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The Digital Ultimate Workstation 533au2 |
Telebyte 65A RS232 Converterby billdeg Total messages in this thread: 6 Updated: [ Repairs ] 05/07/2015  I modified my Altair 680 for 110b, no Baudout, 1 stop bit (see notes about stop bits below). I tested my work by connecting the Altair to a DEC VT102 terminal. Comms are slow but they work enough to get to the ROM monitor prompt and enter commands. Now I know the system works well enough at 110 baud to continue. Note in the photo next to the Altair is a Multi-Tech Systems MT25 EIA-CCITT Breakout / Monitor tester. This device allows me to see what signals are being sent through the serial cable. Click image for larger view.
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MITS 8800b Turnkey Restoration (#3)by billdeg Total messages in this thread: 3 Updated: [ Restoration Complete ] 04/30/2015  Started Pertec / MITS Altair 8800b Turnkey system restore project. After doing an initial power test I disassembled the unit for cleaning. Click image for larger view.
 The system itself works pretty well, with 48K RAM. The only functional issue remaining is the front panel. I cannot reset nor start the system using the switches. I removed the front panel card by desoldering the switch posts connected to the rear of the card from the front of the chassis so I could slide the card out. I also desolder">... [ read more ]
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Vintage Joystick Kitby billdeg Total messages in this thread: 1  A game controller from the mid 1970's that was built from a kit. Designs for these kits were published in magazines like Radio Electronics and Popular Electronics.
Looking for the source of the kit for this joystick. If you can provide, please contact me. It looks a lot like the Cromemco joystick, but not exactly.">... [ read more ]
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VCF East 10by billdeg Total messages in this thread: 1  Dave Gesswein powering up the R.E.S.I.S.T.O.R.S. historic PDP-8 computer for the first time in 40 years. A magnificent restoration achievement.
 My pick for best exhibit of the show was Doug Crawford's comprehensive VISICALC, with an impressive display of systems running VISICALC, plus a spreadsheet program he wrote for the RCA ELF.
 Mike Loewen's TRS 80 Model 4 exhibit featured a unit with a hi-res display.
 Dave McGuire's fabulous Digital Pavilion was a smorgasbord of DEC goodness that filled a truck.
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IMSAI 8080 / Thinkertoys Backplane projby billdeg Total messages in this thread: 4 Updated: [ Progress on Imsai 8080 ] 01/31/2010 Project Update: 1. Replaced tantalum capacitors c15, c16, c17, c18 2. Applied power. MC78M12CT (on the schematic it's IC4) started to smoke. Updated pics: New Board pics (have 4/20 file date) power supply pics (have 4/20 file date) One of two things is going on... 1) The IC's are dry/brittle and need to be replaced, the 4 new tantalum capacitors did not smoke after being replaced, it was simply the MC78M12CT (IC4) turn. 2) There is an issue with the power, and that's what's blowing out the ic's. ">... [ read more ] |
DEC Pictures - PDP, VAX, Alpha Picsby billdeg Total messages in this thread: 1  Two Digital PDP 11/40 computers. Both are housed in 72" cabinets The left cabinet contains a standard front panel and on the right stands a PDP 11/40 "industrial11" type.
Picked up a few new restoration projects for me and some friends including a PDP 11/40 "industrial 11" and regular PDP 11/40.
Other items include some Altair 8800b-T unit with drives, two Alpha Servers, two VAX Servers, two PDP 11/34's, two PDP 11/44's, and related parts and peripherals. I will create separate threads for each as they're restored.
