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Wouldn't you need to know for which computer these are for in order to convert them to binary? But if he knew that, this thread wouldn't exist.

What do you use for a dummy load?

Honestly, you should convert these in to binary and start throwing disassemblers at them. You should try a 6502 disassembler and a Z80 disassembler....

Beautiful work!

I uploaded some drive pictures to http://bitsavers.org/pdf/samsung/floppy/SFD-321B/ They appear to have dropped the shrouded connector when the...

As far as know there are two current IOT1 versions available: The original (IOT1.JED which can still be downloaded from Bob's Spare Time Gimzos...

>>> Don't I just issue the 6410 IOT which takes the contents of ACC and pokes that out on the data bus. Yes, but the signal will only be active...

I've been looking at different Capacitor testers. Can these be used on capacitors in circuit or do they need to be removed? Mike

Have you try to clean the internal adjustment pots for screen size ?. Also if is not that the powersupply in the monitor may have an issue and the...

Thanks Dave, This issue is getting me increasingly confused. I tried to go back to basics and follow the logic by probing the inputs and outputs...

The LOCI-2A has a failure when powered on and the NIXI tubes don't light up. We put the original 1401A NIXI board back in the machine, and all of the...

This is not how you check capacitors. Checking what voltage is across the capacitor does not verify if it's good or not, you need an LCR and/or ESR...

I think that the interrupt issue was on the PDP-12, so that behavior should be common to many of the PDP-8s.

Thanks for the comments on our blogs. We will continue to make the blogs even if we add some videos. From watching a lot of technical videos it...

Booting my TRS-80 into the CP/M disk gives me this message: "TRS-80 Model 4 64k CP/m vers 2.2 (c) (p) 1982 Digital Research Inc. Bios vers 2.22...

IMG 287 is a copy of the Atari Pong video game board IMG 294 is an epson printer board IMG 299 is an early Central Point option board Telemeter...

if you have a logic analyzer i'd take a look at what read commands it is sending. they may interleave the volumes on the physical media it's...

Interesting: mine is marked as DSM 2421 C on the outside and XC-1200U inside, but bought boards, the CRT etc. have Mitsubishi markings.

I used a 4164-15 which works fine. Interestingly it was the first chip in bank 0 that was dead and that killed the whole board. Also not having a RAM...

There are several ways you can do this much easier, than with RS-232C Transfers. I've included my TRS-80 Definitions that are for 22DISK,...

I just build the AT2XT convertor on a perfboard, and here is the circuit diagram. I am using v0.94 of the firmware. However, during post, the AT...

>>> I subsequently reprogrammed the Lattice GAL22V10B successfully to match Bob's original IOT2.jed. The trouble is that you may now have...

That's not the case, at least with 5162/70s and their faithful clones. Because IBM decided to latch the MEMCS16# signal on AEN, the ONLY way to...

I certainly hope not. The raster never really collapses like it would with a FBT failure. Just shakes a tiny bit at the edges

The thing to watch out for with 4164 DRAM is whether they are 128 or 256 cycle refresh devices. 128 cycle DRAM will work in place of 256 cycle...