Spare Time Gizmos' Wiki - New pages [en]

Troubleshooting Techniques

2013-04-29T15:46:30Z

Steve Gemeny: Created page with "In response to an request from Management… This page will cover some techniques useful in verifying the correct functioning of SBC6120-RC, stage by stage as it is populated. ..."

In response to an request from Management…

This page will cover some techniques useful in verifying the correct functioning of SBC6120-RC, stage by stage as it is populated. These steps were used to verify the proper operation of the various sections of the SBC6120-RC as it was being assembled and should prove useful to others who;
A) are assembling a system for the first time or,
B) who find it necessary to debug an SBC6120-RC that has failed for some reason.

I hope to be collecting my notes from my January 2013 assembly activities sometime during May 2013.

Email me if I miss this self-imposed deadline and you need the information.

--[[User:Steve Gemeny|Steve Gemeny]] 08:46, 29 April 2013 (PDT)Steve Gemeny

Picture frames

2013-03-05T13:07:44Z

Gizmos: Created page with "| | Steve Gibson has kindly provided these pictures of the picture fr..."

[[File:Steve's Frame 001.jpg|thumb|right|||450px|||]]
[[File:Steve's Frame 002.jpg|thumb|right|||450px|||]]
 
Steve Gibson has kindly provided these pictures of the picture frames he used for his SBC6120. The frames can be ordered from [http://www.larsonjuhl.com/p-1149-510bl.aspx?itemid=1963&CatId=137 Larson Juhl]

Additional parts required to finish the SBC6120

2013-02-12T21:03:57Z

Craig Ruff: Mouser says regulator is obsolete, found some at Newark

{| class="wikitable sortable" style="font-size: 85%; text-align: left; width: auto;"
|+ SBC6120 Parts List
|-
! scope="col" style="font-size: 125%; text-align:left;" class="sortable" |Board
! scope="col" style="font-size: 125%; text-align:left;" class="sortable" |R/D
! scope="col" style="font-size: 125%; text-align:left;" class="unsortable" |P/N
! scope="col" style="font-size: 125%; text-align:right;" class="unsortable" |Quantity
! scope="col" style="font-size: 125%; text-align:center;" class="sortable" |Vendor
! scope="col" style="font-size: 125%; text-align:left;" class="unsortable" |Stock
! scope="col" style="font-size: 125%; text-align:left;" class="unsortable" |Description
|-

