Hi
I would like to get some facts so that I can make a choice between the 2 systems in the title. preferably from Aussi users. I know the electraX have colored wire diagrams and component locater actual colored photos plus its user friendly GUI.
I know pico enjoys more support than the earlier brand. any comments are appreciated.

thanks
Sam

Sam,

Good to see you are doing your homework first.   ;)

I looked at the web site for Electrajet.  It appears to be a four channel PC based scope but there were no specs there I could find.  It also appears that the web site has not been updated in about four years.

You would at least have to know the max ADC speed and the record length (buffer size) to make any meaningful comparison.

If the manufacturer can provide you with these specs then you can use this tool:

http://www.autonerdz.com/java/SampleRateCalculator.html

to gage it's performance capabilities.  If they cannot, then they either don't know the specs or are ashamed of them.  Neither is good and you then know what to do.

You will also find a performance chart I prepared for the Pico 3000 series automotive scopes in this s thread:

http://www.autonerdz.com/cgi/yabb2/YaBB.pl?num=1213458091

here is more info about the electraXXX scope
please note the file attached first then read the notes below;

Note:

1. Has a startup peak of 8 Amps
3. If multi Channels are used this figure encompases multi Channels
4. Per Channel
5. Dependent on the PC and Screen used.
6. Also free Runs without a trigger
7. Limited by the number of channels selected. 1 Ch only below 500us, 2 ch only below 1 ms.
8. Option currently not available

---

Sam,

Did you read thru this: http://www.autonerdz.com/picoquad.htm

Cheers
Joe
;)

from the info above it appears that electrXXX is better than pico 3223 but worse than 3423 when comparing the important points as stated by the Calculator. one may ask, how ofter one could need the "resolution" offered by the 3423?

Sam,


Quote:

it appears that electrXXX is better than pico 3223 but worse than 3423 when comparing the important points as stated by the Calculator.

Not sure how you are arriving at that conclusion.  The Electajet would just be a small dot in the rear view mirror up against any PicoScope, even the now obsolete 212/3 parallel port models with a 32K sample buffer (16K per channel) and 3MHz ADC.

Comparing to the 3000 series...using the 2048 sample buffer and 2MHz max ADC speed listed for the Elecrajet with a one second capture time, the Pico 3223 or 3423 would be 683 times faster  :o

IMHO, the Electajet would not be up to the task with today's vehicles.  Just look at the com port.  It uses a parallel port like the old Pico 212 series.  Good luck even finding a PC that has a parallel port anymore.  Parallel port speed is so slow too compared to USB 2.0.  This is old technology.

As for whether you need the kind of power offered by Pico, these forums are full of examples.

http://www.autonerdz.com/cgi/yabb2/YaBB.pl?num=1193262243

In automotive use, it is best to use long time bases to capture a lot of seamless data.  Pico enables you to do this like no other scope, maintaining robust sample rates so that no detail is lost.

Sam, I had a lot of questions too. With all due respect Sir, get some duct tape and tape the lips. Then watch Autonerdz #1 CD.  I feel the same way. This is the best support system and information on Planet Earth.  If in doubt watch it again. Tom is unbelievable.  PS: pull the tape off fast and it will only hurt a little.

Randy Acevedo

Tom Roberts wrote on Jan 21^st, 2009 at 6:34pm:

Sam, Quote: it appears that electrXXX is better than pico 3223 but worse than 3423 when comparing the important points as stated by the Calculator. Not sure how you are arriving at that conclusion.  ...

I used the online java Calculator and entered the data as indicated by the demo.
Samples "buffer size" 128K
the next number is left at 500 as indicated by the demo
the next number is set to 2MHz
hit calculate,
Actual Sample Rate: 250KHZ
Time between samples: 4us
Samples on Screen: 125000

Randy Acevedo wrote on Jan 21^st, 2009 at 7:02pm:

Sam, I had a lot of questions too. With all due respect Sir, get some duct tape and tape the lips. Then watch Autonerdz #1 CD.  I feel the same way. This is the best support system and information on Planet Earth.  If in doubt watch it again. Tom is unbelievable.  PS: pull the tape off fast and it will only hurt a little. Randy Acevedo

Dear Mr. Acevedo
Does #1 CD present a compression between the items listed in the title of this thread?
if so and you watched many times, please inform us.

