Low cost Oscilloscope

[Hawke]

I have a couple of old style technology race cars. Points, coil and mechanical distributor stuff.

From time to time, we find problems at the track, and with no diagnosis tools, we keep changing out things - leads, coils, condensers, plugs etc, till the thing works again.

I've seen some low cost oscilloscopes that could help in pointing out what is the real problem.

The DSO Nano with a capacitive secondary pick up seems to fit the bill.

http://www.seeedstudio.com/depot/DSO-Nano-v3-p-1358.html?cPath=63_65

Has anyone had any experience with such a thing.

Before someone suggests to change to electronic ignition, it is not possible.

 

[Jacobson]

Is an oscilloscope basically a multimeter used for reading voltage, but it displays the data on a graph, instead of just the exact value in the present?

 

[wild cowboy]

Is an oscilloscope basically a multimeter used for reading voltage, but it displays the data on a graph, instead of just the exact value in the present?

at DC that is basically what it is, just graphing voltage against time - but a scope can also have a triggering feature for use in high frequency applications, such as on modern cars to watch an injector fire or a myriad of other things

 

[pi_guy]

I have a couple of old style technology race cars. Points, coil and mechanical distributor stuff.

From time to time, we find problems at the track, and with no diagnosis tools, we keep changing out things - leads, coils, condensers, plugs etc, till the thing works again.

I've seen some low cost oscilloscopes that could help in pointing out what is the real problem.

The DSO Nano with a capacitive secondary pick up seems to fit the bill.

http://www.seeedstudio.com/depot/DSO-Nano-v3-p-1358.html?cPath=63_65

Has anyone had any experience with such a thing.

Before someone suggests to change to electronic ignition, it is not possible.

I do not know if that would be your best solution.
I use one it was about $600 a two channel, but the cost in probes exceeded the cost of the scope. But I mostly use it on electronic ignitions or to see packets of data passed to a logger box.
A non contact hi voltage probe will show the spark plug trace, which is a quick way of figuring out if you have a dead cylinder.
You can then use it to watch the signal generated by the points and measure the output of the coil. With the proper probes you can measure coil voltage on channel one and then check each plug for that trace on channel two to see how off it was from coil trace
Often I use it to monitor the signal generated by the crank or cam trigger, if there is excessive noise in those signals often the motor will not start or run horribly.

 

[Vegaman_Dan]

An oscilloscope also show you AC voltage spikes, misfires, and other noise on the circuit. It can tell you if you have a failing condenser in the distributor, for example.

 

[Shadowdog500]

Heck, I gave my old Tectronics 545A scope away because I havent used it in years.
Never needed it to work on point engines. Never needed more than a DMM to check a point ignition system. And an advance timing light to check the curve in the distributor at the track. We had a distributor stand at work that was neat for setting advance curves.

This may help you pinpoint the problem when you have them.
http://www.jalopyjournal.com/forum/threads/how-to-ignition-system-troubleshooting-101.182665/

I used to play with drag cars when dual point distributors were king. When Mallory pointless distributors first came out, everyone I know jumped on that including myself. Then MSD became king when it came out.
Is there a reason you haven't switched yet? I still have points in my willys jeep, but would go electronic in a race car if I could. More dependable and hotter spark.

Chris

 

[JohnnieMo]

I've used one of these before

Www.bitscope.com

Use your laptop for the display and connect in a little box to do the measuring.

Sent from my Passport

 

[A_Pmech]

Is an oscilloscope basically a multimeter used for reading voltage, but it displays the data on a graph, instead of just the exact value in the present?

Yes, an oscilloscope is a graphical time domain voltmeter.

 

[MechanicNamedJohn]

I just ordered the Hantek VII kit, be here in 2 days. Also just ordered a few items to build two pressure transducers.

 

[Hawke]

"Is there a reason you haven't switched yet? I still have points in my willy jeep, but would go electronic in a race car if I could. More dependable and hotter spark. "

Unfortunately, in this part of the world, Formula Ford's, have to use original equipment ignition.

 

[madcrisis]

If your just using it for quick diagnostics, and that one has good reviews it'll probably work. Realize it has limitations but should work.

 

[gungatim]

as others said, there are scope aps for laptops but I have no experience with them. I did just pick up two used older scopes, an HP and an Leader. again, they both work and were <$10 ea, but without probes, the price goes up exponetially...they are really handy though and can do a lot more with cars even with electronic ignition and computer control than simply reading codes. For example, you can "see" every signal for injectors, sensors, ignition, etc.

 

[GTA Matt]

The u-scope from aes wave is the same unit with much better (custom) firmware. They also have it with a lead and amp probe kit all together.

 

[theoldwizard1]

I've seen some low cost oscilloscopes that could help in pointing out what is the real problem.