! scope="row" style="text-align:left;" | SBC6120 || U1
| 5MHz || align="right" | 1 || align="center" | DigiKey || CTX800-ND || 5MHz DIP8 Oscillator
|-
! scope="row" style="text-align:left;" | || U2,U3
| 74HC373 || align="right" | 1 || align="center" | DigiKey || 296-1591-5-ND || 74HC373
|-
! scope="row" style="text-align:left;" | || U4
| ATF16V8B15PC || align="right" | 1 || align="center" | STG || ||
|-
! scope="row" style="text-align:left;" | || U5
| HD6120-9C || align="right" | 1 || align="center" | STG || || 12 bit microprocessor
|-
! scope="row" style="text-align:left;" | || U6,U7,U8
| HM6208 || align="right" | 1 || align="center" | STG || || 64K x 4 Static RAM
|-
! scope="row" style="text-align:left;" | || U9
| 27C64 || align="right" | 1 || align="center" | STG || || 8K x 8 EPROM
|-
! scope="row" style="text-align:left;" | || U10
| 27C64 || align="right" | 1 || align="center" | STG || || 8K x 8 EPROM
|-
! scope="row" style="text-align:left;" | || U11
| ATF22V10B15PC || align="right" | 1 || align="center" | STG || || CMOS PLD
|-
! scope="row" style="text-align:left;" | || U12
| ATF22V10B15PC || align="right" | 1 || align="center" | STG || || CMOS PLD
|-
! scope="row" style="text-align:left;" | || U13
| 74HC365 || align="right" | 1 || align="center" | DigiKey || 296-8304-5-ND || 74HC365
|-
! scope="row" style="text-align:left;" | || U14
| 74HC245 || align="right" | 1 || align="center" | DigiKey || 296-1584-5-ND || 74HC245
|-
! scope="row" style="text-align:left;" | || U15
| 74HC4040 || align="right" | 1 || align="center" | DigiKey || 296-1568-5-ND || 74HC4040
|-
! scope="row" style="text-align:left;" | || U16
| HD6402 || align="right" | 1 || align="center" | Jameco || 43158 || Dual UART
|-
! scope="row" style="text-align:left;" | || U17
| MAX232 || align="right" | 1 || align="center" | DigiKey || 296-6940-5-ND || Dual RS232 transmitter/receiver
|-
! scope="row" style="text-align:left;" | || U18
| 82C55A-5 || align="right" | 1 || align="center" | DigiKey || CP82C55A-5Z-ND || CMOS PIA
|-
! scope="row" style="text-align:left;" | || U19
| 74HC05 || align="right" | 1 || align="center" | DigiKey || 296-1568-5-ND || 74HC05
|-
! scope="row" style="text-align:left;" | || U20,U22
| 74HC74 || align="right" | 1 || align="center" | DigiKey || 296-1602-5-ND || 74HC74
|-
! scope="row" style="text-align:left;" | || U21
| 74HC175 || align="right" | 1 || align="center" | DigiKey || 296-8257-5-ND || 74HC175
|-
! scope="row" style="text-align:left;" | || U23
| 4.9152MHz || align="right" | 1 || align="center" | DigiKey || CTX763-ND || 4.9152MHz DIP Oscillator
|-
! scope="row" style="text-align:left;" | || U24
| 74HC04 || align="right" | 1 || align="center" | DigiKey || 296-1566-5-ND || 74HC04
|-
! scope="row" style="text-align:left;" | || U99
| DS1233D || align="right" | 1 || align="center" | DigiKey || DS1233D-10+CT-ND || DS1233D EconoReset
|-
! scope="row" style="text-align:left;" | || D1
| 1N4732 || align="right" | 1 || align="center" | DigiKey || 1N4734AFS-ND || 6.0V 500mw DO-41 Zener Diode
|-
! scope="row" style="text-align:left;" | || D2