No one here questioned the superiority of support system nor the integrity of neither the information or Tom’s believability, this thread is not meant to be a religious war. Your rights to make it so is respected but your decision not to is most appreciated.

As to YOUR duct tape solution, we here at down under avoid tapping things, instead, we use permanent plugs, thus issues are considered more than once before a solution is offered ;)

Sam, Sorry you did not understand me. Have a good day.

Randy

I am not favoring electraspec/jet over pico, I am only examining the facts, and so far pico does have an advantage in some things and electraSpec/Jet has advantage in other areas.
Picoscope appears to be superior in capture and display.
Electraspec/Jet appears to include colored wiring diagrams, actual color pictures of component “locator” and isolated component circuit in an easy to access way. "Hybrid solution".

So my take on this is to stick with the picoScope for its dedication to being a scope and get an extra package “ALLDATA as suggested” to cover some of the technical information.

Sam,


Quote:

Samples "buffer size" 128K

I see 2048


Quote:

the next number is left at 500 as indicated by the demo

500 what?  

You would not leave that at anything.  You would enter the desired capture time in there to compare performance at different capture times.


Quote:

the next number is set to 2MHz

Correct.

So, Place 2048 in the buffer size and 2MHz in max sample rate.

Then enter various capture times and compare with the Pico performance chart one channel use column.  This is because the Electajet results are most likely for one channel use.  It does not say there in an ADC for each channel so the 2MHz would be divided by the number of channels in use.

Randy was just joking around.  On second thought maybe he actually did put tape on his face.   [smiley=lolk.gif]

I'm certain he meant no offense.  

Hello Sam1 and welcome if it has not been said before.  I just browsed through this post and noticed the Electra scope is using a parralel port connection and requires an external power supply.  A more comparable pico technology scope would be the 212 series.  They also use parrallel port and extenal power supply.  The self powered usb version is much more convenient.  I have 212-3 and a 3223 so I know  :)

A couple of other thoughts beyond just sampling there are two versions of pico software available.  Pico 5 and pico 6 each is very capable with pico 6 having some very impressive abilities.  Pico recently added advanced triggers as well to pico scope 6.  They did take away the merge feature (a favorite of mine) but I feel the other abilities make it worthwile.

Here is a couple of videos showing the pico scope 6 in use

http://www.youtube.com/watch?v=ELBWsQC6G3I

http://www.youtube.com/watch?v=-ZDOkjUfU2c

Also here is  video clip I made illustrating sample rate.  The pico is adjustable and some of the presets are on the low side.  So it is something to be aware of.

http://www.youtube.com/watch?v=YJEbhELLJQY

One other not an information database is nice to have in the US we have Snap On platforms that have good databases but like anything there can be errors there.  An excellent combination here is a pico and a heritage vantage.  I am not sure if you have similar there but it could be a good addtion.

If you have any other questions feel free.  I am no expert on the specs but I have used the pico scopes for a few years now.

Sam

Sam1,

Some comments (my own $0.02 based on my personal experience):

- I'm not sure how much the Electrajet costs... but the Pico Quad kit from Autonerdz comes with everything you need to immediately get waveforms from any part of your vehicle or most other electronics... you pretty much don't need to buy anything else... the Autonerdz version of this kit contains extras over the Pico company's version of the kit... even if the Pico Quad kit costs more (which I don't know if it does), it is well worth it.

- Autonerdz provides the best support I have seen anyway... Autonerdz even supports me (a hobbyist car wannabe)... Tom has helped me with a few issues with one of my laptops, and the forum members have guided me on interpreting some of my ignition waveforms... if car repair is your career, then support is vital, and the quality of support is even more vital... the Electrajet site and software pictures look outdated, like nothing has been updated in a long while.

- Keep your scope, scantool, data/info systems separate and independent... if one of them breaks down the others can still be used... and they can be upgraded separately as required... if you're professional then this will save you downtime... if you're a hobbyist it will save you downtime also (you have a limited time each nite to "play" before going to bed so you can go to your daytime job the next day)... a tool should do its function and do it well (as opposed to doing many functions half-arsedly).

- the Pico 3423/3223 have a pretty deep buffer, deeper than I have seen on many scopes... you can use a long time base to see the general repetition of a signal and then zoom in on any portion (this is a very important feature to have for automotive use... big picture and small picture).

- if you can afford 4 channels, then get 4 channels... you won't regret it at all.