The DSO Nano with a capacitive secondary pick up seems to fit the bill.

http://www.seeedstudio.com/depot/DSO-Nano-v3-p-1358.html?cPath=63_65

You get what you pay for and at less than $100 you are not getting much. Tha analog front end is spec'd for 200kHz, meaning you might miss those bery short spikes completely.

It is nice to have a "complete" standalone 'scope, but I suspect you will get much better bang for your buck with a pocket 'scope front ending a PC/tablet.

Picoscope is the king in this area right now and they have a special version designed for automotive use. Very $$$ !

I do not know if that would be your best solution.
I use one it was about $600 a two channel, but the cost in probes exceeded the cost of the scope.

Yep ! Hit the nail on the head !!!

 

[kiatech]

I've heard good about the pico scope.

 

[kf4zht]

****, I have owned several 10 and 50 meg scopes and never paid more than $40 for one. They are plentiful due to the number of schools and industry needs that buy them then surplus them 10 years later. If you are working on cars you don't need anything new.

Find the electronics surplus place in your area or hit up an amateur radio show.

 

[Stuart in MN]

One of my friends bought a oscilloscope plug in for his laptop computer - I don't know the brand, it could have been the bitscope mentioned above but there are a number of them on the market. He used it for troubleshooting a Megasquirt fuel injection system he'd built, and it worked quite well. I think they provide a lot of bang for the buck; they may not have the performance of a high end real 'scope but they still do quite a bit.

 

[67King]

Has anyone had any experience with such a thing.

I've used this one to make sure my reference sensors were working: http://www.dpcav.com/xcart/Digital-Oscilloscope-Discontinued.html?featured=

Worked very well. A little clunky, its replacement is half the cost of the one you showed, but for working in the garage, it was a good tool to have. That said, I would very much highly recommend going for one. The situation that made me buy it was a car that had multiple failures, and I was changing out one thing at a time and couldn't get it to run (I eventually started takign stuff off of it and putting on a running car to try to make it not run, which is how I found out both computers (wacky Germans) were bad, as well as the alarm system). Don't have that kind of luxury at the track.

 

[AndyA]

I have a Tektronix 475. It's a 100MHz scope. I think I paid $125 for it in the mid 1990s.

 

[SuburbanRuss]

Have you tried military surplus, or aircraft surplus??? I got mine through Boeing Surplus for $25...

 

[pi_guy]

I went with this one, the 100mhz version.
http://www.saelig.com/PSHA/M00062009.htm
I tried to find a link for some of the probes that I use, which is really the key to getting good use out of a scope. but had no luck

 

[ttpete]

"Is there a reason you haven't switched yet? I still have points in my willy jeep, but would go electronic in a race car if I could. More dependable and hotter spark. "

Unfortunately, in this part of the world, Formula Ford's, have to use original equipment ignition.

If you're looking for a set of points with very low mass for high rpm applications, the ones used in mark 20 Mercury outboards from the 1950s are the best. I've used them for years in motorcycles.

 

[pi_guy]

If you're looking for a set of points with very low mass for high rpm applications, the ones used in mark 20 Mercury outboards from the 1950s are the best. I've used them for years in motorcycles.

The 1600 FF is a push rod motor, with a push it red line about 7200. Much more than that you have pulled the pin<hand grenade>. Bosch I believe makes the better competition points.
There is some discussion on Apex regarding the issue with points and ignition scatter. Most important is having the distributor tested and profiled to work properly at needed rpm range.

 

[ttpete]

The 1600 FF is a push rod motor, with a push it red line about 7200. Much more than that you have pulled the pin<hand grenade>. Bosch I believe makes the better competition points.
There is some discussion on Apex regarding the issue with points and ignition scatter. Most important is having the distributor tested and profiled to work properly at needed rpm range.

The Bendix points have no hinge. The breaker arm is a thin flexible piece of spring steel with a contact on the end. There is another piece of spring steel with a rubbing block/pusher that rides on the cam and pushes the breaker arm open. Both are mounted on the base with a screw and insulating washers. I've used them at 8000 rpm with no problems.

 

[SuzukiGS750EZ]

They're good for amp setup too. I'd be interested in a cheaper one as well

 

[y20dth]

we keep changing out things - leads, coils, condensers, plugs etc, till the thing works again.

If that is your way of diagnosing a point-based ignition system, no oscilloscope is going to help you.
Take a class.

 

[theoldwizard1]

If you live in an area where there are military or other "high tech" surplus at auction, there are some great prices on used Tektronix or HP scopes. I am not certain what it would cost to have it recalibrated, but it is probably worth it.

Probes can kill you $$$$

The big win on modern scopes is memory. This is an incredibly powerful feature that very few portable/lugable 'scopes from the 1990s had.

The "standard" in new, low cost digital 'scopes is Rigol. $400 for a 4 channel 50MHz digital storage 'scope is a steal