| Dialight 555-4403 || align="right" | 1 || align="center" | DigiKey || 350-1798-ND || Dialight 555-4403
|-
! scope="row" style="text-align:left;" | || S1
| TP11-SH8-ABE || align="right" | 1 || align="center" | DigiKey || CKN4002-ND
|| Reset Switch
|-
! scope="row" style="text-align:left;" | || C
| 0.1uf Ceramic || align="right" | 22 || align="center" | DigiKey || BC2665CT-ND
||
|-
! scope="row" style="text-align:left;" | || C29,C30,C31,C32
| 1uF 25V tantalum || align="right" | 4 || align="center" | DigiKey || 399-3528-ND
||
|-
! scope="row" style="text-align:left;" | || C37
| 47uf 25V tantalum || align="right" | 1 || align="center" | DigiKey || 718-1176-1-ND
||
|-
! scope="row" style="text-align:left;" | || U5,U16,U18
| Machined 40 Pin DIP Socket || align="right" | 3 || align="center" | DigiKey || ED58406-ND
||
|-
! scope="row" style="text-align:left;" | || U1,U23
| Machined 8 Pin DIP Socket || align="right" | 2 || align="center" | DigiKey || ED58083-ND
||
|-
! scope="row" style="text-align:left;" | || U14,U19,U20,U22
| Machined 14 Pin DIP Socket || align="right" | 4 || align="center" | DigiKey || ED58143-ND
||
|-
! scope="row" style="text-align:left;" | || U13,U15,U17,U21
| Machined 16 Pin DIP Socket || align="right" | 4 || align="center" | DigiKey || ED58163-ND
||
|-
! scope="row" style="text-align:left;" | || U2,U3,U4,U14
| Machined 20 Pin DIP Socket || align="right" | 4 || align="center" | DigiKey || ED58203-ND
||
|-
! scope="row" style="text-align:left;" | || U6,U7,U8,U11,U12
| Machined 24 Pin DIP Socket || align="right" | 5 || align="center" | DigiKey || ED58243-ND
||
|-
! scope="row" style="text-align:left;" | || U9,U10
| Machined 28 Pin DIP Socket || align="right" | 2 || align="center" | DigiKey || ED58283-ND
||
|-
! scope="row" style="text-align:left;" | || J1
| 4 Pin Molex || align="right" | 1 || align="center" | DigiKey || WM6988-ND
||
|-
! scope="row" style="text-align:left;" | || J2
| 40 Pin Right Angle Header || align="right" | 1 || align="center" | DigiKey || A33187-ND
||
|-
! scope="row" style="text-align:left;" | || J3
| 10 Pin Right Angle Header || align="right" | 1 || align="center" | DigiKey || A33179-ND
||
|-
! scope="row" style="text-align:left;" | || J4
| 50 Pin Stacking Header || align="right" | 1 || align="center" | STG ||
|| In FP6120 Partial Kit
|-
! scope="row" style="text-align:left;" | || F1
| 0.5A Picofuse || align="right" | 1 || align="center" | DigiKey || F2339CT-ND
||
|-
! scope="row" style="text-align:left;" | || R
| 10K 5% 1/8W || align="right" | 7 || align="center" | DigiKey || CF18JT10K0CT-ND
||
|-
! scope="row" style="text-align:left;" | || R6
| 4K7 5% || align="right" | 1 || align="center" | DigiKey || CF18JT4K70CT-ND
||
|-
! scope="row" style="text-align:left;" | ||
| IDE/CF Adaptor || align="right" | 1 || align="center" | ||
||
|-
! scope="row" style="text-align:left;" | ||
| IDE Drive Cable || align="right" | 1 || align="center" | ||
||
|-
! scope="row" style="text-align:left;" | ||
| 10 Pin Header to DB9 || align="right" | 1 || align="center" | ||
||
|-
|}