I am an EE by career and I have used the Fluke 199C and other portable and non-portable Tektronics and Agilent scopes... I like the Pico way better anytime, no doubt about it.

(This must be the most I have ever written...)

Cheers and Regards
Joe
:)

Sam,

If you don't mind me taking the lazy way here, let me just copy and paste somehting here that I have posted elswhere....

PicoScope isn't for everyone......

I do often get asked about what scope to choose. I don't
have an answer. You see, all scopes have their own set of
limitations. Some have more limitations than others :-p The
scope is only half the picture though. The tech is the
other half. You have to match the tech with the scope. The
most capable scope, not well matched to the user, is less
useful than a somewhat less capable unit that the tech
feels comfortable with. Almost any scope is better than
none.

That being said, sample rate performance is very important.
All the cool features don't mean much if the unit can't
perform. So, I tell techs to first narrow the field by
evaluating the DSO sample rate performance of the units
considered. Then choose based on features from that group.
I have a web based DSO Sample Rate Calculator available to
perform this comparison based on the specs and the math,
not the manufacturer's hype. It enables you to objectively
compare DSO raw performance.

When it comes to the analog variety of scope, sample rate
is meaningless. They are live. Problem is, you can't
freeze, store, print, share, manipulate, or many other
things you can do with the digital storage type. They make
good trainers, but students are not very likely to
encounter them in the field. Many of the skills are easily
transferable to the DSO though. Things like trigger, time
base, voltage scaling, etc.

That calculator allows you to compare the sample rate
performance of digital scopes. All you need is two specs.
The max ADC speed and the sample buffer size. This empowers
you to determine the raw performance of DSOs you may be
considering so you can narrow the field of choices and then
focus on features on the short list. The features don't
mean much if a scope can't perform when it comes to sample
rate. You can ignore the manufacturer's hype, and make an
objective comparison using the math. This can help avoid
getting something that can't perform.

The calculator is designed to calculate samples using one
channel. Different scopes handle the use of multiple
channels differently. Is the sample buffer shared? Is the
ADC shared? Etc. But it will be at it's best sample rate on
one channel. So, you can compare apples to apples.

Vertical resolution is another consideration. It is a
separate issue from actual sample rate (horizontal
resolution) and indicates how small a voltage change can be
detected. If you can imagine horizontal grid lines on the
screen, an 8bit scope will have 256 of them. Voltage
changes between the grid lines cannot be detected or
displayed. The voltage must rise or fall to the next grid
line to be detected. A 12bit scope has 4096 grid lines so
smaller voltage changes can be shown. This results in a
waveform with more vertical detail or resolution. A scope
with lower vertical resolution will have more of a stair
step effect on voltage changes when examined closely. A
scope with higher vertical resolution will have a smoother
more finely defined waveform.

jarvissamuel wrote on Jan 22^nd, 2009 at 6:52am:

Hello Sam1 and welcome if it has not been said before.  ... Sam

those videos were very good, thanks for sharing them. the last one shows how important to have a high res. graph.

Tom

may thanks for sharing. I noticed that the 3423 is a 12bit scope vs. the electraSpec/Jet which is 14bit.
having said that the pico is much better tool to have for the the more priority reasons stated earlier.
I also noticed the methods of connecting the units is different, with pico one needs to prob wires, with electraSpec/Jet, one need to purchase ECM brake_out connectors for each car ECM setup. one advantage here is that one doesn't have to wonder which wire on a CKP is the "correct" one probe. (end of second paragraph after fig.2 at http://www.picoauto.com/tutorials/vehicle-owner.html), however you pay for it. many connectors for multi ECMs.


Randy.
you fist post was a sharp ice-breaker. just that the ice was not ready for it. now, I take it you meant no offense.  :) I will surly consider CD#1 as you suggested. thanks

Sam,


Quote:

he electraSpec/Jet which is 14bit.

Your sheet shows 10 bit.  

There are a lot of different PCM connectors out there...that would get expensive.  In addition, many PCMs are a nightmare to access and direct probing can be done rather quickly in most cases.

In your linked example of a floating ground EDIS CKP...the correct orientation is when the waveform rises in the missing tooth area.

Just to clarify, I was just told that the ElectraSpec/Jet has an ADC for each channel.

Thanks for that, Sam.  It wasn't clear from the sheet.  So, the 2MHz max ADC speeed would not be divided by channels deployed.

