First Oscilloscope - Page 1
Forum section: electronics / beginners

author: rrittenhouse
author_rank: Newbie
timestamp: January 04, 2016, 04:45:03 pm
content: I am about to go pick up an HP 1222a for $30 but it's untested as he had no probes. He apparently has got some probes and said that I could test it even when I show up. Ad is here:http://columbus.craigslist.org/ele/5350024006.htmlI saw that it had a single dot on the screen but I assume that's because he had no probes hooked up. It's been YEARS since i've touched an o-scope.I assume that for $30 even if its dead it's probably a fun project to tinker with. Let's just hope I don't need an o-scope to fix the....o-scopeI found the manual for it but was quickly overwhelmed with "Why not just save up for a Rigol?". I figure I should learn/break an older one before making some mistakes on a newer scope.Thoughts on this model? Good deal to pick it up even if its junk?Thanks

author: Isad
author_rank: Frequent Contributor
timestamp: January 04, 2016, 04:53:51 pm
content: For 30$ even just to take it apart its worth itmight be broken sicne i dont think that that scopehas a dot mode but idk i havent touched any kinde ofold HP scope.Btw why dont you get the hp digitizing oscilloscopeseems to be working but idk.Good luck with it .

author: jitter
author_rank: Frequent Contributor
timestamp: January 04, 2016, 04:55:10 pm
content: An analogue scope will show a dot when set to xy-mode without any signals connected.Perhaps it was when they took the photo?When googling for a better photo I stumbled acrossthisthread on this forum.

author: Isad
author_rank: Frequent Contributor
timestamp: January 04, 2016, 04:56:53 pm
content: Quote from: jitter on January 04, 2016, 04:55:10 pmI dont think that scope has xy-mode since there is no button indicating thatbut idk for sure.

author: Audioguru
author_rank: Super Contributor
timestamp: January 04, 2016, 04:57:09 pm
content: A dot on the screen means that its horizontal oscillator or horizontal amplifier does not work. The dot might have burned a mark on the screen.

author: jitter
author_rank: Frequent Contributor
timestamp: January 04, 2016, 05:17:39 pm
content: Quote from: Isad on January 04, 2016, 04:56:53 pmIt has X-Y mode. Look at the photo of the link in my previous post. It has no separate knob for it, but next to the time/div knob there's the text: "MAGNIFIER SET TO CAL FOR X - Y".That is the little knob on the time/div, but it's missing on the scope in question.

author: rrittenhouse
author_rank: Newbie
timestamp: January 04, 2016, 06:00:22 pm
content: Thanks for the reply. I only grabbed this one because it was local. Like 5 minutes from house to house. He didn't have proper probes so I really didn't get to test it besides turning it on and playing with knobs.The HP digitizing scope is about 45 minutes away so I dismissed it. That, and I don't claim to know much about scopes and if that one is good or not. I'll check on it though and do more research on that one. Thanks!

author: Isad
author_rank: Frequent Contributor
timestamp: January 04, 2016, 06:14:16 pm
content: Quote from: rrittenhouse on January 04, 2016, 06:00:22 pmThe digitizing scope seems to be working tho he doesntshow a waveform but only the line a scope display so if yougo to that persons house make sure you play around with it.Quote from: jitter on January 04, 2016, 05:17:39 pmOh i didnt see that post.Sorry Your right.

author: rrittenhouse
author_rank: Newbie
timestamp: January 04, 2016, 08:25:00 pm
content: Thanks for the replies everyone. I will have to buy some probes and give this one a test. For 30, i'll at least have something to tinker with while I get another scope that works. I went and picked it up on my lunch break. I made sure to introduce him about EEVBlog while I was there. He just had this sitting around from when he went to school for Electronics in '89.I'm assuming that probes are pretty standard? I need to do some more research on that and then purchase a couple. Ideally, if it is broke, I would love to be able to use the probes on another scope. I'm sure that it's probably able to be done; I just figured I would ask.Thanks!

author: tggzzz
author_rank: Super Contributor
timestamp: January 04, 2016, 09:27:44 pm
content: Quote from: rrittenhouse on January 04, 2016, 08:25:00 pmIf you do just the tiniest bit of research (I.e. look at a distributor such as Newark or digikey) you will find that bog standard probes cast from $10 to $10000. And then there are the expensive probes...

author: rrittenhouse
author_rank: Newbie
timestamp: January 04, 2016, 11:05:14 pm
content: I'm probably going to grab these unless someone says its a bad idea?Hantek 2 X 100MHz Oscilloscope Clip Probes with Accessory Kithttps://www.amazon.com/dp/B0030KWM30/ref=cm_sw_r_other_awd_-OVIwbKMETHPZ

author: rdl
author_rank: Super Contributor
timestamp: January 05, 2016, 01:02:33 am
content: Those should be fine. You can find P6100 probes and others on ebay for a little cheaper, they'll do the job too. Look for free shipping from US only for good deals with fast delivery.

author: rrittenhouse
author_rank: Newbie
timestamp: January 05, 2016, 04:18:09 pm
content: Quote from: rdl on January 05, 2016, 01:02:33 amThanks. I went ahead and ordered the ones from Amazon so they get here quicker haha. I'm impatient and i'm sure i'll be disappointed (but motivated) to fix the HP 1222a scope. I was trying to look up how to build a scope but I didn't know if I should trust doing something like that. It looked like for an x10 scope that you could just get a bnc connector, 50 ohm coax, 2 (specific value) resistors, and a specific value cap, a probe, an alligator clip, etc. But I just figured even if I don't get this one working I'll end up buying something else that is known to work.Thanks