Pictures">... [ read more ]
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PDP 11/40 M7656 Serial Commsby billdeg Total messages in this thread: 3 Updated: [ Downloading programs via serial card ] 07/18/2015 Now that the core system is running again I can turn my attention to adding a display and disk drives to the system. I have a M7856 10 F-C (RS232 WITH 19.2 OPTION?) i.e. serial card and few terminals including a vt52 a LA36 Instructions for booting the PDP 11/40 using RL02 drives http://www.pdp-1...sk/rl-info.html Next - I will replace one of the grant continuity cards and put in a M7762 (RL02 controller) in its place and attempt to boot from RL02 using M9312 ROM boot terminator card with RL02 ROM chip installed. I had a hopefully still working RL02 (01) and I bought a second drive from Ian last year (02). I have 10 or so RL02 packs, at least one should be a RT11 boot disk.">... [ read more ] |
Altair 8800B Restorationby billdeg Total messages in this thread: 7 Updated: [ VR2 cap replacement no improvement ] 03/08/2015 The subject of this thread is to document the restoration of a previously-working Altair 8800B, which I accidentally shorted by inserting a RAM card with the power on (oops). After probing voltages and looking for A/C ripple, the general consensus of the MARCH workshop team was to open up the front panel to check for blown voltage resistors. The processor card checked out, but I could not examine memory locations or deposit memory. The front panel could not lock onto a location in memory, the front panel is largely un-responsive to toggled input.">... [ read more ] |
Live long and prosper, Spock |
Intellec MON 80 Monitor HEX Dumpby billdeg Total messages in this thread: 5 Updated: [ Intel imm 6-26 PROM Memory Module ] 02/25/2015  Intel Intellec/8 MON 80 on 8 1702A ePROMs starting from address 3800H. Each 1702A has a sticker that reads MON 80 3800 (through ... 3F00) v. 3.0. Click image for larger view.
This set of 8 1702A ePROMs is installed in the bottom row of an Intel prom memory module imm 6-26. The IMM 6-26 had been around since the original Intellec/4, but I found references to this card in later Intellec system models for the 4040, 8008, 8080. I read that the 4040 version used 4 1702s, and the 8080 version used 16. My board has 8 1702's thus it could be argued that this is a ROM set for the 8008 (loose logic?) On the other hand, the label print style on the proms is similar to images I have seen of the MON 40 f">... [ read more ]
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1966 Honeywell u-COMP DDP-516by billdeg Total messages in this thread: 1  Pictured is the cover from Honeywell's sales brochure of the u-COMP DDP-516 "...third generation general purpose digital computer...". The DDP-615 was a 16-bit word minicomputer expandable to 32K Core RAM memory. Machine I/O was done through the front panel switches and ASR 33 (or 35) Teletype. The DDP-516 was program-compatible with the DDP-116 and ran things like ASA FORTRAN IV.
Brochure">... [ read more ]
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Digital PDP-9 The Serious Computerby billdeg Total messages in this thread: 1 
Cover of the November 1967 Digital PDP-9 Sales Brochure. Sigh. Click image for larger view. ">... [ read more ]
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Digital PDP11 late 1969 early 1970by billdeg Total messages in this thread: 1  The Cover of the Jan/Feb 1970 Digital PDP11 sales brochure.
There is a popular misconception that the PDP11/20 was the first PDP 11 and that the 11/10 was introduced later, with the 11/05 and 11/40. In fact, there was a little-known "rev 1" PDP11/10 and this model was sold simultaneously with the 11/20 when the PDP11 product line was introduced in 1969. This first PDP11/10 was a turnkey unit that could be used as a process control system. A few years later a "rev 2" 11/10 was produced, this time more or less interchangeable with the new PDP11/05. This is the 11/10 most of us know.
PDP 11 Price list December 15, 1969
PDP 11 Sales Brochure (Jan/Feb 1970)
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Teletype Model 15by billdeg Total messages in this thread: 3 Updated: [ Threads with Comments about Photo ] 01/11/2015 Caption contest Avert your eyes before it's too late! "Ms. Amateur Radio 73 November 1976"  Click thumbnail to download larger image - suitable as a desktop background.
Actually, this photo was taken more than ten years earlier. Amongst photos of old teletypes in an article titled "Thirty Years of Ham RTTY", the photo above appears on page 112. What kind of bet did this lady lose? There is a story here. Perhaps you'd like to share your comments...">... [ read more ]
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