Tom Roberts wrote on Jan 22^nd, 2009 at 4:44pm:

Sam, Quote: he electraSpec/Jet which is 14bit. Your sheet shows 10 bit.   There are a lot of different PCM connectors out there...that would get expensive.  In addition, many PCMs are a nightmare to access and direct probing can be done rather quickly in most cases. In your linked example of a floating ground EDIS CKP...the correct orientation is when the waveform rises in the missing tooth area.

Tom
what you said is correct. it is not 14 but only 10bit.

as to the correct orientation, could you please show a correct vs. incorrect screen shot of the waveform?

Thanks :)

jarvissamuel wrote on Jan 22^nd, 2009 at 6:52am:

...   Pico recently added advanced triggers as well to pico scope 6.  They did take away the merge feature (a favorite of mine) but I feel the other abilities make it worthwile. ...

what is the "merge feature" for? why did you like it? what are you doing to compensate for its absent?

what is the Advanced Triggers for?

thx

Sam,

You might find this a good read:

http://www.autonerdz.com/cgi/yabb2/YaBB.pl?num=1077376754

Reply 10 explains some of the issues with floating VR sensors

The incorrect orientation is inverted and the waveform will fall in the missing tooth area.  

I can dig one up for you later if you want.  We have our 'Group Therapy With The Picotologist' session tonight so I am off to set up for that.  

Sam1,

Tom might be a little busy right now since we are getting ready to start our monthly live conferencing, so I thought maybe I would address your questions.


Quote:

as to the correct orientation, could you please show a correct vs. incorrect screen shot of the waveform?

Below is a composite view of the current and incorrect orientation.


Quote:

what is the "merge feature" for?

The "merge feature" is for comparing one capture to another utilizing one screen. You can go one above another (max 4), overlay views, side-by-side (max 2), or 2x2 square (max 4). This is using the PicoScope 5 software.


Quote:

what is the Advanced Triggers for?

This can get real lengthy trying to type all of that out. Tom made a flash movie tutorial on this that goes into great detail on that. My advise would be to grab a bag of popcorn and watch the movie. I can give you a general overview later, but I'm running a little late right now preparing for the conference.

---

I noticed that list of items which come with the PicoQuad kit. and also the other items which do not come with it;

Pico’s 12 Channel
Secondary Signal Mixer
The FirstLook Pulse Sensor
Coil on Plug Probe
Universal Breakout Lead Set

what and how often a situation would arise which REALLY needs one of the above? I mean , had you not have it, it would have not been possible to fix the problem, or saved you lots of time using it.

thanks

Sam,

Just to clarify some things:

Merge Feature:
The merge feature that Samuel was talking about will be available on the next release of PicoScope 6 Automotive.  Instead of being called merge function this will now be called reference waveforms.  The attached picture shows the reference waveforms in action showing 3 of the exactly same crank waveforms displayed to give you an idea of the function.  I quickly took a saved waveform and took the crank waveform from it and added it to another waveform from the scope.  You can create known good ignition, crank, cam signals etc and save them as reference waveforms so you can quickly overlay them to determine if the pattern you are currently looking at falls within your good/bad parameters.  You can have a maximum of 8 reference waveforms shown on one view.  If you add more it will simply adds more views to view the additional reference waveforms.

Advanced Triggers:
Advanced triggers add greatly to the PicoScope functions available to the technician.  Most advanced triggers that the PicoScope comes with are only available to oscilloscopes that are in the next realm of pricing compared to the PicoScope.  Advanced triggers greatly improve the ability of the technician to capture the waveform that they are trying to get.  Matt Fanslow of Pico Technology wrote a quip about advanced triggers that I would recommend reading.  You can view that article at http://www.wavehook.com/dbase/article.html?article=aff9e1bd469fc5142d1f5be1c8642ddd.  

MixMaster Ignition Mixer:
Traditionally with the PicoScope you can view up to 4 different ignition signals at once (with the PS3423, 2 channels with the PS3223).  With the MixMaster you may view up to 12 channels paraded across the screen.  If you are interested in viewing paraded signals of all cylinders this piece of equipment makes it possible with the PicoScope.  

