Hi Guys,
I fixed an old scope that belongs to my radio club last night but it has no probes.
I was hoping for lower frequency stuff such as checking ripple in power supplies, etc.
it might be acceptable to homebrew one using an alligator clip for negative,
and a spare DMM probe that I have in the junk box for positive.

I'm wondering if anyone can tell me what's in the trimmer circuit besides the
capacitor used to trim the probe lead?
Cheers, Art.

 

Sure you can "make do" with a piece of coax, an aligator clip and a pointy thing...

Or you could just buy a set of new 'scope probes from ebay for $12 with multiple attachments, trimmer and 10:1 switch all built in.

Your choice.

 

The trimmer cap is used for a 10:1 probe. It's not needed for a 1:1 (direct) probe.

 

Ah, ok.. the commercial 1x probes are usually also 10x probes here (with a switch), so they all have the trimmer.

Yeah, RB, err... I fixed the thing, someone else can buy the leads

Last club meeting someone brings a linear power supply they made from scratch to
use the scope to test it's capacitors are big enough to smooth the DC supply.
Scope has no power cable.

Last night I bring the IEC power cable so if anyone wants to use it it's there.
Scope has no test leads.. it's a freaken display piece
I power it up and it starts to stink the room so I turn it off, take it home,
change electrolytics around the PSU, and it goes fine and no smoke,
so I'm guessing the transformer was about to burn.

 

Using BNC male connector and cable for scope, and another side using two aligator clips.

 

Using BNC male connector and cable for scope, and another side using two aligator clips.

Nice Idea, I did consider alligator clips for CH2, and probe + alligator clip for CH1.
Just depends how many half alligator clip leads I have..
Alligator clips are a bit like gold at my place

Someone had better be using this thing!

 

Hello,

Perhaps the following link might interest you:
http://cromwell-intl.com/radio/probes.html

Bertus

 

Nice Idea, I did consider alligator clips for CH2, and probe + alligator clip for CH1.
Just depends how many half alligator clip leads I have..
Alligator clips are a bit like gold at my place

Someone had better be using this thing!

You also can be using small SMD IC Single Hook Clip.