Activity Stream

The RTX 3080 will be the cherry on the top and it looks like it's going to be a long wait. I upgraded from a 1080 to a RTX 2070 last summer and the...

Fran, I can't determine if you are using two floppy drives or just the 8" Drive. Plus I've not seen or used the FDADAP Interface Board. I'm...

FYI, The Seagate ST11R 8-bit controller supports the ST225R and ST250R drives at 31 sectors.

It's been (nearly) a month since last activity on the thread - how's your wire-wrapping going? PJH

I managed to snag the 5800x off of Newegg for MSRP last night. Now I just need to work out what motherboard I want to pair it with and then get some...

Looks pretty sweet gertk! What type of display is that?

Hi Mike, I have not received the AH5050 yet, it is still in the slow post, but I have the Commodore disk drive & cable. Thank you for the...

But at 3K RPM, rotational latency is about 17 percent higher than a standard 3600 RPM drive. I suppose that you could take a 3600 RPM drive and...

It's usefull in these cases: * Old programs ported from cp/m that do not support directories, i.e. Wordstar and dBASE II Imagine yo have several...

The fan noise is nothing compared to the compressors in a bank of tape drives (CDC 657/659). It was white noise, but LOUD. Our department issued...

No, I haven’t tried this procedure before. I am just thinking out of the box :-)! It is good that you are seeing some coupling though. I do...

Here's the waveform across C468:

Hmm, I thought that I captured the image of each EPROM with it and the Patch ROMs installed on the 4907 memory board, so we wouldn't need the...

Thanks - I may have to give 'em a try.

Just took some startup measurements of PSU voltages and currents, using a current probe. Yes TS117's B is 2.5V more negative than E. I have...

As I recall, the data sheet for the TMS9903 (port3 on the 990/5) said that it supported both character synchronous (e.g. bi-sync) and bit-stuffing...

The zero LED current proves that the supply is running flat out, so it is overloaded, the negative feedback is not operating. Just checking, the...

Ji Jan, have sent you an email directly to see if we can arrange to get the diskette copied.

If not overcurrent on 125V, what circuit could draw excessive current only when the HOT is present? Looks like it could be anything. Not sure if...

You won't physically damage an RLL drive by hooking it to an MFM controller or vice versa. Although now that you mention what model of drive this...

Can you ground the other wires non-intrusively? With the signal generator, the scope and the rest of the mat grounded the only wire on the board that...

I don't know why you would want quiet. My old software partner still does support using SimH. He thinks I am mad to restore old PDP11s and...

That pretty much already happens as soon as you put a DELQA in, since it has a 68000 processor on it. Faster and more capable than most Q-bus...

Was trying to disassemble the complete 4907 firmware, but ran into a problem : The patch rom data is missing... that is because the patch rom...

Be careful! If not you will end up with a fan controller that has more processing power then the PDP-11, Always saw that as the flaw in using a...

Fran, Your YE-DATA YD-174D appears to be very similar to the "YD180_~1.PDF" file I downloaded from Bitsavers (PDF). Page 25 describes the...

The reason that I used a 4K EPROM is because the bin image file is 4K (I believe that it needs the extra space for the added functionality). So, I...