FirstLook Sensor:
The FirstLook Sensor is a piezoelectric sensor that allows you to view slight changes in pressure.  The way this sensor works is if there is no change in pressure the voltage does not change.  As soon as there is a slight change this sensor detects it and you can view it.  Common uses with it are to insert the FirstLook sensor into the exhaust pipe and view the pressure changes as each cylinder fires; also numerous people connect the unit to the vacuum port of the pressure regulator on the fuel injector rail and are able to see the pressure changes as each individual injector fires.  I personally consider this an essential tool for diagnosis but, I would invest in Pico's now WPS500x pressure transducer (when it becomes available for shipment) as this is to do everything thing that the FirstLook does plus measure cylinder pressures etc.

Coil on Plug Probe:
Typically, on coil on plug systems, you are limited to simply current ramping etc to determine the status on the coil.  Some people wish to be able to view the secondary pattern off the COP just like you can with traditional secondary ignition systems.  To be able to do this Pico came out with the COP probe that allows you to capture the secondary patterns from COP systems.  To capture the pattern you simply connect the COP probe to the PicoScope and touch the tip of the probe to the coil you wish to measure.  This will take some learning however as each model of coil is insulated differently and hence the kV represented will have to be taken with a grain of salt.  When comparing 8 individual coils on the same engine this is an excellent way to knock out a bad coil.

Universal Breakout Lead Set:
These leads come in small, medium and large with the medium and large fitting most pins on US vehicles.  Essentially what these leads allow you to do is connect to a sensor with out the need to damage the connector by back probing.  Most OEM's are putting in place ordinances where the technician can not back probe the sensor in fear of issues arising later in on in the vehicle life.  With the breakout leads you can safely connect to the sensor and obtain its values without the fear of damaging its connectors.  You can purchase the leads separately or all three sizes in a pack.

Needs that arise for the above additional tools at your disposal:
Mixmaster:  This would vary person to person and on your diagnostic technique. People that use big box analyzers will find the MixMaster essential.  Others will look first to their scan data and determine which cylinder is causing the issue and then inspect that cylinder first.  Scan data should work hand in hand with scope data for proper diagnosis of customer complaints.  If scan data doesn't point you in a direction, the MixMaster will come in handy in that instance.

FirstLook:  The FirstLook sensor will allow you to verify which cylinder is causing the issue, and also depending on how you use it, if it is fuel, mechanical, or electrical.  When used in the exhaust pipe and with an ignition trigger this can detect which cylinder is misfiring better than most scan tools.  Refer to thompsonautolabs.com for more information on this subject.

Coil on Plug Probe:  This comes down to personal diagnostic preference.  It depends on if you are used to diagnosing ignition problems through secondary waveforms or other methods such as current patterns.  If you are used to secondary waveforms and work on COP cars the COP probe is essential.  If you are used to current patterns Pico sells quality low noise current clamps also.

Universal Breakout Lead Set:
The breakout lead set allow you to connect to almost all sensors on the common car today.  You can purchase the breakout lead set or back probe the sensor and risk damaging the connector.

Regards,

Richard Boyd

---

Sam1

The file merge/composite feature originated in the pico scope 5 software and is currently available in it still as far as I know.  Basically it allowed taking two files and combining them and observing them in different views.  It could even be the same file combined to look at different areas in greater detail at the same time.  A great benefit of this was before and afters for customers.  The downside with the pico 5 software is the trigger(if present)  had to be identical to merge.

Pico six offered a merge feature starting at 6 0 0  but had fewer display styles but did not require the triggers be exactly the same.  I kept the version with the merge until the advanced triggers came out.

Tom  has a tutorial movie for merge among many others but I believe it is in the the Picogroup area.  I also have some posts there but if I get some time I will post some images of merge.

Sam

Sam1 wrote on Jan 22^nd, 2009 at 10:40pm:

I noticed that list of items which come with the PicoQuad kit. and also the other items which do not come with it; Pico’s 12 Channel Secondary Signal Mixer The FirstLook Pulse Sensor Coil on Plug Probe Universal Breakout Lead Set what and how often a situation would arise which REALLY needs one of the above? I mean , had you not have it, it would have not been possible to fix the problem, or saved you lots of time using it. thanks

Sam,

Those are "luxuary items" that save time or give your more data... but you can still get the job done without them.

Also note that the FLS pressure transducer measures the rate of change of pressure (see what Kennedy said)... so it can be a bit tricky to interpret the waveform.

Joe

What about a trigger lead? I remember reading about it being used. but don't see it in the list of items in the QuadKit nor in the extras.