{| class="wikitable sortable" style="font-size: 85%; text-align: left; width: auto;"
|+ FP6120 Parts List
|-
! scope="col" style="font-size: 125%; text-align:left;" class="sortable" |Board
! scope="col" style="font-size: 125%; text-align:left;" class="sortable" |R/D
! scope="col" style="font-size: 125%; text-align:left;" class="unsortable" |P/N
! scope="col" style="font-size: 125%; text-align:right;" class="unsortable" |Quantity
! scope="col" style="font-size: 125%; text-align:center;" class="sortable" |Vendor
! scope="col" style="font-size: 125%; text-align:left;" class="unsortable" |Stock
! scope="col" style="font-size: 125%; text-align:left;" class="unsortable" |Description
|-

! scope="row" style="text-align:left;" | FP6120 || U1,U2
| 74HC373 || align="right" | 2 || align="center" | DigiKey || 296-1591-5-ND || Octal D Tri-State Latch
|-
! scope="row" style="text-align:left;" | || U3,U4
| 74HC174 || align="right" | 2 || align="center" | DigiKey || 296-1579-5-ND || Hex D Flip-Flop
|-
! scope="row" style="text-align:left;" | || U5,U6,U9,U10
| 74HC366 || align="right" | 4 || align="center" | DigiKey || 296-8308-5-ND || Hex Tri-State Inverting Buffer
|-
! scope="row" style="text-align:left;" | || U7
| ATF22V10B15PC || align="right" | 1 || align="center" | STG || || CMOS PLD
|-
! scope="row" style="text-align:left;" | || U8
| 7555 || align="right" | 1 || align="center" | DigiKey || ICM7555IPAZ-ND || CMOS Timer
|-
! scope="row" style="text-align:left;" | || U11
| 74HC74 || align="right" | 1 || align="center" | DigiKey || 296-1602-5-ND || Dual D Flip-Flop
|-
! scope="row" style="text-align:left;" | || U12
| 74HC05 || align="right" | 1 || align="center" | DigiKey || 296-1568-5-ND || Hex Open Drain Inverting Buffer
|-
! scope="row" style="text-align:left;" | || U13
| ATF16V8B15PC || align="right" | 1 || align="center" | STG || || CMOS PLD
|-
! scope="row" style="text-align:left;" | || REG1
| PT78HT205H || align="right" | 1 || align="center" | Newark || 75C7141 || 5V 2A Switching Regulator
|-
! scope="row" style="text-align:left;" | || D1
| 1N5820 || align="right" | 1 || align="center" | DigiKey || 1N5820GOS-ND || 3A 20V Schottky Diode
|-
! scope="row" style="text-align:left;" | || D2
| 1N5339 || align="right" | 1 || align="center" | DigiKey || 1N5339BGOS-ND || Zener Diode 5.6V 5% 5W
|-
! scope="row" style="text-align:left;" | || F1
| 473.003 || align="right" | 1 || align="center" | DigiKey || F2342CT-ND || FUSE PICO SLO-BLO 2A 125V AXIAL
|-
! scope="row" style="text-align:left;" | || R1,R3,R4
| 10K 1% 1/8W || align="right" | 1 || align="center" | DigiKey || RNF18FTD10K0CT-ND || 10.0k 1% resistor
|-
! scope="row" style="text-align:left;" | || R2
| 17.4K 1% 1/8W || align="right" | 1 || align="center" | DigiKey || 17.4KXBK-ND || 14.4k 1% resistor
|-
! scope="row" style="text-align:left;" | || RP1,RP2
| 560 ohm || align="right" | 2 || align="center" | DigiKey || 4610X-1-561LF-ND || 560 ohm 10 Pin SIP (or 4610X-1-222LF-ND 2K2 for White LED)
|-
! scope="row" style="text-align:left;" | || RP3,RP4
| 560 ohm || align="right" | 2 || align="center" | DigiKey || 4608X-1-561LF-ND || 560 ohm 8 Pin SIP (or 4608X-1-222LF-ND 2K2 for White LED)
|-
! scope="row" style="text-align:left;" | || RP5,RP6
| 4K7 ohm || align="right" | 2 || align="center" | DigiKey || 4608X-1-472LF-ND || 4K7 ohm 8 Pin SIP
|-
! scope="row" style="text-align:left;" | || RP7,RP8
| 4K7 ohm || align="right" | 2 || align="center" | DigiKey || 4610X-1-472LF-ND || 4K7 ohm 10 Pin SIP
|-
! scope="row" style="text-align:left;" | || RP7,RP8
| 4K7 ohm || align="right" | 2 || align="center" | DigiKey || 4606X-1-472LF-ND || 4K7 ohm 6 Pin SIP
|-
! scope="row" style="text-align:left;" | || C1
| 1uf Tantalum || align="right" | 1 || align="center" | DigiKey || 478-1835-ND || 1uf 35V Tantalum
|-
! scope="row" style="text-align:left;" | || C2,C7
| Not Fitted || align="right" | 2 || align="center" | || ||
|-
! scope="row" style="text-align:left;" | || C8
| 100uf 25v || align="right" | 1 || align="center" | DigiKey || 399-6102-ND || 100uf 25V Electrolytic
|-
! scope="row" style="text-align:left;" | || C
| 0.1uf Ceramic || align="right" | 12 || align="center" | DigiKey || BC2665CT-ND ||
|-
! scope="row" style="text-align:left;" | || J1,J2
| 50 Pin Stacking Header || align="right" | 2 || align="center" | STG || ||
|-
! scope="row" style="text-align:left;" | || J3
| PCB Jack || align="right" | 1 || align="center" | DigiKey || CP-102AH-ND || 2.1 x 5.5mm PCB Mount Jack
|-
! scope="row" style="text-align:left;" | || J4
| 2 Pin Female Header || align="right" | 1 || align="center" | || ||
|-
! scope="row" style="text-align:left;" | || J5
| 2 Pin Male Header || align="right" | 1 || align="center" | || ||
|-
! scope="row" style="text-align:left;" | || JP1, JP2
| 2 Pin Header || align="right" | 1 || align="center" | DigiKey || S1012EC-40-ND || 40 Pin SIL header - cut as required
|-
! scope="row" style="text-align:left;" | || FB1, FB2
| Ferrite Bead || align="right" | 2 || align="center" | DigiKey || P9820BK-ND ||
|-
! scope="row" style="text-align:left;" | || S1,PLOCK
| SPDT || align="right" | 2 || align="center" | DigiKey || CKN1067-ND || SPDT Tiny Toggle Switch
|-
! scope="row" style="text-align:left;" | || S
| SPDT PCB Panel || align="right" | 13 || align="center" | STG || || ON-NONE-ON
|-
! scope="row" style="text-align:left;" | || S
| SPDT PCB Panel || align="right" | 7 || align="center" | STG || || ON-NONE-MOM
|-
! scope="row" style="text-align:left;" | || S
| 4 POS Rotary || align="right" | 1 || align="center" | Mouser || CK1056 || ON-NONE-MOM
|-
! scope="row" style="text-align:left;" | || KNOB
| Knob || align="right" | 1 || align="center" | Mouser || 8555 ||
|-
! scope="row" style="text-align:left;" | || LED
| LED || align="right" | 28 || align="center" | DigiKey || 754-1264-ND || Red 5mm LED (or 1080-1009-ND White 5mm LED)
|-
! scope="row" style="text-align:left;" | ||
| Swage || align="right" | 20 || align="center" | Mouser || 1560A || 4-40 Swage Standoffs
|-
|}

