From Majordomo@xxx.edu Tue Mar 7 17:28:00 1995 Date: Tue, 7 Mar 95 12:40:37 GMT From: Majordomo@xxx.edu To: wrm@xxx.za Subject: Majordomo file: list 'diy_efi' file 'archive_num_42' -- >From owner-diy_efi Thu Nov 3 18:02:23 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA25805; Thu, 3 Nov 94 18:02:23 GMT Received: from ant.cec.wustl.edu by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo-1.92/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI diy_efi-outgoing id AA25800; Thu, 3 Nov 94 13:02:20 -0500 Received: by ant.cec.wustl.edu (5.0/ECL-A1.27) id AA08422; Thu, 3 Nov 1994 12:02:18 -0600 Date: Thu, 3 Nov 1994 12:02:18 -0600 From: mne1@xxx.edu (Matthew Noel Ettus) Message-Id: <9411031802.AA08422@xxx.edu> To: diy_efi Subject: newbie Content-Length: 159 Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI Hi. I am new to this list. I am the team leader of the Washington University Formula SAE team, and we are considering fuel-injecting out honda cbr600 engine. >From owner-diy_efi Thu Nov 3 20:50:17 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA26519; Thu, 3 Nov 94 20:50:17 GMT Received: from mn.ecn.purdue.edu by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo-1.92/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI diy_efi-outgoing id AA26514; Thu, 3 Nov 94 15:50:12 -0500 Received: from mn.ecn.purdue.edu (armfield@localhost) by mn.ecn.purdue.edu (8.6.9/3.5davy) id PAA14139; Thu, 3 Nov 1994 15:50:08 -0500 Message-Id: <199411032050.PAA14139@xxx.edu> Date: Thu, 3 Nov 1994 15:50:08 -0500 From: Jeffrey S Armfield To: DIY_EFI Subject: Hot Rod Lawn Mowers Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI OK, we've got one of these also. A single cylinder air-cooled L-head Kohler engine with 29 cubic inches displacement. We took a little easier route when it came to fuel injection. We threw money at it. Had Electromotive whip up a one-cylinder version of their TEC-1 EFI unit with fuel and spark control. This setup works GREAT! That is, for our research purposes, it works great. Using GM manifold pressure, coolant temp, and air temp sensors. Mag pickup with a 60-2 tooth wheel for timing information. Heated Bosch EGO sensor and Bosch injector. Injector is P/N 280 150 941. Bosch claims this is a Ford application but no one I know at Ford has ever been able to confirm that. I'm hoping to produce our own engine controller this summer as we implement some novel control algorithm ideas. Oh yea, we've already laid claim to the title "World's Highest Tech Lawn Tractor Engine". Jeff Armfield >From owner-diy_efi Thu Nov 3 20:51:29 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA26526; Thu, 3 Nov 94 20:51:29 GMT Received: from gw1.att.com by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo-1.92/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI diy_efi-outgoing id AA26521; Thu, 3 Nov 94 15:51:25 -0500 Received: from uscbu.ih.att.com by ig1.att.att.com id AA19470; Thu, 3 Nov 94 14:27:20 EST Received: by uscbu.ih.att.com (4.1/EMS-1.0.2 main.cf 1.37 10/5/93 (SMI-4.1/SVR4)) id AA10710; Thu, 3 Nov 94 13:27:59 CST From: Bohdan.L.Bodnar@xxx.com Received: from usgp1.ih.att.com by uscbu.ih.att.com (4.1/EMS-1.0.2 main.cf 1.37 10/5/93 (SMI-4.1/SVR4)) id AA10705; Thu, 3 Nov 94 13:27:57 CST Received: by usgp1.ih.att.com (5.0/EMS-1.1 Sol2) id AA22262; Thu, 3 Nov 1994 13:30:16 +0600 Date: Thu, 3 Nov 1994 13:30:16 +0600 Message-Id: <9411031930.AA22262@xxx.com> Original-From: bohdan@xxx.com (Bohdan L Bodnar) To: DIY_EFI Subject: Re: Oxygen sensors Content-Type: text Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI | How I saw it done in the controller in the 1991 GMC pickup truck | is the O2 chip has an internal voltage divider that places the output | of the O2 sensor at 0.450 volts until it warms up. Once its internal | resistance drops below a certain point, the size of the O2 amplitude | indicates primarily temperature. > ok, so if its cold the output voltage stays between, say, .3V and .6V > for an extended