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October 6

SAM system guided by phased array radar whose components are distributed over a wide area

Why don't countries like Iran who have difficulties acquiring conventional air defense systems like the S-300 build their own systems using modern electronics? It seems to me that you can quite easly build a phased array radar that consist of a large number of small antennas spread out over a big area. Such a radar system cannot be taken out by a few airstrikes (it will remain functional if some fraction of the antennas are taken out). This radar can guide missiles toward aircraft and these missiles don't need to be located near the phased array antennas. It seems to me that such a system would be less vulnerable than the S-300 system (which needs to be protected by short range SAM systems). Count Iblis (talk) 03:22, 6 October 2013 (UTC)[reply]

I can't answer the question directly, but our articles on bistatic radar, multistatic radar and passive radar would be relevant. Acroterion (talk) 03:33, 6 October 2013 (UTC)[reply]

Is there any reason why Iran could not master the technical details of a large area phased array radar? As an engineer myself (and who has met refugee Iranian engineers trained in the USA pre-Islamic Revolution), I don't think so, technically. And who knows what secret stuff they may have in the pipeline However, what gets developed in various countries depends on many things, not just technical know-how.

Firstly, the field is specialised, and you need not just good engineers but engineers who are keenly interested - otherwise they just won't have the specialist skills, which take years to acquire. An interesting example is the World War 2 developement of radar. Japan tried to develop good radar equipment without much success a they had no enginners interested and thus having acquired specialist knowlege. Germany had some success. Great Britain had considerable success, as it happend they had scientists and engineers already interested in the technology, ironically having learnt of a key development (magnetrons) in pre-war Japan. USA also had success due to their immense industrial might. Some of the best WW2 field portable radar equipment was developed independently in Australia - it just so happened there were a handfull of chaps with the right skills.

Secondly, what gets built and what doesn't, depends on how well the political leaders (invariably in any society the people who are technology illiterates), who control the money, understand things. It can happen that they just don't think an advanced technology can be developed locally. An example of this is the development of advanced large bomber aircraft in the USSR imediately after WW2. Their leaders in the Kremlin clearly understood the need, but didn't think their aircraft industry could come up with the goods. So they ordered their aircraft industry to produce exact copies (Tupolev TU-4) of the American B-29, based on what they could learn from 3 captured examples and a great deal of espionage. The USSR was a fully metric country, and the USA of course non-metric. So, even though the USSR was already able to make aluminium alloys as good as any (in metric sizes) and all manner of parts, and engineers as good as any in the West, they ended up constructing a complete set of non-metric industries, requiring immense investment and training, just so they could make the B-29/TU-4. Clearly, it would have been cheaper and better to design their own bomber completely from scratch, based on indigenous materials & parts, rather than go for an exact copy. But Stalin didn't realise that. After his death, they designed their own quite succesfully.

1.122.56.195 (talk) 11:58, 6 October 2013 (UTC)[reply]

I agree it seems a relatively straightforward task to design a multistatic array and use it to control the SAM. Some idle thoughts (1) you still have emitting stations which can be taken out in all sorts of cheapish ways. (2) A multistatic array is inherently more expensive for a given level of performance than a monostatic one, so the aggressor has already scored a partial kill since fewer systems can be built for the same money. (3) maybe stealth isn't that big a threat, it may have been over-sold by its proponents. I'm not convinced that any of those is right but they are possible. I'd certainly expect some country with a large supply of technology graduates and expertise in electronics and telecoms to develop such a system if those objections don't apply. Greglocock (talk) 02:03, 7 October 2013 (UTC)[reply]

The wiki nannyware won't let me link, but a google search on problems with implementing multistatic radar arrays came up with loads of hits. Computational load comes up as a big part of the issue which is surprising to me, but the MIMO systems I analyse have relatively high S/N ratios (50 dB at worst). Greglocock (talk) 03:01, 7 October 2013 (UTC)[reply]

Interesting! I was thinking about using this to deal with an enemy that would likely gain total air superiority like in case of Libya against NATO. If Gaddafi had bought a few S-300 systems these would still not survive indefinitely under the NATO attacks. They could be engaged using misslies from beyond its range or by aircraft flying in low to attack it directly (that depends on how well it is protected by short range SAM systems).