SBC6120/FP6120 Group Buys

2013-02-12T20:38:13Z

Gizmos: /* Where can I get more information ? */

== What is it ? ==

[[File:SBC6120 (VCFe Model).jpg|thumb||right||450px|||SBC6120 and FP6120 nicely framed]]
The SBC6120 is a replica of a 1960s/70s vintage DEC PDP-8 computer. It uses the Harris HD6120 "PDP-8 on a chip" CPU and started off as a single board computer the size of a 5-1/4" hard disk (and hence the name, "SBC6120"). Everybody wanted a lights and switches front panel, and a couple of years later I designed the FP6120 ("Front Panel 6120") that you see in the photos. The SBC6120 is fully operational and functional without the front panel - this is handy when assembling the kit, because it's possible to assemble and test the SBC6120 before the front panel is finished. The reality is that no one ever wants one without the other, and so the SBC6120 and FP6120 are always sold together as a set.

The HD6120 CPU used in the SBC6120 is the same one used in Digital's DECmate "personal" computers and is fully software compatible with a PDP-8/E. The front panel is fully functional and has the same complement of lights and switches as a real PDP-8/E. It measures 15" by 8-1/2" and is about 3/4ths scale when compared to a real PDP-8. The SBC6120 will run most software written for a PDP-8, including DEC's OS/8 disk operating system. The SBC6120 has an IDE disk interface that can be used with a real drive or (more commonly these days) a CompactFlash card or SSD.

To find out more, read the manuals for the [http://www.sparetimegizmos.com/Downloads/SBC6120.pdf SBC6120] and the [http://www.sparetimegizmos.com/Downloads/FP6120.pdf FP6120].

== Why a group buy ? ==

[[File:Debee and FP6120.jpg|thumb||right||350px|||Debee and the SBC6120]]
Originally Spare Time Gizmos stocked and sold SBC6120 and FP6120 kits as regular items, and many hundreds were sold that way. However some of the parts used are custom made, such as the faceplate, which is laser cut and silk screened, or the LED shadow mask, which is CNC machined. Many other parts, for example the paddle switches, have to be special ordered from the manufacturer even though they are "stock". All these items have minimum order quantities and can only be purchased economically in large batches. As orders for the SBC6120/FP6120 dropped off, the cost of carrying these items in inventory became prohibitive and Spare Time Gizmos stopped stocking the SBC6120/FP6120. The only practical way to sell them now is in batches of at least 25 to 30 units. Several such group buys have been done in the past, and this will be the fourth one.

== What do I get ? ==

The purpose of the group buy is to batch up all the "unobtainium" parts that you simply cannot buy anywhere else. To that end, Spare Time Gizmos will supply a partial kit for the SBC6120 and FP6120 containing[http://www.sparetimegizmos.com/Downloads/SBC6120-FP6120-Combined-Kit-Contents.pdf] -

* The beautiful FP6120 faceplate, silk screened in five colors and laser cut
* SBC6120 bare PC board (four layers, silk screened and solder masked)
* FP6120 bare PC board (two layers, silk screened and solder masked)
* One NOS HD6120 PDP-8 CPU chip
* A set of 20 paddle switches for the FP6120
* A custom machined LED shadow bar for the FP6120
* Three 64Kx4 SRAMs
* Two 27C256 EPROMs pre-programmed with BTS6120
* Five pre-programmed PLDs (three for the SBC6120 and two for the FP6120)
* Two stacking bus connectors used to connect the SBC6120 to the FP6120

'''That's all - the rest of the parts you will need to supply yourself'''. You should expect to spend another $100 to $200 for the remaining PCB mounted components, depending on how well stocked your parts box is. And of course that doesn't include an enclosure, terminal, disk drive or power supply. There is a complete parts list in the back of the [http://www.sparetimegizmos.com/Downloads/SBC6120.pdf SBC6120] and [http://www.sparetimegizmos.com/Downloads/FP6120.pdf FP6120] manuals, and there are also some more current lists, complete with DigiKey and Mouser part numbers, in the files area of the Spare Time Gizmos [http://groups.yahoo.com/group/sparetimegizmos/ Yahoo! Group].

If you prefer, a fully assembled and tested unit is available for an extra charge.