period of time. Once it exceeds these thresholds, we > declare it's hot enough to use. > > If we aren't trying to meat emission standards, I suppose a simple > warmup period is enough. (?) My $0.02 worth... The usual procedure is to (1) monitor coolant temperature and (2) run a watchdog timer. In some systems (e.g., Chrysler's EFI) the computer also monitors something like vehicle speed; this information is used to "diddle" the timer's setting on the fly. If the coolant temperature stays below a certain point for a programmed time, a "stuck cold" fault code will be set (note that most contemporary computers will also monitor the bounds on the coolant temperature and will have fault codes for out-of-bounds conditions) and A DEFAULT value used. A lot of people with scan tools will read the coolant temperature and assume that the computer is seeing this temperature; in fact, the computer is merely outputting the value it is currently using. If the temperature reaches a certain operating point (usually, around 180F) the computer will start varying the a/f ratio and see whether the O2 sensor responds with a *binary* signal (i.e., close to 0 and close to 900 mV) which varies. Modern computers will not only monitor the response, but also, given a mathematical model of the engine, associate a response time window with the varying. Put differently, the computer is looking for a response (O2 sensor output) given an input step function (a rich or lean mixture) and a model of the system. This is why on carbureted engines in closed loop the M/C solenoid's dwell is varying and why on EFI engines the total pulse width of the injectors is varying (on peak-and-hold injectors, the "peak" time is fixed -- around 1.5 ms -- whereas the "hold" part will vary). > John S Gwynne > Gwynne.1@xxx.edu > Regards, Bohdan Bodnar >From owner-diy_efi Thu Nov 3 23:55:58 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA29371; Thu, 3 Nov 94 23:55:58 GMT Received: from shiva.trl.OZ.AU by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo-1.92/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI diy_efi-outgoing id AA29366; Thu, 3 Nov 94 18:55:40 -0500 Received: by shiva.trl.OZ.AU id AA04715 (5.65c/IDA-1.4.4 for DIY_EFI@xxx.edu); Fri, 4 Nov 1994 10:55:25 +1100 From: Craig Pugsley Message-Id: <199411032355.AA04715@xxx.AU> Subject: O2 fouling, EEC V To: DIY_EFI Date: Fri, 4 Nov 1994 10:55:25 +1100 (EST) X-Mailer: ELM [version 2.4 PL20] Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Content-Length: 641 Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI Hi there, Two quick things: i/ Can / does an O2 sensor get fouled by a smoky engine or a two stroke ii/ Does anyone know much about EEC V - is there much info available on it yet? The current model 6 cylinder family car here has EEC V with 'variable intake length' (2 lengths possible) manifold. It is also speed limited to around 110mph which I found interesting, as it probably has enough power to do 140. The reason for this is supposedly to 'reduce the design envelope'-IE brakes don't need to be as big etc. Given that our speed limit is 60-65 mph it's pretty academic anyway. Craig. pugsley@xxx.au >From owner-diy_efi Fri Nov 4 00:56:12 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA29676; Fri, 4 Nov 94 00:56:12 GMT Received: from JULIET.WX.LL.MIT.EDU by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo-1.92/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI diy_efi-outgoing id AA29671; Thu, 3 Nov 94 19:56:10 -0500 Received: from fuelrod ([129.55.57.2]) by juliet.ll.mit.edu id AA25726g; Thu, 3 Nov 94 19:53:05 EST Received: from isotope.reactor by fuelrod (4.1/SMI-4.1) id AA01228; Thu, 3 Nov 94 17:55:41 MST Date: Thu, 3 Nov 94 17:55:41 MST From: jvp%fuelrod@xxx.edu ( Jim Pieronek) Message-Id: <9411040055.AA01228@fuelrod> Received: by isotope.reactor (4.1/SMI-4.1) id AA06468; Thu, 3 Nov 94 17:57:56 MST To: DIY_EFI Subject: O2 fouling, EEC V Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI