Wikipedia:Reference desk/Archives/Science/2012 June 23

Science desk
< June 22 << May | June | Jul >> June 24 >
Welcome to the Wikipedia Science Reference Desk Archives
The page you are currently viewing is an archive page. While you can leave answers for any questions shown below, please ask new questions on one of the current reference desk pages.


June 23 edit

Dissolving sulfur edit

I have a nylon cloth that has minerals impregnated in it. I think that one of them is elemental sulfur. The rest of them should be sulfides and oxides of iron, zinc, calcium and lead, and lead sulphate may be there as well. The cloth has a red/orange colour to it that is removed if I soak it in dilute HCl, HNO3 or H2SO4, but not removed if I soak it in EDTA or water. The EDTA liquor contains a fair bit of iron, so I think the red colour is not due to iron. The article on sulfur says that it dissolves in carbon disulfide, benzene and toluene, but my ICP-OES isn't set up to run organics. Is there anything aqueous that can selectively dissolve only the elemental sulfur, if it is in fact the cause of the red colour? 203.27.72.5 (talk) 07:26, 23 June 2012 (UTC)[reply]

Is there no emulsifier to do the job? Plasmic Physics (talk) 08:49, 23 June 2012 (UTC)[reply]
Can you elaborate a bit on that? I don't really want an emulsion, because I want to analyse it on the ICP, but I suppose if I formed an emulsion I could separate the sulfur suspended in the liquor from the rest of the cloth and then oxidize to sulphate to solubulize and go from there. What emulsifier could I use for that? 101.172.85.63 (talk) 09:43, 23 June 2012 (UTC)[reply]
I did a bit of googling and found that ethoxy nonylphenol is a good candidate for the emulsification of sulfur. Plasmic Physics (talk) 10:36, 23 June 2012 (UTC)[reply]
I'm not familiar with the opperation of that particular piece of laboratory equipment, but why not just just dissolve the sulfur in benzene or tolluene, and then recover it by vacuum distillation? Plasmic Physics (talk) 10:41, 23 June 2012 (UTC)[reply]
My lab isn't really set up for organics at all...I don't have a vacuum distillation rig or anything like that. I could just wait until the stuff evaporates in the fumecupboard though. The lab normally only does metal assays on mining samples, but they've thrown me a bit of a curve ball. I don't think I'm going to have any of the emulsifiers on hand, so I think I'm just going to soak the fabric in CS2 and see if it gets rid of the red colour. Do you think elemental sulfur could account for the red colour in a nylon fabric? I'm thinking red/orange is pretty close to yellow sulfur, but it could potentially also be another allotrope, couldn't it? 101.172.85.63 (talk) 11:00, 23 June 2012 (UTC)[reply]
I'm really not sure, I'm not familiar enough with sulfur allotropes to give an answer to that. Plasmic Physics (talk) 11:55, 23 June 2012 (UTC)[reply]
It could be an arsenic sulfide. Plasmic Physics (talk) 12:23, 23 June 2012 (UTC)[reply]
That's not unreasonable, considering arsenic is often associated with heavy metals. Plasmic Physics (talk) 12:52, 23 June 2012 (UTC)[reply]
Now that I think about it, what would free sulfur be doing in the sample anyway? It's usually associated with reducing soils, which does not seem to be the case here. Plasmic Physics (talk) 12:59, 23 June 2012 (UTC)[reply]
It's possibly produced as a colloid in the treatment of sulfide ores. 203.27.72.5 (talk) 23:25, 23 June 2012 (UTC)[reply]
~15 hours of soaking in 100% CS2 did not remove the red colour. Now I'm thinking the EDTA only moved iron oxides and hydroxides, but left the pyrite behind. I'm getting desperate, so I just dumped samples of the cloth into hydrogen peroxide, calcium hypochlorite and household bleach. Hope fully something cleans it. The HCl I originally used actually cleaned it up pretty nicely, but chloride ion is a bit too corrosive to use in this application. 203.27.72.5 (talk) 00:49, 24 June 2012 (UTC)[reply]
Have yout tried an alkaline solution yet? Plasmic Physics (talk) 05:47, 24 June 2012 (UTC)[reply]
Try a free radical reaction with a Fenton type solution: a combination of iron(2+) sulfate and hydrogen peroxide. That should pack a punch. Plasmic Physics (talk) 06:20, 24 June 2012 (UTC)[reply]
A strong alkaline solution will dissolve the nylon too, so best to steer clear of that. Stong acids will also damage nylon, and so will heat. Is it better to throw out the cloth and buy whatever it is new? As all thos chemicals and your time will cost. Graeme Bartlett (talk) 10:42, 24 June 2012 (UTC)[reply]
Larox filter cloths are $20,000 each, and they're clogging up 5x faster than expected. 101.173.170.147 (talk) 11:45, 24 June 2012 (UTC)[reply]
If it is an arsenic sulfide, it should be soluble in a solution of oxalic ammine with excess ammonia. Plasmic Physics (talk) 11:57, 24 June 2012 (UTC)[reply]
The manufacturer recommended trying oxalic acid but I don't have any. I thought that the EDTA would be a good alternative, and it did nothing, so I think the oxalic acid will be much the same. I've now tried; HCl, H2SO4, HNO3, water, EDTA, diesel, bleach, Ca(OCl)2, H2O2, acetone, THF, ethanol, methanol and carbon disulfide. HCl gave the best results, but the engineers are worried about corrosion on the filter press itself if we use that. Other than that, only H2SO4 and HNO3 did anything, and they didn't do much. Fenton's reagent sounds like it will attack the nylon, but thanks for pointing it out anyway; I realised it was just what I was looking for for something else! I doubt it's arsenic. I checked the assay numbers and arsenic is at ppm levels. 101.173.170.147 (talk) 12:02, 24 June 2012 (UTC)[reply]
Oxalic acid is quite different from ammonium oxalate, and works differently from EDTA. Oxalic acid can be obtained from a local hardware store, it's used to treat wood before it's painted. Just neutralise some oxalic acid with excess ammonia over some heat, that should give you ammonium oxalate. In any case, have you tried running diagnostics on a sample of the residue? Take a scraping, or pick off some pieces of the contaminant and react it with concentrated hydrochloric acid, analyse the resulting solution with the IPC-OES against a hydrochloric reference. At least that way you know what you are dealing with. That way, we can be more helpful, rather than just guessing. Plasmic Physics (talk) 12:25, 24 June 2012 (UTC)[reply]
The very first thing I did was cut of 4 samples of ~0.1g and digest them in conc. HNO2, HCl and HF and analyse on the ICP. The results showed that it contained significant Fe, Zn, Pb, Ca and S. There was a little bit of Si, but not much. Everything else that is detectable was trace. Other than S and Si, I can't see non-metals on the ICP. 101.173.170.147 (talk) 12:52, 24 June 2012 (UTC)[reply]
No, no, I meant after you've removed the other contaminants. Treat a sample with EDTA to was out all the contaminants to leave just the unknown residue on te cloth. Then wash it thoroughly with deionised water, and treat it with the conc. HCl. Plasmic Physics (talk) 12:59, 24 June 2012 (UTC)[reply]

