"DIY Probe" projects - what kinds exist? - Page 1
Forum section: electronics / beginners

author: kalel
author_rank: Frequent Contributor
timestamp: August 24, 2017, 09:39:49 pm
content: So far, I've seen DIY logic analyzer probes with LEDs that show high/low states. I don't know if they do, but I assume some might "slow down" the frequency in order to display higher frequencies (I'm not sure if that is even useful or needed).I've seen DIY audio probes which seem to help with troubleshooting amplifier circuits, guitar effect pedals and such.I've also seen RF probes some of which are similar to the above with a diode added.I've also seen some non-contact probes from Mr. Carlson's Lab:Are there more types of DIY probes with some kind of instructions out there? I'm sure there are, and I'd like to hear about them.P.S. If this might be a better fit in another category, please feel free to move it, deleting my own posts is not allowed.

author: loxodes
author_rank: Contributor
timestamp: August 24, 2017, 10:27:29 pm
content: There are DIY designs for active differential probes (https://xellers.wordpress.com/electronics/1ghz-active-differential-probe/) and active single-ended probes (https://easyeda.com/andyfierman/project-g2QNnljhf).I've made simple passive RF near field probes (https://github.com/loxodes/emc_tools) that are suitable for.. qualitative measurements (https://github.com/loxodes/emc_tools/tree/master/doc)

author: cdev
author_rank: Super Contributor
timestamp: August 24, 2017, 11:13:10 pm
content: If you are not fixated on building a kit and need as good a "logic probe" as you can get as a beginner....you should pick up one of the super cheap FPGA based logic analyzers on ebay. (look for "24 MHz logic analyzer") I have seen them go for as little as $7. That is by far the best bang for your buck because you'll get 8 channels of logic capture you can grab and then scroll back through using software like sigrok. (which will also often decode it for you)The logic analyzer may even come with a cable and bunch of minigrabbers, or you should remember to pick up some compatible plugs and ribbon cable (or "dupont cables" with the male or female user friendly interconnects..) to make your own.Actually, the audio aspect of a logic probe can be useful in tracing wires.. very useful. But the proble I have that gets the most use in that area was meant for pulling cables like Ethernet cables through walls.. its a cable tracer.I also own a probe much like the one you picture and never use it, I use my logic analyzer. The probe and the logic analyzer both cost around the same but the logic analyzer is far more useful, the probe not as much -If I want to see if a pin is high or low I will often just use an LED. The audio would probably be useful if I thought to use it more.Check out the LAs.. Start athttp://sigrok.orgfor the free open source software and a list of compatible LAs.

author: Beamin
author_rank: Super Contributor
timestamp: August 25, 2017, 12:44:57 am
content: Does anyone know the cap values from the mrcarlsons lab project? I can't figure out if they are 10nf and 100nf or 10 pf and 100pf. He has numbers written and the larger caps are in uf. You kind of have to pause to see the schematic.

author: Cliff Matthews
author_rank: Unknown
timestamp: August 25, 2017, 01:47:16 am
content: +Beamin See YT channel "MrJohhhnnnyyy" his variation even Mr. Carlson likes. (He often answers viewer questions too).