Sam,

Not sure what you mean.  You can trigger off of any signal.  No special lead required.

Do you mean the TA032 inductive ignition trigger lead?  This is not in the kit, nor is it required to trigger ignition.  But it does produce a clean spike for triggering and some really like it.  We carry those but don't have them on our web store.

---

Richard Boyd (Kennedy),

Thank you for your contribution.   ;)  Feel free to visit again.


Just so there is no confusion among our visitors....


Quote:

Matt Fanslow of Pico Technology

Correction:

"Matt Fanslow of Crag Technologies" (just another Pico distributor), not Pico Technology.  As you are of Crag Technologies and also as the link to Wavehook that you posted is.

Some of us remember Matt as one of our Autonerdz Picogroup members:

http://www.autonerdz.com/picousers.htm

Matt is a great guy.  A man of integrity and I have a lot of respect for him.  I wish him the best.  

Also, Autonerdz is not Pico Technology.  We would be misrepresenting ourselves to claim that we were.  We are a Pico distributor specializing in automotive.  We just offer a unique package that no one else can match for those that want the complete PicoScope LSD 'Experience'  :o

Tom Roberts wrote on Jan 24^th, 2009 at 2:51pm:

Sam, Not sure what you mean. ...

post 166, middle of the third line [...trigger lead on cylinder #1 ...]
http://www.autonerdz.com/cgi/yabb2/YaBB.pl?num=1229231191/1

   I think the term is being misused. TRCO  would be referring to a 'synch' lead- a synchronizer- not a trigger.  
 It captures say, cylinder #1 on one trace, and the time per division gets set so that we just see or slightly better; two firing events of number one cylinder. All the events in between are those of the other cylinders. This is done for many sorts of captures and the cyl synch is used solely as a reference.
You want to end up with the time across the screen equal to 9 firing events (if you are working with an 8 cylinder motor. The cylinder you synch from will be at the beginning and end of the whole capture...
and cylinder firing events for all the others once each in between.
    When capturing ignition secondary events for instance, typically #1 cyl is used for a synch. This is not done because you cant get a capture of a secondary ignition event without a synch; just that if you dont have SOMETHING synched with them on the screen you wont know which spark plug firing  is which - like which is #2 cyl, which is 8, etc.
  You sound fairly new to scope use. On the PICO home site -Autonerdz is a business that sells the scope, PICO is the manufacturer- is a library of waveforms. You can find examples there as well as here.
 The synch lead seems to be no different than an inductive probe for a Digital Voltmeter such as is used for RPM measurement ( the one that clamps over the spark plug), in fact any inductive probe will work.
  I invite the others here to correct me if I am wrong.
 

Sam,

Fisher is correct.  The example you posted is one where an inductive sync probe was used other than the TA032.  The TA032 is constructed better then most, but the output is similar to others.

Of course, you can also use one of the included Pico capacitive secondary probes for sync as well.

fisher wrote on Jan 24^th, 2009 at 6:33pm:

I think the term is being misused. TRCO  would be referring to a 'synch' lead- a s...   You sound fairly new to scope use. ...

Thanks for explaining that.

Is there a synch lead in the QuadKit? (would the 60A or 600A clamp work?).
what would be a good place to start learning about scope use?

Sam1

Sam,

I think you are getting the different leads or probes confused with one another.

Allow me to put this into perspective:

For secondary ignition, you can use either a capacitive or inductive probe/lead for synchronization purposes. It doesn't matter which one you use. You are only using one or the other to know which cylinder is firing. If you didn't have a sync probe hooked up, you wouldn't know. Now, there are other ways to achieve the same thing, but let's avoid that right now to keep it simple.


Quote:

Is there a synch lead in the QuadKit?

Yes. This would be one of the four capacitive probes supplied in the kit. It is your option to purchase an inductive probe, but it really isn't necessary to parade a secondary ignition pattern without it. You can use the capacitive probe for that.


Quote:

(would the 60A or 600A clamp work?).

Not for secondary, but yes for current readings you might want to use for sync such as injection. I prefer to go the standard voltage test lead for that, still though, you could use it for sync in certain situations.


Quote:

what would be a good place to start learning about scope use?

You already found it. Ask lots of questions. We will help you out. That is what we do.  :)

thanks Carl.
now allow me to ask more questions (till I get my set of The Nerds CDs).

what is the different between capacitive or inductive probes? expand if you like to :) I am all ears.

