to be just so in order to work.

Yeah, in general I know they are a pain. Though I've had no experience with specific models. Cassette tape decks and VHS players are bad enough. When I say "I would like to get one" I mean one with the head in good condition, and for which new rubber rollers etc are available.  Ideally with direct motor drive of the reels and capstan, so no rubber belts.
Hence my not having one yet. 

Much better routing...wait...THAT CHIP IS SMALLER THAN IT'S SOCKET!
DANGER...OCD OVERLOAD! BRAIN =

Haven't you seen that done before? EPROM pinouts allow for that - with a jumper to provide Vcc or A12 to one pin, can use 28 or 32 pin EPROMs.

[Rémi]

I saved 3 boards today. 2 x AD581 on them and lots of IC.
Time to use the desoldering wick.