poniedziałek, 30 kwietnia 2012

Selling an Golden Image RC-1000

Finally, I've decided to get some free room at my desktop. I'm selling one of the Amiga RAM expansions I have - the Golden Image RC-1000. Good shape, little yellowed, fully working. ~ 50 Euros OVNO.

Here you can see also how my Amiga 500 looks like now.
Bare motherboard, lies proudly on the desk. Nothing fancy,
waiting to go back to the box OR finishing the 1,5MB ChipRAM trick somehow
(probably NOT, because my Agnus is not fat enough).

sobota, 14 kwietnia 2012

Building an 386 system

Sooo, finally I've put together 386 system that I've got from a guy that was cleaning his garage and getting rid of this machine. First of all I dismantled the whole computer and cleaned the housing. After that the battery on the motherboard was removed, because it was leaky. Electrolyte fortunately haven't done much damage so I've only had to clean the pcb.

After that I've soldered a new battery and put everything together. Although the motherboard has normal ISA slots this housing uses a riser card. This card is plugged into one of the 16 bit ISA slots and offers two 8 bit and three 16 bit ISA slots.

At the current moment the spec of this machine are: 386DX-40 and 16MB RAM. The graphics card is a Trident TVG9000 with 512k of RAM. In the computer you can also see SCSI controller. It's an AHA1540B with 50pin HDD interface (SCSI-1 and SCSI-2 compatible) and with 34pin FDD controller. Also in one of the 8bit slots I've put an I/O controller with serial, paralel and game ports - what a convienient usage of these ports. I still have to connect the floppies and HDD in order to install anything on this machine. After that I have an Scientific Solutions board ready for that PC. It's an 96 digital I/O card. I hope to run some parallel feed digital-to-analog converters on that.

As you can see I've added an second page for my blog called Inventory (see top). I plan to put there all the stuff that I have at home. At the current moment only some of the computers are fully described, the rest is waiting for the description or to be fixed/completed/put together.

czwartek, 12 kwietnia 2012

Box for ammeter

Only a samll update today - a full metal enclosure for the ammeter I'm making at the moment. A nice render for the end of the day:

This will be milled from aluminum. You can see three holes for output, power and sample polarization voltage. There is also a hole for input connector on the other side. For input, output and sample polarization I plan to use BNC connectors, and for the power connector a dedicated three pin military-style connector. I hope to have this machined soon, so I can finish mounting the whole thing.

Also a dedicated sample holder will be milled from non conductive Teflon:

On this image you can see an additional set of clamps with golden needles attached. The needles are used to make an electrical contact with the sample.