But if instead of conventional radar systems you have a huge number of dipole antennas spread out over a huge area, there won't be good targets for NATO to hit to destroy the SAM system to make the airspace safe for them. Count Iblis (talk) 14:37, 7 October 2013 (UTC)[reply]

Not too sure if this might not be better on my or your talk page, but the individual receivers and transmitters aren't what you'd hit, you'd go for the computing network and guidance radio, by choice. The computers are working all the time by necessity so they are the easiest to find. Greglocock (talk) 22:24, 7 October 2013 (UTC)[reply]

Depending on the radars' location, they could also be destroyed or sabotaged by commando teams, as the Egyptian SAMs were during the Yom Kippur war. 24.23.196.85 (talk) 05:57, 8 October 2013 (UTC)[reply]

Anomolous nature of LiAlH4

LiAlH₄ is a reducing agent. then why does this reaction occours ?

    CH₃                                  CH₃
    |           LiAlH₄                   |           
H₃C—C—CH₃     ——————————→            H₃C—C=CH₂
    |
    Cl

— Preceding unsigned comment added by Sa29nchit (talk • contribs) 15:07, 6 October 2013 (UTC)[reply]

LiAlH₄ is a Lewis base and a nucleophile. When it attacks certain types of molecular structures, for example, a carbonyl, the effect is a reduction of them. It's not a pure "donate loose electrons" type of reducing agent, the definition students are often taught in lower-level courses. But even your reaction is a reduction in a simple sense: the "H⁺" that is lost from the organic structure becomes a neutral hydrogen. Always important to look at all of the products and byproducts, not just the main organic structure. I fixed the ASCII-art layout to be what I think you meant: the HTML tags especially were not considered when using "space" to align the lines. DMacks (talk) 17:06, 6 October 2013 (UTC)[reply]

Islamophobia

Is "islamophobia" listed or mentioned as a mental disorder in DSM-5? --72.66.30.115 (talk) 17:21, 6 October 2013 (UTC)[reply]

No. AndyTheGrump (talk) 17:25, 6 October 2013 (UTC)[reply]

If if were a mental disorder, would it be listed in DSM-5? --72.66.30.115 (talk) 17:33, 6 October 2013 (UTC)[reply]

Why not? What hasn't been in or out of that list of quackery pandering to big pharma? Myles325a (talk) 03:41, 8 October 2013 (UTC)[reply]

Wikipedia does not provide answers to hypothetical questions. AndyTheGrump (talk) 17:39, 6 October 2013 (UTC)[reply]

(edit conflict) Answers accepted. (But the right answer to the second question was: very probably yes.) Thanks, Andy. --72.66.30.115 (talk) 18:11, 6 October 2013 (UTC)[reply]

As Andy says we cannot answer that hypothetical, but based on its ommission from DSM-5 we could say that "Islamophibia is not a recognized mental disorder in DSM-5" (if you actually want to say that in a wikipedia article, you'll perhaps need a secondary source making that observation, in order to avoid WP:OR).

More broadly: Not being a recognized mental disorder in a DSM does not mean that the concept is itself invalid or fictitious. For example, per my search, DSM-IV does not have a listing for "sexism" or "racism" but you'll be hard pressed to convince many that those phenomenon do not exist. Abecedare (talk) 18:01, 6 October 2013 (UTC)[reply]

Thank you, too, ABCDare. (except that racism and sexism aren't mental disorders). --72.66.30.115 (talk) 18:11, 6 October 2013 (UTC)[reply]

While political correctness is? μηδείς (talk) 21:09, 6 October 2013 (UTC)[reply]

