Blast from the past Hp130c!! Working! - Page 1
Forum section: electronics / testgear

author: kingoftaurus
author_rank: Contributor
timestamp: March 27, 2014, 03:11:35 am
content: Hello all!I'm new to the forum and I just recently became the proud new owner of an HP130c!http://www.hpmemory.org/timeline/bob_devries/hp130c_01.htmI was searching for my first Oscilloscope to have for my "lab" and I came across this from someones old storage bin on craigslist!I acquired it for 50$ bucks.At first I was very skeptical that it would turn on. I plugged it into the wall, and nothing... So I was sad.I did some simple tests to see maybe why it wasn't turning on, and the first thing I went for was input power at the plug on the rear.Low and behold, nothing. SO I tested the cable, and it worked just fine, but had a significant amount of tarnish on the plug. Rubbed all that off and plugged it back in.Flipped the switch and...ON!!!!... But nothing on display.. ugh lol.SO I downloaded the manual to see if maybe it was me. After reading for a few hours, I pressed the "beam finder" button and... A green spot appeared! So the display WORKS!!Read the manual some more and did a functional test. I managed to actually get a square wave to pop up on the screen. Albeit quite.. quite.. fuzzy. Sharp lines, but noisy as all get out. I hooked up an A/C to A/C 16v wall wart and hooked up the leads and I got a very.. VERY clean looking sine wave to appear.After reading some more on how to use an Oscilloscope.. (keep in mind this is my first time EVER using an Oscilloscope) I did the calculations for what I saw on the screen (following the instructions to the letter) (seriously, these instructions were made for me lol) And what appeared was 15.5v and 55hz. SO.. its about 10% out of calibration.Fifty one years.. and only 10% out of calibration?!! Jesus, I'd love to see any modern day Oscilloscope last that long, and have been through military usage for years, and still be that close to calibration.. or working at all.So over the next few weeks, I'm going to fix this thing up to 100% and have this as my first, and my most loved oscilloscope in my career path!I am an electronics hobbyist currently, but I am aspiring to become an Electrical Engineer and or get a degree in Mechatronics or more.All I do is spend time all day tinkering with electronics and ever since I was a kid I ALWAYS tore things apart to see how they worked.Unfortunately, life happened. I'm 30 years old now... But i'm determined to catch up!I live in Las Vegas, Nevada.Thanks all for viewing my post and I hope to be a valued member of the community!

author: echen1024
author_rank: Super Contributor
timestamp: March 27, 2014, 03:23:10 am
content: 10% out of cal might not be the scope. Mains frequency varies, as well as your wall wart output.

author: kingoftaurus
author_rank: Contributor
timestamp: March 27, 2014, 03:55:48 am
content: I did hook it up to a multimeter, and it said 60hz and 16v. Interesting that a multimeter can even test Hz to begin with.But then again, its a crummy DMM and perhaps even its wrong.. but after 51 years, im pretty sure its the scope lol. (could it seriously still be in spec after that long?)

author: Mr. Coffee
author_rank: Regular Contributor
timestamp: March 27, 2014, 04:06:41 am
content: Be careful when plugging in old electronic equipment untilat leastthe electrolytic capacitors have been replaced and a general safety and condition inspection has been performed. Having put that 2 cents in, welcome to the forum and that is a way cool find!

author: kingoftaurus
author_rank: Contributor
timestamp: March 27, 2014, 04:13:56 am
content: Quote from: Mr. Coffee on March 27, 2014, 04:06:41 amWell, I did notice that one of the caps looks like it let out the magic smoke a while ago, there's even a stain on the lid I took off. I still plugged it in (big balls) and turned it on with thick electricians gloves.Too late on that part though. I'm not so sure if "modern" caps will be a good replacement for those? I see a total of 8 caps in there lol. So simple back then. They all look to be about.1z50v"z"? uhhh

author: Vgkid
author_rank: Super Contributor
timestamp: March 27, 2014, 04:22:40 am
content: Modern electro's are a good replacement, albeit a smaller package.Mains frequency is rather stable when comparing the frequency to a reading on a O-scope.http://leapsecond.com/pages/mains/

author: echen1024
author_rank: Super Contributor
timestamp: March 27, 2014, 04:23:41 am
content: Quote from: kingoftaurus on March 27, 2014, 03:55:48 amYes, if your DMM says so, then it probably is the scope. Try performing a simple cal on it if you have a function generator.