== How do I sign up ? ==

[[File:FP6120 Closeup.jpg|thumb||right||350px|||Closeup of the front panel]]
That's easy - visit our project page on [http://www.kickstarter.com/projects/sparetimegizmos/classic-pdp8-replica Kickstarter] and sign up as a sponsor. A pledge of $599 gets you the partial kit as listed above, and a pledge of $999 gets you an assembled unit ready for framing.

== Where can I get more information ? ==

* Wondering what's going on? Check the Project Updates on the [http://www.kickstarter.com/projects/sparetimegizmos/classic-pdp8-replica Kickstarter]page.

* Have a question? Check the [[Group Buy FAQ]] first.

* There are web pages for both the [http://www.sparetimegizmos.com/Hardware/SBC6120-2.htm SBC6120] and [http://www.sparetimegizmos.com/Hardware/SBC6120-2.htm FP6120].

* There are full manuals, including assembly instructions and parts lists for the [http://www.sparetimegizmos.com/Downloads/SBC6120.pdf SBC6120] and the [http://www.sparetimegizmos.com/Downloads/FP6120.pdf FP6120].

* Steve Gibson has some wonderful [http://www.grc.com/pdp-8/pdp-8.htm pages and videos] that explain both the original PDP-8 as well as the SBC6120 specifically.

* Steve has also provided details of the [[picture frames]] he used for his SBC6120s.

* There is a [http://groups.yahoo.com/group/sparetimegizmos/ Yahoo! Group] for builders of all Spare Time Gizmos kits. You can post your technical questions there. And be sure to browse the group archives too - there are lots of pictures and files related to past SBC6120 builds.

* There is a complete list of the [[additional parts required to finish the SBC6120]], including sources.

Group Buy FAQ

2013-01-28T18:32:12Z

Gizmos:

* I already have a SBC6120 - can't I only buy the front panel?
* I already have a 6120 chip - how much for a kit without one?
* I only need <this part or that one> - how much to buy just that?

Sorry - no custom orders. It takes far too much time and paperwork to make up special orders, pricing and shipping for everyone who wants it. The only items for sale are the ones listed on the [[SBC6120/FP6120 Buy 2013]] page. If you buy a SBC6120/FP6120 kit from me you're more than welcome to part it out and sell whatever bits and pieces you want. My advice to the people who only want this part or that is to get together (advertising on the Spare Time Gizmos Yahoo! group would be a good start) and work out deals privately.

* Can't you ship by UPS, FedEx, DHL, etc ?

Again, sorry, but no. USPS or International Mail is the only shipping option.

SBC6120/FP6120 Buy 2013

2013-01-26T19:02:42Z

Gizmos: /* Where can I get more information ? */

== News, Updates and Status Reports ==

* Looking thru my inventory after the recent SBC6120-RC buy, I see that I have thirty tested, known good, HD6120 CPU chips left on hand and that's left me pondering the question of "what would be a good use for them?" Given that the last group buy for the original was held three years ago, that seems like the obvious candidate. After calling my old suppliers and asking for quotes, I'm convinced that it's still possible to get all the parts necessary to build the original SBC6120/FP6120 combination, including the fancy paddle switches and custom faceplate. --[[User:Gizmos|Gizmos]] 11:24, 26 January 2013 (PST)

== What is it ? ==

The SBC6120 is a replica of a 1960s/70s vintage DEC PDP-8 computer. It uses the Harris HD6120 "PDP-8 on a chip" CPU and started off as a single board computer the size of a 5-1/4" hard disk (and hence the name, "SBC6120"). Everybody wanted a lights and switches front panel, and a couple of years later I designed the FP6120 ("Front Panel 6120") that you see in the photos. The SBC6120 is fully operational and functional without the front panel - this is handy when assembling the kit, because it's possible to assemble and test the SBC6120 before the front panel is finished. The reality is that no one ever wants one without the other, and so the SBC6120 and FP6120 are always sold together as a set.

The HD6120 CPU used in the SBC6120 is the same one used in Digital's DECmate "personal" computers and is fully software compatible with a PDP-8/E. The front panel is fully functional and has the same complement of lights and switches as a real PDP-8/E. It measures 15" by 8-1/2" and is about 3/4ths scale when compared to a real PDP-8. The SBC6120 will run most software written for a PDP-8, including DEC's OS/8 disk operating system. The SBC6120 has an IDE disk interface that can be used with a real drive or (more commonly these days) a CompactFlash card or SSD.

