Using Modern Hard Drives on Old Macs?

[markyb86]

whoa that's going to be one heavy parcel...

ha Yeah it is a little late to be tinkering, but now that you mention it,

wonder if anyone ever hooked up a 73gb to a Plus yet.

if not they have now :-D

 

[Trash80toHP_Mini]

8-o You're insane! :approve: That's 73 GB of SCA Drive, necked down to 8bit fast SCSI II and then pressure gated to something like 1.5 MB/Sec when hosed to a Mac Plus . . .

. . . I LOVE IT!!!!! :lol:

 

[uniserver]

thank the hd smarts seagate designed/sourced, they were serious about SCSI backwards compatibility

one step cooler would be using this hd in a plus

ultimate would be using this hd in a 512ke /w a dove mac snap.

 

[Trash80toHP_Mini]

I've been looking at 68pin adapters for inside the SuperIIsi™ and came up with an interesting solution:

It wouldn't be all that difficult to add termination to an inexpensive adapter, same thing for the 50pin adapters. There's plenty of room on the HDD side of the adapter to solder connections from SIP sockets to the thru-hole solder cones of the 68/50 pin connectors. Soldering directly to the legs of SIP Resistors for the tail end drive of the looped back external SCSI II connector on the Rocket's daughtercard will a more simple solution. At these prices an irreversible termination hack poses no problem . . .

. . . come to think of it, this is approach would be especially nice if termination power is routed to the resistors from the TERM PWR header! }

Whatcha' think, trag? :?:

 

[Trash80toHP_Mini]

Fly in ointment alert for 68pin adapters as linked above: no friggin' TermPWR header . . .





Ah well, that'll be easy to add on, just gotta get the proper inline resistor value from the component between the MOLEX PWR connector and the TPR header on the problem child 50 pin adapters. It's nice that I've got most of that termination hack laid out in Irritator already! [] ]'>

n.b. the striped resistors in the above pics are for the LED circuit, IIRC, has anyone got the spec visible on the problem child?

 

[trag]

It wouldn't be all that difficult to add termination to an, same thing for the 50pin adapters.

. . . come to think of it, this is approach would be especially nice if termination power is routed to the resistors from the TERM PWR header! }

Whatcha' think, trag? :?:

I think your best bet is to carefully examine the adapters from OWC and determine how their termination is connected and what components they're using. Then hack that onto the cheap adapters.

Ultimately, we should be able to come up with a design for Seed Studios, but I think our cheapest source for the SCA, 50-pin SCSI, and power connectors is still going to be a $3 terminationless adapter, and some sweat to desolder the connectors.

 

[Trash80toHP_Mini]

Ultimately, we should be able to come up with a design for Seed Studios, but I think our cheapest source for the SCA, 50-pin SCSI, and power connectors is still going to be a $3 terminationless adapter, and some sweat to desolder the connectors.

I'll doink that layout into AI and see where that goes, but I don't think doing a full seed board would be the way to go.

Replacing the 50 pin header on the $3 adapter with a wire wrap header and soldering a simple terminator PCB to that makes a whole lot more sense to me. A termination adapter board to add to the cheap adapter board (when necessary) would be a LOT easier.

I'll look into it.

 

[uniserver]

yeah come up with a schematic for the cheap Chinese adaptors, isn't it only 8 resistors?

 

[Trash80toHP_Mini]

This circuit board is a LOT more complicated than that, take another look at the pic!

Three removable, 8 pin SIP resistor packs with at least six active lines, that's 18 Data and Signal lines at a guess . . .

. . . one permanently installed 10 pin SIP resistor pack (RP4) between RP1 (under the round tag) and the SCSI connector . . .

. . . my WAG would be that it debounces the unused 8 data lines of Ultra 3 . . .

. . . that'd need to be done even with the sockets for RPs 1-3 unpopulated . . .

. . . which makes me wonder just how effective my standard 50 pin passthru terminator might really be? :O

Right next to the MOLEX connector is what appears to be the obligatory resistor for the LED circuit . . .

. . . but there's something that looks like a diode as well, between the MOLEX connector and the smaller of the three Cap Cans . . .

. . . and what appear to be three bypass type caps as well . . .

. . . and what the heck is that industrial strength Velcro pad doing on there? :?:

 

[Trash80toHP_Mini]

I was hoping that a narrow edgecard board, soldered perpindicular to the pin/solder cones of the IDC50 header would be sufficient. :-/

But that's really no better than my IDC50 passthru connector if proper termination of the unused data channel of the SCA drives is necessary. I'll have to buzz the connections to RP4.

This SCA 80F/IDC 50M Adapters with 27 Lines Active Termination-SCSI U320,U160,SE adapter bears an interesting resemblance to the OWC adapter.