Entomologist named "Nonfried" (fl. 1893-1900) edit

Hi all. Nonfried (fl. 1893-1900, initials A. F.) is apparently the species authority for a number of beetles. See: Eligmodermini, Lampetis, Metopocoilus giganteus, and so on. So, who was this chap? --Shirt58 (talk) 11:02, 23 June 2012 (UTC)[reply]

This document gives a bit of information: "Anton Franz (Antonín František) Nonfried (1854–1923). Based in Rakovník (= Rakonitz), Czech Republic, Nonfried ran a business with insects. His private collection was mostly sold (e.g., the cetonids are deposited in Museum für Naturkunde Berlin, Germany; HORN et al. 1990) but a small part, including several types, was acquired by NMP" [National Museum, Prague]. Obviously a sober, responsible person. Clarityfiend (talk) 15:28, 23 June 2012 (UTC)[reply]
Thank you! And NONFRIED Anton Franz, *16.10.1854, +16.12.1923... Oh dear, not much to start an article on... --Shirt58 (talk) 16:36, 23 June 2012 (UTC)[reply]
I'm guessing that Nonfried had a basket full of half-baked theories ? :-) StuRat (talk) 17:38, 23 June 2012 (UTC) [reply]
Ran a business with insects? Clarityfiend (talk) 23:15, 23 June 2012 (UTC)[reply]
Some Chiroptera guano "differently realitied" editor has started an article about the guy.--Shirt58 (talk) 12:04, 24 June 2012 (UTC)[reply]

Status of a request for a qualified expert to create a Wikipedia article on the concept of "new water". edit

To whom it may concern:

I made a request for an article on the subject of "new water", and supplied enough information so such a person could be found. Now I'm unable to find the request and the message I previously wrote. The following is what I supplied:

−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−

I am not qualified to write an article about this subject, but it is of extreme importance currently. I would like to request that a qualified writer, not pre-disposed to consider what follows to be the work of a charlatan in the water prospecting business, create the article.