To find out more, read the manuals for the [http://www.sparetimegizmos.com/Downloads/SBC6120.pdf SBC6120] and the [http://www.sparetimegizmos.com/Downloads/FP6120.pdf FP6120].

== Why a group buy ? ==

Originally Spare Time Gizmos stocked and sold SBC6120 and FP6120 kits as regular items, and many hundreds were sold that way. However some of the parts used are custom made, such as the faceplate, which is laser cut and silk screened, or the LED shadow mask, which is CNC machined. Many other parts, for example the paddle switches, have to be special ordered from the manufacturer even though they are "stock". All these items have minimum order quantities and can only be purchased economically in large batches. As orders for the SBC6120/FP6120 dropped off, the cost of carrying these items in inventory became prohibitive and Spare Time Gizmos stopped stocking the SBC6120/FP6120. The only practical way to sell them now is in batches of at least 25 to 30 units. Several such group buys have been done in the past, and this will be the fourth one.

== What do I get ? ==

The purpose of the group buy is to batch up all the "unobtainium" parts that you simply cannot buy anywhere else. To that end, Spare Time Gizmos will supply a partial kit for the SBC6120 and FP6120 containing[http://www.sparetimegizmos.com/Downloads/SBC6120-FP6120-Combined-Kit-Contents.pdf] -

* The beautiful FP6120 faceplate, silk screened in five colors and laser cut
* SBC6120 bare PC board (four layers, silk screened and solder masked)
* FP6120 bare PC board (two layers, silk screened and solder masked)
* One NOS HD6120 PDP-8 CPU chip
* A set of 20 paddle switches for the FP6120
* A custom machined LED shadow bar for the FP6120
* Three 64Kx4 SRAMs
* Two 27C256 EPROMs pre-programmed with BTS6120
* Five pre-programmed PLDs (three for the SBC6120 and two for the FP6120)
* Two stacking bus connectors used to connect the SBC6120 to the FP6120

'''That's all - the rest of the parts you will need to supply yourself'''. You should expect to spend another $100 to $200 for the remaining PCB mounted components, depending on how well stocked your parts box is. And of course that doesn't include an enclosure, terminal, disk drive or power supply. There is a complete parts list in the back of the [http://www.sparetimegizmos.com/Downloads/SBC6120.pdf SBC6120] and [http://www.sparetimegizmos.com/Downloads/FP6120.pdf FP6120] manuals, and there are also some more current lists, complete with DigiKey and Mouser part numbers, in the files area of the Spare Time Gizmos [http://groups.yahoo.com/group/sparetimegizmos/ Yahoo! Group].

== How much does it cost ? ==

'''THE PRICE FOR THIS PARTIAL KIT OF PARTS WILL BE $600.''' Shipping and handling charges to US domestic addresses is $40 for USPS Priority mail with insurance. International shipping to addresses outside the US is $70, once again for Priority mail and insurance. All shipments to California addresses must also pay 8.625% CA sales tax.

== How do I sign up ? ==

[mailto:orders@sparetimegizmos.com Send me an email] and let me know where you live (so I can calculate the shipping and tax) I'll send you a Google Wallet invoice. Pay the invoice with your credit card and Google will place a temporary authorization against your card for the amount of the sale. '''This is not a charge''' and is simply to verify that your card is valid and your credit limit suffient to cover the charge. When I receive enough orders to make the group buy feasible, I'll place orders my my suppliers for the parts.

The lead time for the components is around two to three weeks, and it'll take me about a week to package up the kits after that. It's at this point that Google Wallet will charge your credit card. Depending on how long it takes us to reach critical mass, you can expect a four to six week delay between placing your order and your kit actually being shipped.

'''Remember that your credit card is not charged when you place the order. Your card will not be charged until your kit is actually shipped.'''

== Where can I get more information ? ==

* Wondering what's going on? Check the '''News, Updates and Status''' section at the top of this page.

* Have a question? Check the [[Group Buy FAQ]] first.

* There are web pages for both the [http://www.sparetimegizmos.com/Hardware/SBC6120-2.htm SBC6120] and [http://www.sparetimegizmos.com/Hardware/SBC6120-2.htm FP6120].

* There are full manuals, including assembly instructions and parts lists for the [http://www.sparetimegizmos.com/Downloads/SBC6120.pdf SBC6120] and the [http://www.sparetimegizmos.com/Downloads/FP6120.pdf FP6120].

