Please help -- SCSI stupidity on my part (?)

[Zac67]

This can't be connected to the SCSI config, at least not directly. Make sure there are no loose metal parts inside the case causing shorts - may have been moved while reconfiguring.

The only thing you can do fundamentally wrong in SCSI is to plug in the cable upside down, but even that can't cause damage when everything accords to standards. Plus the machine would still power up.

Amiga PSUs are dumb ones, i.e. they don't care if anything is attached to them. When they fail to power up (fan spinning?), it's a matter of
- no mains
- PSU broken
- short somewhere (there's a short protection built-in, otherwise some board traces would burn up)

Check out the mains lead - I've had occasions where the contacts were bent/bad. If nothing happens when switching on, switch off again, disconnect the PSU plug from mainboard and try again. If it does power up now, something is short-circuited. (Don't let the PSU run unloaded for lengthy periods.)

Additionally, I think the VLab (Motion?) requires a dedicated HDD and can't share the system disk.

[Zac67]

Usually you can connect the host adapter to any connector of the SCSI cable - provided the bus is terminated at both ends. The BBoAH pics don't look like the VLab provides any means for termination, so you'd have to make sure to terminate the HDD and use a cable terminator behind the VLab.

The Zorro slot shouldn't matter, but depending on what else is hooked up it might. Most of the time you'd put the SCSI adapter in the rightmost slot and add the rest of the boards to the left with decending speed requirements.

[Zac67]

One last point: are you absolutely certain that it's a SCSI port on the card? There are a few cards from other manufacturers (DPS) that have 50pin headers that are not SCSI ports.

Hmm...
amiga.resource.cx lists these features for the VLab Motion:
* optional digital YUV or RGB component transcoders (50 pin feature connector)
* no [...] dedicated hard drives are required
* additional adapter for direct interfacing with the Video Toaster

So the 50pin seems to be the feature connector and NOT SCSI. I figured orb had consulted the manual. Obviously that complicates matters as just about anything might have been killed. :-(

@orb85750: Try to find out which pins carry power or GND and post those here, possibly we can get an estimate of what might be damaged.
These Zorro II slot pins are relevant:
+5V: pins 5 & 6
-5V: pin 8
+12V: pin 10
-12V: pin 20
ground: 1-4, 13, 25, 37, 49, 61, 73, 85, 87-91, 99-100
The GNDs are probably all connected together so any of them will be fine for measuring.

[Zac67]

Does the PSU fan give a slight jerk when turning on (look closely)? That would indicate a short circuit on the 2091 (the PSU's short protection needs a tiny moment to catch).

I think pin 1 is front right, but you can use the GND pins to check.

[Zac67]

orb85750 wrote:

Hmm...
amiga.resource.cx lists these features for the VLab Motion:
* optional digital YUV or RGB component transcoders (50 pin feature connector)
* no [...] dedicated hard drives are required
* additional adapter for direct interfacing with the Video Toaster

So the 50pin seems to be the feature connector and NOT SCSI. I figured orb had consulted the manual. Obviously that complicates matters as just about anything might have been killed. :-(

@orb85750: Try to find out which pins carry power or GND and post those here, possibly we can get an estimate of what might be damaged.
These Zorro II slot pins are relevant:
+5V: pins 5 & 6
-5V: pin 8
+12V: pin 10
-12V: pin 20
ground: 1-4, 13, 25, 37, 49, 61, 73, 85, 87-91, 99-100
The GNDs are probably all connected together so any of them will be fine for measuring.

MY VOLTAGES checked on a couple of Zorro slots:
PIN 5: +5V
PIN 6: 0V to +0.3V
PIN 8: +2V
PIN 10: +5V
PIN 20: +2.5V (some charts leave this pin blank/unknown)

In any event, my situation does not look good, given that only pin #5 is giving the expected voltage.  ANY SUGGESTIONS at this point or should I simply look to buy another Amiga 2000 and hope that most of my expansion boards still work?  I thank you for your input.  (One less working Amiga in this world, thanks to me.)

Well, to make it clear: the pins are numbered like this
1-2
3-4
5-6
7-8
...
99-100

Pins 1-4 are GND, so on the end starting with #1 you'll have two pairs of opposing pins connected together, on the other end it's only two (99-100). Then count to the seventh pair (#13&14) and check which side is GND - that side is that of #1. Provided that service manual I consulted is correct. ;-)

[Zac67]

Just mechanical support...
The case bottom half is one piece running from the back to the front, so there's little point grounding both ends together yet again. ;-)