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I’d definitely take a long drive for it, but for me, there’s an ocean in between. The severe rust seems concentrated on the left side and some surface rust on the front. Hard to know for certain without seeing the entire unit

Thanks for the reference. I was looking to be more precise about the delay. Basically emulating the functions in this chart in the Nov 1976 Maintenance Manual (mostly the right side of the diagram) When the track is close by the delay is essentially zero, as you mentioned. There's actually a...

The present version has the exact same rotational latency as the RK05. This is necessary because the RK05 bus has index and sector pulses and binary sector address signals and the emulator needs to generate those so the controller can react properly. However, the track to track seek time of the...

I’ll be in Amsterdam in April. Maybe I could purchase it and we could arrange a handoff. Will PM you with details

I can check mine this coming weekend. Based on the serial number, it's slightly past half-way through the production run of the 8/L's

I plan to ask just my cost for parts plus whatever amount for shipping. Rather than try to make a profit, I think the fun is to have some of these in use. Plus, when configured as a tester, maybe we can enable the restoration of some real RK05 or Diablo drives. It turned out to be more...

This is definitely possible. There are already pads for the switch wires and LEDs could be removed to expose rather large SMT pads. In a future version of the board it would be possible to add through-hole pads next to the LEDs... there's a lot of extra space in that area. The rocker switches...

Thanks, Tom and Paul. The FPC connectors are quite small and inexpensive, but as we discovered while testing, they are also somewhat fragile. The 0.1" headers will be more robust which could be a benefit for a device that users might disassemble and reassemble. The servo motor has been...

Just a quick update… at the end of last year after a good amount of testing with RK8-E controllers, I updated all of the PCBs: emulator main board, front panel electronics, microSD adapter, M993 clone (paddle card that connects from flat cables to RK05 bus), tester adapter paddle card, and a...

The IC placement of the Plessey PM-837 board looks very similar to the original (M837 photo copied from so-much-stuff.com). I wonder if the schematic of the Plessey board is also very similar, or maybe even identical.

Regarding product quality, we really know nothing about the Chinese connectors (gold plating thickness, plating over what metal, rating and consistency of contact spring force, dimensional tolerances, etc.). In my experience, there are usually some compromises of quality favoring low cost for...

I've never seen one of the ECS connectors but have read discussion in the DEC forum where members have talked about large bulk orders of 100-or-so connectors. My understanding is that the boards can seat deeper in the ECS connectors so they are more stable, without support. Also I believe the...

305blake legitimately sold that exact 8/e system with TU-58 back In November (I happened to recall the linoleum tile floor and white dust😂). The scammers copied his photos and posted them as their own.

I see quite a few on eBay when searching for 24000 uf, but I'm in the US so you might see different search results. Digikey and Mouser have some 24000 uF 63 volt parts by Kemet that might have similar or same dimensions. The capacitors in your photo have a strange color. Is this how they were...

Have to remember that this machine was introduced in 1968, and things were quite primitive back then, compared to how things were done a decade or two or three later. @czunit commented about how he brought up an 8/L, actually two of them...

Rotational latency, yes. The interface signals pretty much require that. I suppose it might be possible to spin the virtual surface faster until the controller decides to read or write a particular sector, but I was too afraid to deviate from the normal operational characteristics. I wanted to...

Currently, there is some granularity of supported bit rates, only 1.44 (RK8-E & RK11-D), 1.545 (RK11-E), and 1.600 Mbps (Xerox Alto) are supported. These have been verified using the RK05 Tester but so far, only the RK8-E properties have been checked using a "real computer".

So, the emulator not performing any controller functions is really the main reason for the present format being what it is, with JSON metadata followed by the disk sector data written on the RK05 platter. Mostly, the JSON metadata describes physical and timing attributes. The new fields being...

hmmm, interesting idea. You're thinking a value that would be unique to determine that a file is different from any other file that's not produced via a direct copy? Could be a hash of the current date, time, and user ID, something like that?

As Vince mentioned, there's an easily buildable Flip Chip tester documented here: https://github.com/G-Wiley/Flip_Chip_Test_System and a zif socket adapter here that fits into the flip chip tester: https://github.com/G-Wiley/IC_Test_Jig I began with the work by Warren Stearns, Michael Thompson...