"Islamophobia" is normally used to mean an ideology. As Phobia#Terms_for_prejudice explains: "A number of terms with the suffix -phobia are used non-clinically. " That's the same as being communist. Another different thing would be having an OCD with Islam as the object of obsession. OsmanRF34 (talk) 21:07, 6 October 2013 (UTC)[reply]

Without touching on Islamophobia, but rather addressing the OP's follow-up question If it were a mental disorder, would it be listed in DSM-5?: What is or is not a mental disorder is a matter of professional judgement, and the DSM's inclusion or exclusion of something represents the professional judgement of some, but not all, respected professionals. So there's no way of compiling an exact objective (non-judgement-based) list. So what many people do is perhaps the next best thing: they go by the DSM. If we go by the DSM in defining what is or is not a mental disorder, then the answer to If it were a mental disorder, would it be listed in DSM-5? is tautologically yes. Duoduoduo (talk) 21:18, 6 October 2013 (UTC)[reply]

So are other famous phobias (agoraphobia, arachnophobia, acrophobia) and countless more one reads about) individually and specifically listed in the DSM mentioned, or are they subsumed in some general condition describing anxiety and behavioral limitations in the presence of or when thinking about some stimulus to which the individual is sensitive? Edison (talk) 23:32, 6 October 2013 (UTC)[reply]

Any phobia is typically going to be a mental disorder in cases where it overwhelms the individual's ability to conduct a normal life. A lot of Christians and Jews are wary of Muslims. It's fair to say that a lot of Muslims are going to be wary of Christians and/or Jews. That doesn't make it a mental disorder. However, if someone convinces himself that a given group is "out to get him", despite the lack of any such evidence, and then goes into a place of worship and shoots everybody, there's a good chance that guy has a mental disorder. ←Baseball Bugs ^{What's up, Doc?} carrots→ 00:17, 7 October 2013 (UTC)[reply]

We have the DSM5 article, the table of contents is at [1] ... I don't see anything about Islamophobia or other obvious "hate" or "religion" based terms. (If someone wishes to enlighten us further, I notice that The Pirate Bay tracks a torrent for it... I haven't checked on relative risks of book downloads lately, but I don't hear much about it in the news) I wonder if psychiatrists in Islamic countries diagnose people who burn Korans, blaspheme Muhammad, or attempt to proselytize Christianity as having conduct disorder? Whereas I suppose followers of Islam or other banned religions in countries that prohibit them might be diagnosed with it? But I don't really do well at understanding psychology. Wnt (talk) 04:14, 7 October 2013 (UTC)[reply]

Something like that, in Saudi Arabia - 'deal with reports of students making fun of Islam's rituals or discussing subjects and ideas that violate Islamic law through "behavioural adjustment and life-skills sessions"' Card Zero (talk) 20:36, 7 October 2013 (UTC)[reply]

Here's a good model for calling islamophobia a disease, rather than a political epithet: Political abuse of psychiatry in the Soviet Union. μηδείς (talk) 04:28, 7 October 2013 (UTC)[reply]

I suspect that most of you are sort of missing the joke. Some people love to make up names of specific phobias, more as linguistic trivia than as psychology, "ailurophobia", "triskaidekaphobia", etc etc ad tedium. There's no real value in distinguishing these, but it's a fun game for some people, along the same lines as "a murder of crows". The OP is trying to fit "Islamophobia" into the same mold, either as humor or to make some sort of point, I'm not sure which. --Trovatore (talk) 04:33, 7 October 2013 (UTC)[reply]

I fear I am missing the joke as well. I could see if this question were at the language desk looking for an etymology. But the term has no medical origin. It's used to conflate certain ideologically political positions like support for Israel with lunatics who shoot at Sikhs because they wear turbans. μηδείς (talk) 04:45, 7 October 2013 (UTC)[reply]

Hmm, making stuff up, eh? Like having an irrational fear of instant replays, "Slomophobia". Or of the moons of Mars, "Deimos-and-Phobos-phobia". Or pretending to be afraid when you're not, a "fauxbia". Fear of the Irish, "O'phobia". Or for that matter, fear when I slam the door - hence, "I-slam-o-phobia". ←Baseball Bugs ^{What's up, Doc?} carrots→ 05:14, 7 October 2013 (UTC)[reply]

