Is this a home made data separator?

[lowrybt1]

Found this online. A13 board with one flat edge 34-pin slot connector and one 34-pin IDE (type) connector. Any thoughts on whether the item attached to the A-13 is a data separator? (see attachment)

20181014_165212.jpg (751.77 KiB) Viewed 6927 times

[RedskullDC]

Hi,

Does look like it, yes.

The 74LS123 one shot could certainly be configured to create the necessary pulse, along with the 74LS38 to isolate the clock and data signals.

Cheers,
Leslie

[dave]

I agree, it does look like a data separator. Do you happen to have a link to the site?

[lowrybt1]

Actually, I found it only for $10 and purchased it. I've tested it with a C4PMF without success. On closer inspection, there are a couple of solder joints that are bad. I will fix those soon and try again. I'm surprised that there is no variable resistor for fine-tuning. That's been a component of all other data separator boards I've come across.

[Mark]

The other things that comes to mind is perhaps it is a "disk saver" automatic motor off circuit. My C4P has one that I incorporated years ago to shut off the spindle motor if there is no disk activity. I had it hanging off the A13 board too. Its been too long but I think it monitored head load, and maybe step. It used a large capacitor & one-shot & glue logic to generate a ~30+ second long delay. This worked fine for years until the capacitor failed or was disconnected, and caused me some problems trying to read disks. The drive would shut off mid-disk read.

Back when OSI was new, one of the guys in the OSI users group I belonged to had a floppy that you could see though after weeks/months of sitting in the drive spinning letting the oxide rub off. It was amazing that it still booted!

Cheers,
-Mark