In the 1960's a mining engineer, named Stephen Riess, discovered a water generating process within the Earth he called "new water". It was part of his management of mining operations in silver mining at high elevations in Nevada. Some of the mines he was associated with were experiencing flooding that could not be explained by the hydrologic cycle because of the high elevations in which the flooding occurred. I was fascinated by an article appearing in the Los Angeles Times and obtained the article from a library. A book was written called "New Water For A Thirsty World" by Michael Salzman, who interviewed Riess. Based on Riess' mining experience he began a business prospecting for water, that, among others, attracted the Sparklets Spring Water Co to drill a well for them near Ramona, CA. The well Riess created successfully produced water for the company. This was one of many successful water projects. At the time Riess also approached the State of California for an alternative to the Feather River Project as a much less expensive way to supply adequate amounts of water. His proposals were rejected.

Riess was an educated person, having received his engineering degree in Switzerland. I actually met with him and his wife in Ojai, CA in the early 80's with some friends, one of whom was a scientist for Hughes Aircraft. At that time he was in his 80's. During that visit I learned that one of his professors in Switzerland was Albert Einstein. He also explained that one of his professors in the petroleum engineering field showed how crude oil could be created in the laboratory, which explains the theories of some that "abiotic oil" exists, and is not the result of dead dinosaurs, something space exploration is confirming from the exploration of planets in our Solar system. He had created a successful well on his property on Sulfur Mountain Road, which is also at an elevation well above any explanations that traditional hydrologists can provide.

The reason I believe this article would be of great current interest is because of the nuclear disaster in Fukashima, Japan. The radioactive contamination has reached as far east as Philadelphia, PA, and is showing up in sea life, like the blue fin tuna, on the west coast of the United States. If an article, such as this, was created it should generate a great deal of interest in renewing the search for uncontaminated water anywhere that radioactive contamination has become a public health problem. In the book mentioned above there is a passage in the book about above ground atomic testing by the United States. This widely distributed radioactivity that was born by air currents across the Earth. However, the wells Riess constructed never became contaminated because they were not part of the hydrologic cycle. The current implications of this should be evident, and is why I believe an article created by a qualified expert, who is unafraid of criticism within his discipline, could draw widespread interest.

I have done some cursory research provided by others to help explain this request as follows:

http://ajph.aphapublications.org/doi/pdf/10.2105/AJPH.51.4.627-b

NEW WATER FOR A THIRSTY WORLDBy Michael Salzman. Los Angeles, Calif.: Science Foundation Press (73314 Ascot Station), 1960. 210 pp. Price, $5.95. This book projects a theory that: (1) there are everlasting supplies of new waters in little-explored, solid-rock fissures within the earth; and (2) they originate from chemical processes occurring there and are unrelated to the familiar ground water, dependent on insoak, which man conventionally taps to supplement surface supplies. These new waters, the author asserts, can be scientifically located and economically brought to the surface, even in deserts. Examples are cited. This would be a boon to our present dilemma -a rapidly closing gap between water demands and the fixed supply of the hydrologic cycle. Water pollution and its health implications are briefly discussed. Mentioned is "the constant pollution of our drinking water by hundreds of new chemical products whose effects on human health are totally unknown." The author projects a possible link between today's increasing chronic (cancer and cardiovascular- renal) disease rate and drinking water supplies. Apparently painstaking research went into the preparation of this thought provoking and somewhat convincing treatise. The effort was spurred by the work of Stephan Riess, a Californian. Riess formulated the "new water" theory and has gained attention in the press by drilling good water-producing wells where others had failed. Although Riess has been called by some "a charlatan, a witch, and a fake," the author is convinced that the Riess theory is authentic and that it can ex- plode certain established scientific and hydrologic principles if delved into with "open mind." Except for brief recitations in highly academic and scientific terms and formulas, this book is easily read by the layman. Salzman demonstrates a remarkable cross-knowledge of the earth sciences and believes that less narrowminded specialization could improve scientific achievement by chemists, physicists, metallurgists, mineralogists, and crystallographers. Certainly for each of these professions this book holds something of interest. Likewise, both professionals and students in forestry, soil, agronomy, and the water resource field will find this book readable and an excellent reference. The book documents in detail 198 references. GORDON MCCALLUM