author: kingoftaurus
author_rank: Contributor
timestamp: March 27, 2014, 04:56:56 am
content: unfortunately I do not have one.I'm trying to build one.. but that's the next step. The first was to have an Oscilloscope

author: Vgkid
author_rank: Super Contributor
timestamp: March 27, 2014, 05:47:46 am
content: What make/ model is your multimeter?

author: Bored@Work
author_rank: Super Contributor
timestamp: March 27, 2014, 06:17:41 am
content: Did you let the oscilloscope warm up for some time? That thing contains tubes (and I don't mean just the CRT).

author: kingoftaurus
author_rank: Contributor
timestamp: March 27, 2014, 06:35:15 am
content: Quote from: Vgkid on March 27, 2014, 05:47:46 amIts an Extech MN36Quote from: Bored@Work on March 27, 2014, 06:17:41 amYeah it was on for about a half hour before I started poking around

author: Vgkid
author_rank: Super Contributor
timestamp: March 27, 2014, 07:16:17 am
content: Lets see, your meter has a 1% accuracy on the frequency range, so at 60Hz thats (+/-) 6 Hz.on voltage at 60Hz it is .8% +5D on the 4.00v range, and 1.2% on the other ranges(mains freq only for those errors). for frequencies up to 400 Hz, the error is 2%+5DSo for the voltage to be 10% off, then it would be the scope, they only had an accuracy of 3%(VP-P/Freq) when new anyways.

author: oldway
author_rank: Super Contributor
timestamp: March 27, 2014, 07:45:36 am
content: I read your comments with fun because it reminded me of my beginnings in electronics, when I was 15 years old and I bought and assembled, my first oscilloscope, an Heathkit IO-12E.I felt the same wonder you feel today.On a forum where some consider it essential to have a digital oscilloscope of several hundreds MHz and a 6-digits multimeter to test a simple 555 oscillator circuit, your thread is interesting.But you quickly find the limitations of your new oscilloscope.If you like HP products, I suggest you try to buy a HP1740A in good shape.They are cheap and they are really great analog oscilloscopes, nothing comparable with the HP130C you just bought.

author: VK5RC
author_rank: Unknown
timestamp: March 27, 2014, 08:56:49 am
content: Great start, do be careful with thermionic valve gear, make a 'chicken stick' high voltage discharger.

author: Mr. Coffee
author_rank: Regular Contributor
timestamp: March 27, 2014, 12:58:43 pm
content: Modern caps are better than ever. I get my high voltage capacitors from Just Radios (online, and based in Canada). Because they have can capacitors, etc. in the voltage ratings I need for tube equipment.For function generators, I just completed this kithttp://www.ebay.com/itm/AE20125-10-MHz-Sweep-DDS-Function-Generator-Kit-with-USB-and-Modulation-/251169054479and am extremely happy with it so far. If you go for it, make sure you pay the little extra and get the case for it. I had to make mine, and though it turned out nicely, I wish I had just bought the optional case.

author: megajocke
author_rank: Regular Contributor
timestamp: March 27, 2014, 07:19:14 pm
content: Nice scope!Quote from: kingoftaurus on March 27, 2014, 06:35:15 amDid you also make sure the vernier knobs are set to "CAL"?

author: kingoftaurus
author_rank: Contributor
timestamp: March 29, 2014, 01:53:34 am
content: Quote from: megajocke on March 27, 2014, 07:19:14 pmYes sir I read the entire manualI'm very blessed to have a manual lol

author: Mr. Coffee
author_rank: Regular Contributor
timestamp: March 31, 2014, 01:24:13 am
content: Quote from: kingoftaurus on March 29, 2014, 01:53:34 amThat's no lie. Some old manuals are easy to find online and some are almost impossible.