The other way to know would be through the firing order, I remember when I used to use the old scope (Sun, Bear, Allen...). but then they used plug 1 "synch" lead, not sure how the "new tech" Picoscope hook up archives that.

I received the following from ElectraSpec/Jet:

Are you aware that the Parallel interface can transfer data faster than the USB1 interface!  The parallel interface has served us well and is now getting out of date due to the demand of play station type computers and the advent of USB2 interfaces which work properly with a smaller cross section of plug.

The time base dictates the sample rate as if you sampled at the max on that time base you would just see a block or waveform.  If you selected 500us time scale the scope would show a lot more detail with very little time between samples.

A screen capture with 500 ms as a time base records over 20 seconds of data and is only used for trend purposes.  When you want to see detail in waveforms we never go above 50 ms and if greater detail is required a lower time base is required.  Remember the screen of a PC is broken down into dots and the capture can only be displayed with dots on the screen.  In a resolution of 1024 X 768 which is the average resolution now, you only have 1,024 dots from side to side of the screen, take out the borders and you have less dots.  You are not able to put anymore dots in than what the screen dictates and that is one of the disadvantages of a digital scope.  If you require more, than you should be using a analogue scope and our product would not suit your needs.

Ultimately it comes down to what signal you want to read, when and what do you want to see.  Our scope is designed for Automotive use, with the technician which is using it has the captures setup with the right time/voltage scales as reference waveforms.

For Automotive work we have never had the need to unpack our CRO for use on cars, all the faults have been able to be detected within the scope of the Electrajet Equipment.

open for your comments.

Bryan-WI wrote on Jan 24^th, 2009 at 9:08pm:

On a vehicle with a distributor and seperate ignition coil  I hook up one capacitive lead to the coil wire then the other capacitive lead to the #1 spark plug wire. I trigger off the channel on cyl #1 and then I can look at the patterns in detail on the coil wire. You could look at secondary just using a capacitive lead on the coil wire but then you would have no way of knowing which cylinder is which.  I could do this with an inductive lead or "synch" lead, but that would have to go on cyl#1 for triggering purposes. I would have to have a capacitive lead on the coil wire to look at the secondary patterns in detail.  The inductive lead or "synch" lead will respond to the voltage in the spark plug wire and give you a signal to trigger off of but you will need a capacitive lead on the coil wire to look at the secondary signals in detail.   Some of my comments may be redundant, stupid, or self explanatory. Please humor me, I am trying to shed some light on the different leads to someone that hasn't used them before.  Bryan.

Why do we call one Inductive and the other capacitive? variation of shape? operation? ...?

Sam,


Quote:

When you want to see detail in waveforms we never go above 50 ms and if greater detail is required a lower time base is required.

With that scope and most others, that would be true because it isn't capable of maintaining enough sample rate to render detail at longer time bases.


Quote:

In a resolution of 1024 X 768 which is the average resolution now, you only have 1,024 dots from side to side of the screen

True but irrelevant.  When you are collecting over 2 million samples per channel per screen, of course you will not be able to see all that detail on a PC screen.... until you zoom in.  Then you will.   ;)

USB is much faster than Parallel but if you don't have much data to transfer Parallel can handle it.   Google it yourself.

BTW, USB 1.1 is not fast enough for PicoScope.  

inductive will only give you  a signal to trigger off of


capacitive will give you a signal with detail

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Bryan-WI wrote on Jan 24^th, 2009 at 10:56pm:

inductive will only give you  a signal to trigger off of capacitive will give you a signal with detail

and can I add?
Capacitive tip has a cylinder like top to "hug" the wire where as inductive tip has a coil on its clamping tip.

The inductive probe contains a coil/inductor and works by coupling to the rate of change in magnetic field (you see only a spike corresponding to secondary firing event when rate of change of magnetic field peaks).

The capacitive probe contains one "plate" of a capacitor (the other "plate" being the ignition secondary wire) and works by capacitively coupling to the signal in the secondary wire (you see the AC part of the whole secondary signal, from dwell->arc-fire->settle).

With the PicoScope, you can set the time base to a large value and capture "many" events like fisher said above (in regards to 8 cylinder ignition)... see the first attachment (1976 Datsun 4 cylinder ignition)...

red=capacative probe on coil.
blue=inductive probe on #1 (I could have used a capacitive probe on #1).