* Steve Gibson has some wonderful [http://www.grc.com/pdp-8/pdp-8.htm pages and videos] that explain both the original PDP-8 as well as the SBC6120 specifically.

* There is a [http://groups.yahoo.com/group/sparetimegizmos/ Yahoo! Group] for builders of all Spare Time Gizmos kits. You can post your technical questions there. And be sure to browse the group archives too - there are lots of pictures and files related to past SBC6120 builds.

* And lastly you can [mailto:webmaster@sparetimegizmos.com email me directly] for payment and shipping questions. Please don't email me for technical questions - post those to the Yahoo group so that we can all hear what's said and participate. If you haven't already joined this group then you should, and while you're there check out the group archives.

Attaching the Decal

2012-12-19T01:17:38Z

Gizmos:

Attaching the decal to the faceplate can be tricky, but here's one procedure for doing it, courtesy of Jim Loos.
 

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[[File:Decal1.jpg|thumb||right||200px|||Step 1]]
* Separate the backing sheet from the decal near the center in order to insert a scissors between the backing sheet and the decal.
 
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[[File:Decal2.jpg|thumb||right||200px|||Step 2]]
* With a scissors, cut the backing sheet into two halves being careful not to cut the decal.
 
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[[File:Decal3.jpg|thumb||right||200px|||Step 3]]
* With the backing sheet still in place, position the decal on the faceplate. Hold the faceplate with the decal up to a strong light so that the light shines through the decal and the holes in the faceplate. Position the decal on the faceplate by aligning the "crosses" on the decal that mark the locations for the LEDs and switches with center of the holes on the faceplate.
 
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[[File:Decal4.jpg|thumb||right||200px|||Step 4]]
* Once the decal is in proper position on the faceplate, clamp one half of the decal to the faceplate to prevent movement of the decal.
 
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[[File:Decal5.jpg|thumb||right||200px|||Step 5]]
* Starting from the center of the decal,remove the backing sheet from the unclamped half of the decal and, starting at the center, adhere that half of the decal to the faceplate smoothing out the decal from the center toward the end.
 
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[[File:Decal6.jpg|thumb||right||200px|||Step 6]]
* Again starting from the center of the decal, remove the remaining half of the backing sheet and adhere the remaining half of the decal to the faceplate smoothing out the decal from the center toward the end.
 
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[[File:Decal7.jpg|thumb||right||200px|||Step 7]]
* Using the holes in the faceplate as a guide, cut the holes for the LEDs and switches in the decal. Use an Xacto knife with a new blade!.
 

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When you have finished this section, proceed to [[Final Assembly and Checkout]].

Drawings, Schematics and Firmware

2012-11-22T01:00:29Z

Gizmos: /* Kit Contents */

== Drawings ==
* [http://www.sparetimegizmos.com/Downloads/SBC6120-RC2_Schematic.pdf SBC6120-RC2 Complete Schematic]
* [http://www.sparetimegizmos.com/Downloads/SBC6120-RC2_Mechanical.pdf SBC6120-RC2 Mechanical Drawing]

== Kit Contents ==
If you'd like to know exactly what is and is not included in each kit, then the following documents list every single item.
* [http://www.sparetimegizmos.com/Downloads/SBC6120-RC2_FK_(with_VT6).pdf Contents of the SBC6120-RC2 full kit (VT6 version)]
* [http://www.sparetimegizmos.com/Downloads/SBC6120-RC2_FK_(no_VT6).pdf Contents of the SBC6120-RC2 full kit (without VT6)]
* [http://www.sparetimegizmos.com/Downloads/SBC6120-RC2_PK.pdf Contents of the SBC6120-RC2 partial kit]
* [http://www.sparetimegizmos.com/Downloads/VT6-FK%20(RC2).pdf Contents of the VT6 full kit]

== Manuals ==
There are manuals specific to the -RC version; only this Wiki document. However, except for the differences listed in [[Overview]], the SBC6120-RC is functionally identical to the original SBC6120. THe -RC uses the same firmware, has the same ROM monitor commands, runs OS/8 and uses the same OS/8 device drivers, and has the same switches and lights on the front panel. For more information about the SBC6120-RC please read the SBC6120 manuals.
* [http://www.sparetimegizmos.com/Downloads/SBC6120.pdf SBC6120 User's Guide]
* [http://www.sparetimegizmos.com/Downloads/FP6120.pdf FP6120 User's Guide]

== PLD Files ==

== Firmware ==