Amazon source:

http://www.amazon.com/s/ref=nb_sb_noss/184-3038211-9982362?url=search-alias%3Dstripbooks&field-keywords=New+Water+for+a+Thirsty+World

New water for a thirsty world. (Paperback) by Michael H. Salzman (Author)


Nablus, Palestine: The city stands at an elevation of around 550 meters (1,800 ft) above sea level

This is the location of Jacob's well, which has been unaffected by sparse rainfall since its creation thousands of years ago. That is one of the other characteristics of these water sources, which is another way of discounting hydrology as a water source.

If anyone who reads this knows of a person that could contribute to this request, please contact them. Please know that statistical studies are showing that the Fukushima reactor failures from the tsunami are already showing evidence of increased cancer rates in the United States.

−−−−−−−−−−−−−−−−−−−−−−−−−−−−−

As I explained, I'm not an expert in this field, as are those at the links I supplied above. So I would like to follow the status of my request. Based on what I supplied above can anyone please locate what I previously wrote and provide a link to it. If no one can be found to respond as an expert on the subject I'll do my best. In the meantime I would like to follow the status of my request. — Preceding unsigned comment added by NewWaterWorld (talkcontribs) 18:27, 23 June 2012 (UTC)[reply]

Here is your edit: [1]. It looks like you unintentionally deleted large portions of the existing page when you posted, so were reverted some 6 hours later. Here's how it looked after you posted: [2]. Here's how it looked before you posted (which is also how it looks now): [3]. Try posting again, at that last link, but be a bit more careful not to delete anything else. StuRat (talk) 18:42, 23 June 2012 (UTC)[reply]
I reverted your original edit for the reasons that StuRat said. Also note that requests normally only include the name of the requested article and a few words on why, often with a link to a supporting source or two, not a long essay - it completely overwhelms the page, which is a concise list of requested articles. Mikenorton (talk) 19:07, 23 June 2012 (UTC)[reply]
Perhaps they could post a link from there to their talk page, where they would list all of the above. StuRat (talk) 19:57, 23 June 2012 (UTC)[reply]
That would be fine - unfortunately (in my view) the introduction at the top of the page does say "please include as much information as possible", but that's because people often just add a redlink with no other information at all. Mikenorton (talk) 20:39, 23 June 2012 (UTC)[reply]
Is there any data from drilling that support the "New Water" theory?, any peer review of said material? Electron9 (talk) 00:18, 24 June 2012 (UTC)[reply]
You may also be interested in juvenile water which is formed from magma. Graeme Bartlett (talk) 08:58, 24 June 2012 (UTC)[reply]

Would it be possible to dream with one eye open? edit

Real dreaming, with actual video, not just daydreaming. Sagittarian Milky Way (talk) 19:33, 23 June 2012 (UTC)[reply]

Maybe in complete darkness, or if totally blind, so the light wouldn't awaken then, although having an eye open might keep them awake even then. StuRat (talk) 19:58, 23 June 2012 (UTC)[reply]

Yes, it is possible. Not everyone sleeps with their eyes closed. Some people normally sleep with their eyes open, and there are some who have a condition called Nocturnal lagophthalmos, who have a type of facial paralysis. Both are able to dream. For an interesting story about someone with nocturnal lagophthalmos, read this: [[4]]. Dominus Vobisdu (talk) 20:10, 23 June 2012 (UTC)[reply]

"Video"? Evanh2008 (talk|contribs) 20:38, 23 June 2012 (UTC) [reply]
That seemed a rather elegant way of putting it, actually.
That video would not be in 3D then with only one eye open. Why not open both eyes for the full 3D hi def suround sound dream experience. SkyMachine (++) 21:59, 23 June 2012 (UTC)[reply]