I'm still not crazy about the notion of moving connectors to a Seeed Board, but I may have come up with another approach . . . sooo . . .

http://www.ebay.com/itm/SCA-80-to-50-68-PIN-ULTRA-SCSI-II-III-LVD-SE-ADAPTER-/110629590216

. . . looks exactly like the batch of connectors I bought for using my half height 3.5" SCA drives in the Radius VideoVision StudioArray boxen.

Desoldering the 68 pin connector on one of these boards and installing headers on the SCA side of the PCB would allow a 90mm x 25mm Seeed board to be grafted onto it. Strain relieve the custom termination adapter at the proper height by spacers bolted between it and the convenient holes at the top corners of the adapter. Then solder the (already assembled) termination board to the headers along with jumper wires to the MOLEX soldertail pins for jumper'd termination power . . .



. . . whatcha' think, trag?

 

[uniserver]

http://www.ebay.com/itm/171041290731?ssPageName=STRK:MEBOFFX:IT&_trksid=p3984.m1427.l2649

alright i threw a offer on this lot of 50, i guess i'll see if he accepts it.

i think this foo wants big dolla for his crap.

 

[uniserver]

called up OWC to see if they can get more in, like 50 more…

they are going to email me back, to let me know.

 

[trag]

jt, the exact same seller has another auction:

http://www.ebay.com/itm/111035026224?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

for the same item at 1/4.5 the price.

This makes me suspect that the Ebay seller has been buying them from OWC and reselling them on Ebay. Once the OWC quantity plunged, he had a motivation to substantially raise the Ebay price. But that's all speculation.

Back in the day I was able to buy FWB Jackhammers on UseNet for $50 and they would sell for $150 on Ebay. The Ebay folks never visited UseNet. Those were halcyon days.

 

[Trash80toHP_Mini]

Yah! I shoulda' got a lot more stuff when Shreve clearanced everything out, but it likely would have swirled down the storage room whirlpool.

I saw that auction also, didn't realize it was the same seller. I'm a bit curious about active termination without the use of a controller IC, that's a new one.

I'm still thinking that a Seeeded termination daughtercard for the 8bit/16bit adapter boards is the way to go if we wind up doing a layout. K*I*S*S correct, what do you think of that notion?

I was looking every which way for adapters to do a RAID inside the IIsi, but I'm going with the simple method. Bare bones 68pin adapters and a terminated internal cable.

 

[Trash80toHP_Mini]

It looks like I've found a great loopback cable for the Rocket/SuperIIsi.

If you want to build a cable driver card/extension cable for NuBus, CelGen, this is the kind of cable to use. I can follow up in your thread if you're still thinking about doing that project.

 

[uniserver]

I received my winning auction, these ones are same drives, just 36gb, 10k, still work the same.

just 6 drives in this lot... I am waiting for this 50 or 100 lot, I'm working on getting his price down to $3 a drive. so far he is stuck @ $6.

I told him he is gonna be sitting on them. And so far he has been sitting on them. only time will tell.

 

[uniserver]

Got the SE/30 up and running, In all of its "professionally" installed glory. 36 gb, 10k HD, running 7.1



found an old sca adaptor in a box o stuff, in the garage, this one had built on terminators, it boots right up.

I sold one of these drives to a guy running a Quadra 950.

He happen to have a terminator on the end of his scsi cable, so Term Power jumper had to be removed in order for it to work.

And it does! he is delighted! now he can run his CNC machine with no worries about sourcing a scsi hd for this beast. 73gig, 10k, MacOS 7.6

 

[habibrobert]

Hello everyone.

This has turned into an amazing thread! For the past two weeks I have been reading and re-reading people's postings to get an understand everything. I am having some troubles with my 80 pin HDD being detected by my color classic. So I read up on getting a passive terminator (the kind that plugs back into the external SCSI port). That worked fine. However, I saw some other options on this thread. Some have been talking about using an internal passthrough active connector. So I ordered one along with an extra SCSI adaptor from ebay. That worked, however I seem to be having trouble connecting an external SCSI hard drive. Apple HD SC detects the hard drive, but it never shows up onto my desktop so I can access it. Has anyone had this issue? I have included some photos of the adaptor I bought. I have jumpered the TPR pin and I am not sure if that is what is causing the issue. Also, I don't know what ID pin I should set the internal hard drive to?

Anyone know what I am doing wrong?

Thanks

 

[Trash80toHP_Mini]

If it's your only internal drive, don't set any ID jumpers and it'll be ID 0, which is standard for internal HDDs. It looks like you've got it set for ID 1, which may be conflicting with your external drive. Remove that REM jumper as well.

The only jumper that should be set on that particular adapter would be TPR, unless the CC provides Termination Power?

jt

edit: I see in the post above that the Q950 supplies Termination Power, try your adapter without the TPR jumper.

 

[oldmacs]

Why have all the prices on the SCSI to IDE adaptors skyrocketed on eBay?

I didn't even have the money for them when they were $100 :'(