Archives : May-2016

A recently acquired part of my collection includes what I think is an IBM processor presumably from a large system. The mounting frame is in a 3 x 3 grid. 6 modules are fitted and the other 3 locations are empty. This thing is huge – about 30 inches square. And the weight is around ..

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I’m having a garage sale on Saturday 28 May 2016 to thin out my vintage computer collection a little. Everything put out for sale will be $5 to $20 per item – including large VAX machines. The items available include those shown below (and many more): The items include, for example: About 5 x VAX ..

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This post takes a brief look at the current loop connectors used by DEC. The main focus of this post is the cabling needed to connect a VT220 terminal to a computer (such as a PDP-11/10) using the 20mA current loop interface. DEC’s standard connector DEC used an 8-pin Mate-N-Lok connector for all current-loop cabling ..

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I’ve got a couple of projects on the go that use the PIC18F2550 (or PIC18F2553) microcontrollers. Normally I program PICs in-circuit with a PICkit 3 programmer while debugging my code. While this works great, I also need a way for people to easily field-upgrade my PIC firmware, without the need for a PIC programmer. So ..

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What is it? The DECserver 200 is a “terminal server”. It enables up to 8 terminals to login to various DEC computer systems over an Ethernet link. Back in the day a DECserver it was used to connect terminals and printers to DEC systems.  Typically these were VAX machines, though some PDP-11 systems also supported ..

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I have a few VAX/VMS DECnet machines with node addresses in Area 4. Their full DECnet node addresses are 4.200, 4.202, etc.  When I connect a DECnet machine in Area 33 (full address 33.13) to the same Ethernet segment, each of the Area 4 machines can see each other over DECnet, but the 33.13 machine ..

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