Google the lyrics to Enter Sandman. μηδείς (talk) 20:50, 23 June 2012 (UTC)[reply]

I've been asleep and dreaming with both eyes open before. But not just one. It is a bizare feeling when you wake up because you know your eyes were open and that they must have seen things but you can't remember what they saw. 203.27.72.5 (talk) 23:33, 23 June 2012 (UTC)[reply]
I've been using Unisom in my fight to go back to 8 am wake-up but you wouldn't believe how sleepy it makes you if you don't physically exit the bed after waking up. After awhile it gets so hard to fight the sleep you might as well be fighting general anesthesia. You could sleep 4 hours more than you need (in several sections). (for some reason it's not really hard after you've left the bed) I thought if I kept at least one eye open I can't fall asleep but I became delirious. Causality is somewhat fuzzy at this point but eventually I was reading a nonexistant Cat in the Hat book in my dream (for some reason). Eventually the video feed from the brain was suddenly cut off and replaced with the eye feed. A bright sunlit bedroom. I'd managed to fall asleep with one eye looking at daytime. Sagittarian Milky Way (talk) 23:58, 25 June 2012 (UTC)[reply]
Being able to see things without being properly awake is extremely common. As is being able to carry out complex activities (e.g., finding alarm clock and then configuring it to shut up and not keep beeping) without being properly awake. --Demiurge1000 (talk) 23:44, 23 June 2012 (UTC)[reply]
I can personally attest to the latter issue with the alarm clock. It is exceedingly frustrating to wake up late for work and realise that you have switched off your alarm clock and have no memory of having done so. I am happy to report that the problem is now solved since I modified my alarm clock to add a key switch. I hide the keys in a different location each night and the requirement to engage my memory before I can switch off the alarm ensures that I am actually awake. Equisetum (talk | contributions) 09:49, 25 June 2012 (UTC)[reply]
None of that works for me; I just remove the battery from the alarm when I wake up, and then promptly go back to sleep without a memory of it. Gotta try some new method. Lynch7 16:25, 25 June 2012 (UTC)[reply]

If there are no pain receptors in the central nervous system, why do headaches hurt? edit

Topic says it all. ScienceApe (talk) 20:08, 23 June 2012 (UTC)[reply]

The simple answer is that, the blood vessels that run through the brain have nerves sensitive to pain. The symptoms of a head ache originate from them. As to why, you best ask a neurologist but id may has something to do with the release of prostaglandin ; (or in my case too much alcohol).--Aspro (talk) 20:27, 23 June 2012 (UTC)[reply]
Migraines are believed to be caused by internal bloodflow. But there are also the more common sinus headaches and muscle-tension headaches. μηδείς (talk) 20:47, 23 June 2012 (UTC)[reply]

I have a follow-up. Where do blood-flow headaches hurt? Is the sensation actually internal? (I only get sinus and tension headaches.) μηδείς (talk) 20:53, 23 June 2012 (UTC)[reply]