Craig Pugsley writes: > > ii/ Does anyone know much about EEC V - is there much info available on > it yet? The current model 6 cylinder family car here has EEC V with > 'variable intake length' (2 lengths possible) manifold. It is also > speed limited to around 110mph which I found interesting, as it > probably has enough power to do 140. The reason for this is > supposedly to 'reduce the design envelope'-IE brakes don't need to > be as big etc. Given that our speed limit is 60-65 mph it's > pretty academic anyway. > I worked on engine controls at the Generous Motors Lansing Powertrain Engineering Center several years ago. They limited the speed on the Quad 4 cars to 106 MPH because of the tires. You have to slap on some pretty good (expensive) tires to be able to survive 140 MPH for long. "That'll be $0.02 please", Jim =================================================================== J. V. Pieronek Phone: (505) 243-5822 M.I.T. Lincoln Laboratory FAX: (505) 243-5823 Terminal Radar Development Facility Internet: jvp@xxx.edu Albuquerque, New Mexico >From owner-diy_efi Fri Nov 4 01:55:23 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA29866; Fri, 4 Nov 94 01:55:23 GMT Received: from naitgate.nait.ab.ca by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo-1.92/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI diy_efi-outgoing id AA29861; Thu, 3 Nov 94 20:55:19 -0500 Received: by naitgate.nait.ab.ca (AIX 3.2/UCB 5.64/4.03) id AA26965; Thu, 3 Nov 1994 18:55:54 -0700 Date: Thu, 3 Nov 1994 18:55:53 -0700 (MST) From: Grant Beattie Subject: EFI Books To: DIY_EFI Message-Id: Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI Since my background is more computers than cars, I was wondering if anyone could recommend a good book. Someone mentioned the Bosch Blue book. I think I can get that one from Eric Waiter Associates. Is this book one of the better ones? GB >From owner-diy_efi Fri Nov 4 11:07:18 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA00953; Fri, 4 Nov 94 11:07:18 GMT Received: from kaiwan.kaiwan.com by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo-1.92/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI diy_efi-outgoing id AA00948; Fri, 4 Nov 94 06:07:14 -0500 Received: from kaiwan009.kaiwan.com (1300@xxx.5) with ESMTP id DAA23430 for ; Fri, 4 Nov 1994 03:07:08 -0800 *** KAIWAN Internet Access *** Received: (from patriot@xxx.9) id DAA22720; Fri, 4 Nov 1994 03:07:15 -0800 *** KAIWAN Internet Access *** Date: Fri, 4 Nov 1994 03:07:15 -0800 (PST) From: Nate To: DIY_EFI Subject: Re: Oxygen sensors In-Reply-To: <199411031332.AA16538@xxx.net> Message-Id: Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI On Thu, 3 Nov 1994, Andy Harrah wrote: > When I first got interested in O2 sensors, I went down to the Patent Office > to do some research. Its about 10 miles from me. > > I found an interesting GM patent (no. 4,130,095 Dec. 1978) that describes > how they can tell of the sensors are hot enough to be given reliable data. > The model of the O2 sensor is like a battery. The terminal voltage is a > function of the CO or oxygen content, and the internal resistance is a function > of the temperature. These things are really high impedance devices. GM uses > a clever approach that alternates between taking samples with a high impedance > input, and one that loads down the sensor. How about you wait till after you reset (thus ignition is just turned on) then wait till motor comes up to RPM over 300 RPM, then count the minutes that it is over 300 RPM, and figure it's pretty hot by then? I know it's cheap, but it works for a home brew job. The home brewers would have a monitoring set up like a LCD or something anyway, because we hate idiot lights. Assuming this, one would be able to find a bad sensor problem. I hate adding circuits into something that really don't need to be there. When I'm the one whos got to wire wrap it all together! You would be watching the RPM's for other stuff anyway. GM has it