Then once you have captured a large trace, you can zoom in on places of interest... see the second attachment.

You get the big and small picture all in one go!

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So Sam, my Quickscope actually will do down to 200 nanoseconds per division (still only 256 samples on the screen).  One great place for literature is AESWave.com. They are here on the West Coast of the USA. They have two very good books for learning to use a scope. They have a LOT of accessories and they even sell PICO too but no forum there either.
 The two books are short and quite teach the basics... it is relavent to learn about thing like OHM's law, inductance, capacitance, floating grounds, electromagnetism... these things are gleaned from books about electricity... I have a couple good ones, one from the AESWave site as well as the two scope books from AESWave; and one Marine/ Industrial Engineer's manual for maintenance and repair of AC equipment.
 Education outside of scope use regarding electricity and electronics is an obvious necessity.

Do you see what we were talking about? The upper line is all the ignition events, sparks, and the blue trace was captured using an inductive probe.There are four firing events per two cycles; including that of the synch cylinder.
The synch cylinder, in the engine bay,  has a probe on it.
       I am talking about the captures just posted.

Oh yeah!
           Then see Joecar's second post, it shows the first firing event for the synch cylinder zoomed in. As I said the download for the operating software is free, if you see a psd file, or psdata file posted here, you can load it and zoom in on it. Bravo!

joecar+ wrote on Jan 25^th, 2009 at 1:48pm:

With the PicoScope, you can set the time base to a large value and capture "many" events like fisher said above (in regards to 8 cylinder ignition)... see the first attachment (1976 Datsun 4 cylinder ignition)... red=capacative probe on coil...

on coil high tension lead, not just on coil, right?

what about other cars with one coil per cylinder or per 2 cylinders, how would one get the firing parade display like the display of the old coil/dizy setup?

The capacitive probe was on the coil ht lead on that car...

On my other cars which have multiple coils, the capacitive probe works both ways: on the secondary lead and on the coil itself (clamp it on the coil core which wraps around the outside of the coil).

For my V6 waste-spark DIS which has 3 coils, I clamp on 3 capacitive probes.

For my V8 individual coil per plug, I use 2 capacitive probes at a time and view 2 at a time... or I use the COP probe and view one at a time... this is where a Mix Master would allow you to see all 8 paraded.

I have waveforms of those two on my other laptops (I have to find which one).

Cheers
Joe

fisher wrote on Jan 25^th, 2009 at 2:15pm:

So Sam, my Quickscope actually will do down to 200 nanoseconds per division (still only 256 samples on the screen).  One great place for literature is AESWave.com. They are here on the West Coast of the USA. They have two very good books for learning to use a scope. They have a LOT of accessories and they even sell PICO too but no forum there either.  The two books are short and quite teach the basics... it is relavent to learn about thing like OHM's law, inductance, capacitance, floating grounds, electromagnetism... these things are gleaned from books about electricity... I have a couple good ones, one from the AESWave site as well as the two scope books from AESWave; and one Marine/ Industrial Engineer's manual for maintenance and repair of AC equipment.  Education outside of scope use regarding electricity and electronics is an obvious necessity.

Fisher;
can you name a few of those books?
what do you think of Advanced Automotive Fault Diagnosis?

  I have not heard of your book. AESwave REALLY has the stuff. I was just there and got the names of these two: "ATTS:Getting to know Automotive Lab Scopes" and "Lab Scopes: Intro and Advanced".
  The first is about fifty dollars US and the second about forty U.S. dollars.
   If you go to their site you will see the column on the left, look for the books.

Sam1,

I couldn't find the particular traces I mentioned a few posts ago (I think it was on the laptop that required a new hard drive... I have about 4 laptops and several desktops... I lost count...  :D)...

but here is an example from my Firebird V8 ("Alloytec V8") showing #1 cylinder firing, #1 injector voltage, and the current thru INJ1 fuse which feeds the coils and injectors on bank 1 (odd cylinders)... I added the notation using MS Paint.

BTW:
see the injector voltage, it has an inductive kick upto almost 120V... I use the 20:1 attenuator for this (I read your other post), and I told channel C (the green one) that it was the 20:1 probe, this allows the  displayed voltage trace to be scaled correctly.

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Thanks Joe, it was nice of you to go hunt for this and post it. :)