This is close to giving medical advice, therefore the only advice I will give is to take your check-book along to your quack doctor and ask him. If you're mildly computer literate there is a world-wide-web search engine called Google. That has thrown up this: [5] I won't say that simple meditation has been found to work better that drugs for tension headaches, as that would be medical advice and you quack (dam, why does me spell checker doing this?) will not like to hear that.--Aspro (talk) 21:15, 23 June 2012 (UTC)[reply]
What a rude, ill-considered, uninformative, and, frankly, hysterical response. I am not asking for medical advice. I don't suffer from blood-vessel caused headaches, so I do not know what they feel like. I am simply curious. My question, if I can make it clear, is, where does the pain seem to originate from for those people who suffer such headaches? μηδείς (talk) 21:39, 23 June 2012 (UTC)[reply]
You stated I only get sinus and tension headaches" Wikipedia:Reference desk/Guidelines/Medical adviceHow else could I have answered it?--Aspro (talk) 21:56, 23 June 2012 (UTC)[reply]
Yeah, I see how talking about quacks, giving me unsolicited medical advice on how to treat tension headaches, and giving a link that says nothing about where pain is actually felt is called for when I asked exactly what I meant, "where do blood-flow headaches hurt?" Please don't respond to me again unless you actually have an answer to my question. μηδείς (talk) 22:04, 23 June 2012 (UTC)[reply]
I have read the articles on headache and migraine. They do not describe where migraine pain occurs other than describing it as unilateral. Is there any information which describes this? μηδείς (talk) 22:24, 23 June 2012 (UTC)[reply]
Migraines can occur in many places. For example, my wife gets migraines in her tooth, which then shift up to her head to become a normal headache. In Oliver Sacks' book, Migraine, he describes a number of other odd body parts from which migraine can occur, such as (IIRC) the stomach. Before meeting my wife, I'd always assumed that migraine was just a synonym for "really bad headache", but it really isn't the same thing at all; the fact that they often occur in the same kinds of areas as a normal headache is misleading - a bit like a heart attack that feels like a sore shoulder. Matt Deres (talk) 01:31, 25 June 2012 (UTC)[reply]
Aspro, many of us don't need to take our cheque-books along to our doctors, since we have state-provided medical care. If you're having to bribe your medical professionals in order to get treatment, you may have a headache of a more general character than the others under discussion here. AlexTiefling (talk) 22:36, 23 June 2012 (UTC)[reply]
Alex, please read WP:SOAP. Aspro, please read User:Kainaw/Kainaw's criterion — Medeis is adding a comment to clarify the reason for asking; you can answer the question completely without providing a diagnosis, prognosis, or treatment advice. Nyttend (talk) 03:18, 24 June 2012 (UTC)[reply]
Thanks! Kainaw's criteria are actually quite brilliantly expressed. I was going to object that I was neither asking for a diagnosis nor a treatment if challenged again. I see I omitted prognosis, but am obviously not asking for that either. In any case, can anyone answer the question? μηδείς (talk) 03:46, 24 June 2012 (UTC)[reply]
I don't know about migraines, but I (thankfully rarely these days) get cluster headaches, a type of vascular headache. The pain always originates just behind my right eye, before radiating out over my temple. It's hard to describe any pain, and I can't put it any better than our cluster headache article, which says it is like having a red-hot poker inserted into the eye. The pain is definitely more "internal" than a tension headache. 92.20.237.148 (talk) 11:29, 24 June 2012 (UTC)[reply]

The following is medical advice but such obviously crackpot advice that only scientologists who don't read Wikipedia are likely to heed it. Their cult founder advised one to throw a headache out of one's own head into someone else's head. DriveByWire (talk) 14:09, 24 June 2012 (UTC)[reply]

Oh, as their seem to be a couple of sensitive hot-buttons out here, I wont bother to post more comprehensive answers, even though I have the time available now to take each one individually.--Aspro (talk) 18:53, 24 June 2012 (UTC)[reply]

Middle meningeal nerve
Meningeal branch of the mandibular nerve
Icek (talk) 19:02, 24 June 2012 (UTC)[reply]


I'm immune to headaches, I've never had a headache in my life. Even when I had a severe concussion, I didn't get headaches. This actually caused problems for me. When recovering from the concussion, I would not get any warning signals that I was using my brain too much. When I had done a bit too much early in the day, I would pay the price for that later in the day; I would have difficulties concentrating to the point of not being able to follow what someone was saying. I had to put up with this problem for half a year. Count Iblis (talk) 02:02, 25 June 2012 (UTC)[reply]

Interesting answers, including the one about marbles. I should have suspected there might be pain behind the eyes. I have had that sometimes with bad sinus headaches but not, thankfully, to the point of hot-pokerdom. μηδείς (talk)

Unless I missed it, nobody seems to have answered the original question, which is that generallly a headache involves the scalp skin and musculature. For instance, the "caffeine withdrawal" headache which appears to be a result of caffeine's effect increasing bloodflow, and the resulting restriction of bloodflow through the many blood vessels in the scalp when it wears off. AFAIK. As for migraines, however the connection with blood vessels in the brain, they appear to have much in common with epileptic seizure type stuff than regular headaches; thus the optical migraine which is actually painless. Gzuckier (talk) 03:03, 25 June 2012 (UTC)[reply]

Pre-amp for oscilloscope? edit

My oscilloscope is crumby and isn't sensitive enough for my needs even with max gain. Is there some way I can pre-amplify the signals (presently 2-6 volts) which are sometimes AC, sometimes DC? I don't know much about electronics. — Preceding unsigned comment added by 94.1.194.66 (talk) 23:12, 23 June 2012 (UTC)[reply]