right, because this would also tell you when the sensor was going bad. If you didn't get a reading after a while, then you know it's bad. If you didn't sense this way, then you might think that the thing was idling, well maybe..... Now that I think about this, is there really a reason for this temp measurement? Would make it a bit more accurate on when it went into "full on" mode, but so what... The darn thing is probably wrong in mixture anyway no matter what they do, while it's warming up. Besides, if they want to be so accurate, then why doesn't my car get 70 MPG??? >From owner-diy_efi Fri Nov 4 11:22:19 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA00981; Fri, 4 Nov 94 11:22:19 GMT Received: from kaiwan.kaiwan.com by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo-1.92/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI diy_efi-outgoing id AA00976; Fri, 4 Nov 94 06:22:15 -0500 Received: from kaiwan009.kaiwan.com (1300@xxx.5) with ESMTP id DAA23882 for ; Fri, 4 Nov 1994 03:22:08 -0800 *** KAIWAN Internet Access *** Received: (from patriot@xxx.9) id DAA23078; Fri, 4 Nov 1994 03:22:16 -0800 *** KAIWAN Internet Access *** Date: Fri, 4 Nov 1994 03:22:16 -0800 (PST) From: Nate To: DIY_EFI Subject: Re: Oxygen sensors In-Reply-To: <941103101049.20b6@xxx.gov> Message-Id: Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI Let me clarify... This is on a 1985 Chevy Sprint, made by Suzuki originally. (the car I put a monitor on). It uses the O2 sensor to richen and lean the mixture in a closed loop. THe sensor really works good because I tried leaning and enrichen the mixture manually and it changed quite rapidly! Once it's hot, it reacts very quickly. Not that you would have the computer make rapid changes, I would average it (and it looked like they did too) and slowley change the mixture. I remember when I first started messing with stuff like this, I would forget that the CPU was so fast, and would have to re write my code when I connected it up to the real world. Here's the simple monitoring equipment idea I used... Connect a Radio Shack "bar graph" display to the sensor output (0 to 1V), through a resistor (10K I think) and put a CAP about 33uf on it (this takes out any varances). This gives you a idea of what the sensor is doing. Then conect a LED (1K resistor in series) to the "lean/rich" selenoid, and it will vary as the mixture is leaned out etc.... (you watch the pulse width modulation with your eye). It's interesting to watch it work. Have fun... >From owner-diy_efi Fri Nov 4 13:34:16 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA01619; Fri, 4 Nov 94 13:34:16 GMT Received: from access4.digex.net by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo-1.92/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI diy_efi-outgoing id AA01614; Fri, 4 Nov 94 08:34:13 -0500 Received: by access4.digex.net id AA25773 (5.67b8/IDA-1.5 for DIY_EFI@xxx.edu); Fri, 4 Nov 1994 08:34:11 -0500 From: Andy Harrah Message-Id: <199411041334.AA25773@xxx.net> Subject: Oxygen sensors To: DIY_EFI Date: Fri, 4 Nov 1994 08:34:11 -0500 (EST) X-Mailer: ELM [version 2.4 PL24beta] Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Content-Length: 228 Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI The loading scheme to detect a warm sensor was from the days before they used self-heated sensors. The Chevy manuals claim the sensors will cool off and the system will go open-loop during periods of extended idling. .../Bill >From owner-diy_efi Fri Nov 4 13:59:18 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA01662; Fri, 4 Nov 94 13:59:18 GMT Received: from gold.tc.umn.edu by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo-1.92/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI diy_efi-outgoing id AA01657; Fri, 4 Nov 94 08:59:16 -0500 Received: from dialup-5-84.gw.umn.edu by gold.tc.umn.edu; Fri, 4 Nov 94 07:58:17 -0500 Date: Fri, 4 Nov 94 07:59:02 GMT From: "Matthew Lee Franklin" Message-Id: <17770.fran0054@xxx.edu> X-Minuet-Version: Minuet1.0_Beta_11 X-Popmail-Charset: English To: DIY_EFI Subject: Re: EFI Books Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI On Thu, 3 Nov 1994 18:55:53 -0700 (MST, Grant Beattie wrote: >Since my background is more computers than cars, I was wondering if >anyone could recommend a good book. Someone mentioned the Bosch Blue >book. I think I can get that one from Eric Waiter Associates. Is this >book one of the better ones? >GB BOSCH has a "Red" book, too. It was $38.00 from SAE a couple of years ago. Its title is "Automotive Electric/Electronic Systems". There may be other better books, but this one is pretty good Matthew L. Franklin University of Minnesota Department of Mechanical Engineering 111 Church Street Southeast Minneapolis, MN 55455-0150 Phone: (612)625-4074 FAX: (612)624-1398 Home Phone/FAX: (612)331-3511 >From owner-diy_efi Fri Nov 4 15:48:37 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA02796; Fri, 4 Nov 94 15:48:37 GMT Received: from pine.cse.nau.edu by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo-1.92/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI diy_efi-outgoing id AA02791; Fri, 4 Nov 94 10:48:31 -0500 Received: (from met@xxx.edu; Fri, 4 Nov 1994 08:48:29 -0700 Message-Id: <199411041548.IAA11210@xxx.edu> From: met@xxx.edu (MTN-KAT) Date: Fri, 4 Nov 1994 08:48:29 -0700 X-Mailer: Mail User's Shell (7.2.5 10/14/92) To: diy_efi Subject: Electronics specs questions Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI I don't know diddly about electronics. I'm sitting here looking thru a Digikey catalog trying to figure out which mosfet power transistors and which opto-isolators to use for my project. the mosfets list BVdss, Ip, Idm, Vgs, Rds and PD. From my reading in Practical transistors and Linear IC's book, BVdss is the voltage to trigger the transistor. All of these mosfets are 60V-120V, obviously I'm only running 13.5V max, what am I missing? The opto-isolators list BVCEO(min), the smallest is a 7V with a current transfer ratio of 250%, no specs for on/off time. From my reading a darlington output should boost the current, the catalog doesn't say how much. The isolation voltage is only 3000V for this particular item, some list 5300V would they be better for isolating the engine noise from the electronics? I had ordered some logic level opto-isolators and they came with schmitt trigger outputs, I tried to run these at slow speed 0.1 sec and they just stayed in on mode, the data rate is supposed to be 1.0MHz. Could I have been hooking them up wrong? Is there a cross-reference manual available, I have a listing for some logic level IGBT's, HGTP15N40C1 but Digikey doesn't have any part numbers similar to this. The MOSFETs have a part number, IRF540, once again no similar numbers in the catalog. Could someone help me figure out what I'm missing? Millam >From owner-diy_efi Fri Nov 4 16:05:44 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA02989; Fri, 4 Nov 94 16:05:44 GMT Received: from aztec.co.za by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo-1.92/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI diy_efi-outgoing id AA02983; Fri, 4 Nov 94 11:05:25 -0500 Received: by aztec.co.za (Smail3.1.28.1 #5) id m0r3PgX-000Ke6C; Fri, 4 Nov 94 16:32 EET Date: Fri, 4 Nov 1994 16:32:08 +0200 (SAT) From: Wouter de Waal Subject: PCB / Cad progs To: efi list Message-Id: Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI I found a fairly nice (for shareware) shareware circuit drafting / PCB layout package called PADS. Sits on Simtel. PC based, sorry John :) Anyway, this thing has all the symbols, 68000, 8031, 80x86, TTL, CMOS, etc. It seems easy to add to this as well. Outputs Gerber, Postscript, etc. So : Maybe this should become a semi-standard for capturing and distributing circuits. It's free, seems to work, has less annoying bits than WordPerfect (for what that's worth...) etc. Wouter de Waal PS : My opinion - my boss loves WordPerfect (REALLY!) ÿ