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This shows all but one of the ceiling paperback shelves we built onto the bottom of the 9" BCI joists that support the floor above. When we get the final shelf on as well as the rest of the paperbacks, we'll alphabetize them.


The building, an old church, had 14' ceilings, and so splitting that into two equal spaces minus the floor thickness results in each floor having about 6' 7" of headroom. This puts the base of the joists at a convenient height for retrieving paperback books. Also, this approach provides about 132 additional linear feet of paperback shelf space (6 BCIs, a 1"x12" board creating 2 shelves each 11' long), which leaves the room walls available for other volumes, of which we have plenty.


Eventually - when we get around to it - the library walls will have built-in continuous shelves that go all the way around three walls, 11' each. Right now, we're using prefab shelves to give us somewhere besides the floor to store books. At the time this shot was taken, there were still many hundreds of volumes remaining to move from our old digs. At the back of the room, you can see one of the old windows, which has been sealed off and insulated in preparation for building a wall in front of it that will back the shelves.


Just at the bottom of the image, you can see a Marantz 2325 which serves as the library sound system. This old classic was the ultimate in hi-fi for its day, which was about 1972 or so. In the library, it drives a passive subwoofer and two Linaeum-based surrounds. Sounds fabulous. :-)


The only other non-book-related features of the room are two recliners, a chess table, and a wall with a fishtank and a doorway.


When we're done, there will be about 363 linear feet of bookshelves in the room, between about 231' on the walls (3 walls, 11' each, 7 shelves) and the 132' at the ceiling. This isn't enough for all of our books, but some sections, such as the music and martial arts sections, can go to the spaces devoted to those pursuits (there's a small, but complete, martial arts studio in a building out back that I built by hand, as well as a music studio.) If there is overflow after that, the joists over the entryway may be called into service. You simply can't have too many bookshelves, or books, as far as we're concerned.


I've annotated the image to give an idea of what kind of things are in our library; there are two walls you can't see; there are well populated areas on computer graphics, science, religion and atheism, drawing, do-it-yourself, and so on. Also many books and whole sections haven't made it to the room (or even the building) yet.

Work in progress on the HEX keypad. The generic 6425 push buttons & keytops get BECC self-adhesive vinyl lettering used by modellers. The key switches are mounted on conventional copper strip veroboard, with the IC sockets installed on Protoboard-3U.

My 30+ year old 1802-based computer in a shiny new cabinet, with a keyboard from a Sanders 720 terminal. I have a full write-up on this machine at with photos of the boards. All boards were produced by the Association of Computer Experimenters, a Canadian computer club that published the Ipso Facto newsletter in the 70s and 80s.

ELF2K has swapped its retro switch panel for a HEX keypad developed from STG's circuit schematics

The LED daughter board mounts behind the HEX keypad fascia board, locating each LED adjacent to its corresponding key.

A DIL socket cut down to 2x12 pins provided the offset spacer and connection to the CF/RTC/UART daughterboard

From Josh Bensadon's collection.

Bill Rowe's Olduino marrying an ultrasonic range finder with an 1802! See Bill's site for much more information,

Retro switch panel input option for the ELF2K. The artwork was inkjet printed at 600 dpi on premium photo paper which was then protected by clear self adhesive vinyl film used to cover book jackets.

The HEX keypad front panel with the LED driver daughter board in place. The fascia artwork was inkjet printed on premium glossy photo paper at 600 dpi then protected by clear self-adhesive vinyl film used to cover book jackets.

Netronics ASCii Keyboard with "FastVid" board in its original heavy gauge metal "Big Blue" case. Supplied as a self-assembly kit for use with the Netronics ELFII (RCA COSMAC 1802) and Netronics Explorer kits c1978. Modded by addition of power & shiftlock LED indicators. I really must replace those clumsy brass bolts with something more discrete.

Vintage Computer Festival 10.0

Bill Rowe working on the COSMAC exhibit set up on Friday night.

Netronics RCA Cosmac ELFII with the vintage HL Audio power supply marketed for use with the ELF in the UK at the time c1978.

Memory size: 256 bytes, memory width: 8-bit

Lee Hart's prototype of the 1802 Membership Card "retro-computing in a can"

Josh Bensadon and Lee Hart fielding questions.

Bill Rowe can be seen on the far right by the COSMAC exhibit.

Credit Josh with most of the design, execution, and hardware shown at the COSMAC exhibit, telling the story of RCA's 1802 microprocessor.

This is the lower of the two boards that comprise the membership card. The RCA COSMAC 1802 processor is the big chip on the right. 32K of static RAM is on the left. The remainder of the components are supporting latches and gates. There is a super cap in the lower right corner used to maintain memory when power is disconnected.

Initial startup. Yay... it works. The wayward pink and white wires will eventually connect TP1-1 and TP2-1 from the ELF2K mainboard to the hex keypad. The CF/RTC/UART daughter board is yet to be installed. The 4 digit address and 2 digit data hexadecimal displays are legacy TIL311s.

I wrote a program that I called The COSMAC Doodler for my big COSMAC system, and sold it to Byte as an article in the May 1980 issue. This is something I drew with it, including a face concept for my robot, which I was building at the time.

Another view of my COSMAC Elf. The display is a Hex LED display with Decoder and driver built-in.

In 1980-81 I designed and built a printer for Elf systems called the COSMAC IMP (Inexpensive Matrix Printer.) The thermal print head was a standard item on cash registers at the time. It was touchy to figure out (and it took me most of a year to do that) but it worked beautifully.

Este sujeito é um PECOM 64 de origem sérvia e que utiliza um CDP1802 (sim, um COSMAC!)

My relatively stock COSMAC VIP system, 1977.

ELF's Basic comes to life through Hyperterminal

Top view of the COSMAC IMP.

My COSMAC Elf with its keyboard shown at bottom.

...Well, sort of....! RCA CDP1861 pixie output connected to a VGA LCD monitor using a "Gonbes XVGA Box" display standard converter marketed mainly for legacy industrial CNC units.

I wire-wrapped this board to give original COSMAC ELF I/O to the COSMAC VIP. I later sold an article about it to Creative Computing. "Teaching Your VIP to Speak Elvish" appeared in the October 1979 issue.

STG COSMAC ELF 2000 with 256MB on compact flash, on a Wyse WY-120 display - so much better than a Windows PC terminal program!

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