So why does somebody without much knowledge of electronics use, or even own, an oscilloscope ? (Knowing how you use it might allow for better answers.) StuRat (talk) 00:18, 24 June 2012 (UTC)[reply]
I'm learning about electronics as a hobby and have a few circuit designs I want to try for dynamo-driven bike lights. I need the oscilloscope to better understand the designs and the effects of inclusion of certain parts. It's just a rubbish old oscilloscope off eBay. --94.1.194.66 (talk) 00:56, 24 June 2012 (UTC)[reply]
I don't understand why you would need to amplify signals in the 2-6 volt range. If you were talking millivolts or microvolts I could understand it. 2-6 volts should be ideal for an oscilloscope, if my memory serves me. Looie496 (talk) 02:08, 24 June 2012 (UTC)[reply]
I concur with what's written above. Virtually all oscilloscopes ever made have sensitivities in the range 1mV to 10mV per division or per cm, regardless of whther they are cheapies or professional lab-grade units worth a year's salary. Sensitivity worse than 50 mV would be very unusual. For a typical screen having a height of 6 to 10 cm, that means a signal only 10 to 100 mV will fill the screen. What you might have purchased in error (yours or the seller's) is not an oscilloscope but a "modulation monitor" intended for use by radio hams. These look like a very simple osciloscope, but have no internal amplifier, as they are intended to be driven by the transmitter output - so that the ham can tell whether he is overmodulating or undermodulating. If this is the case (make contact with a local ham if you need), I recommend you scrap it or sell it again on ebay. You could build an amplifier for it, but such an amplifier requies skills and experience. Keit120.145.65.23 (talk) 03:25, 24 June 2012 (UTC)[reply]
The oscilloscope is a Heathkit IO 102 which can be seen here http://www.youtube.com/watch?v=27s3QynquoI - I get a deflection of two small divisions for 6.5 volts. Edit: According to an old advert, this machine should be able to measure down to 30mV per cm. Furthermore, I get the exact same deflection from applying 1.3 volts as 6.5 volts (using NiCd batteries). Could the machine be damaged? --Seans Potato Business 11:38, 24 June 2012 (UTC)[reply]
You mean this advert? I agree that your scope appears to be broken. If you tried to amplify your signals using a laboratory preamplifier, you would probably exceed the input range of your scope and fry what's left of its vertical amplifier. According to that advert, the scope has a one volt peak-to-peak test output (might be labelled "1-V"). Try feeding that into the vertical input and see if you see a square wave. --Heron (talk) 12:26, 24 June 2012 (UTC)[reply]
Yes, the compression of signals to only two divisons indicates a fault in the vertical amplifier, and a preamplifier will definitely not help. Since you are new to electronics, and repair by a commercial business will cost far more than a new oscilloscope of this class, I recommend that you make contact with a local ham radio chap. Not all hams have sufficient skills to diagnose faults in electronic circuits, but whoever you do contact will know another ham who does. The cost of parts to fix it may well be of the order of 20 cents - a few dollars if you are unlucky. Each country has its own ham radio association (eg ARRL in the USA, RSGB in Britain, WIA in Australia) - they would be a good starting point if you don't know any hams. Most hams will try to be very helpful to anybody starting in electronics as a hobby. Good luck. Keit120.145.65.23 (talk) 13:18, 24 June 2012 (UTC)[reply]
The first step to repairing your oscilloscope is to get a copy of the circuit diagram which you can do here. DriveByWire (talk) 13:57, 24 June 2012 (UTC)[reply]

There is an email listserve for heathkit equipment which often discusses repair of such things. (Replacing old electrolytic capacitors seems to be a constant theme) and I will tack the how to get to it on here pretty soon when I get back to my regular email. Gzuckier (talk) 02:56, 25 June 2012 (UTC)[reply]

Ok, it's
Heath mailing list
Heath@puck.nether.net
https://puck.nether.net/mailman/listinfo/heath

the majority of the posts are regarding old Heath ham equipment, but there are plenty of posts regarding fixing other equipment, buying and selling, manuals and circuit diagrams, etc. etc. etc. Without a doubt somebody will be able to help you with the scope. Gzuckier (talk) 02:22, 26 June 2012 (UTC)[reply]