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


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

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.

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.

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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.

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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.

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

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  The parallel interface has served us well and is now getting out of date due to the demand of play station type computers and the advent of USB2 interfaces which work properly with a smaller cross section of plug.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.

Sam,

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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.

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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. 

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


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.

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)...

=capacative probe on coil.
=inductive 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!