Trovatore, the OP wasn't trying to be funny or playing games; he was just asking for someone to look something up for him. He had boldly stated at the NPOVNoticeboard: [the word islamophobia] "is as phony as a three dollar bill—there is no such mental condition as an irrational fear of Islam" and the next commenter asked for a reliable source for that assertion. --72.66.30.115 (talk) 05:35, 7 October 2013 (UTC)[reply]

Oh, so then it was the second possibility, "to make some sort of point". But it's frankly sort of a silly point, because the term "Islamophobia" is not intended in that sense at all. It's usually used in the sense of "bigotry against Muslims", and there is no implication that it's a mental disorder. --Trovatore (talk) 06:18, 7 October 2013 (UTC)[reply]

On this page I asked a simple question. On the WP:NPOVN page I agreed with the AP and Salman Rushdie. Does that clear up your confusion? --72.66.30.115 (talk) 06:41, 7 October 2013 (UTC)[reply]

The reason for describing it as "phony" is straightforward—it appears to be the name of a mental disorder, a phobia, but turns out to be no such thing. --72.66.30.115 (talk) 17:21, 7 October 2013 (UTC)[reply]

This isn't all verbal mockery. Remember, "Islamophobia" follows on the heels of "homophobia", which in turn presumably has its roots in "homosexual panic", an actual psychology concept used most disreputably to try to provide a defense, even a justification, for people attacking and killing gays. The creation of the term is indeed a rhetorical coup, that confuses fear and hatred, irrationality and vehement rational rejection. (It is continued even here by various categorizers here and at Commons who classify Islam and Judaism, but not Christianity, as religions you can have "racism" against) Wnt (talk) 17:48, 7 October 2013 (UTC)[reply]

The term "phobia" gets used colloquially in ways that don't qualify as mental illnesses. As with words like "paranoid" or "schizoid" or just plain "You're crazy!" ←Baseball Bugs ^{What's up, Doc?} carrots→ 21:18, 7 October 2013 (UTC)[reply]

*http://www.myfoxny.com/Story/23636176/russia-protester-gets-forced-psychiatric-treatment μηδείς (talk) 17:16, 8 October 2013 (UTC)[reply]

Religious experiences have been linked to temporal lobe epilepsy, see here. Count Iblis (talk) 17:25, 8 October 2013 (UTC)[reply]

Sal ammoniac for soldering and "tip refresher"

I'm not particularly skilled in soldering (electronics). Sometimes the soldering tip blackens, particularly if I'm using a soldering gun. I was advised that sal ammoniac is useful in tinning a tip but with my soldering gun it seems that any progress I make on one side of the tip is negated by the blackening on the reverse. What chemical reactions are occurring? Does it matter if the sal ammoniac turns brown or even black? Should I try to remove the black deposits from the sal ammoniac? What is their chemical composition? I bought "tip refresher" which is somewhat expensive per unit mass. That product eliminated the black deposits on the tip and made it shine like new but it didn't take long to start to turn brown. If tinning with solder is required to protect the tip, why wipe it off again using a wet sponge? Does it matter if the sponge has turned a dark grey (presumably a deposition from the tip)? — Preceding unsigned comment added by 2.97.26.56 (talk) 19:25, 6 October 2013 (UTC)[reply]

Sal ammoniac is electrically conductive, so I would not use it on a soldering iron to be used on electronic circuits, as it could cause unwanted conductive paths if it got on a circuit board or bridged between terminals. It is better suited as a flux for stained glass lead or other crafts. I get a soldering iron hot then remove deposits with a wet sponge and reapply electronic solder (tin-lead alloy with rosin flux) to leave a shiny coat on the iron when it is stored.. The wiping removes oxidation products and dirt. Here is a soldering guide from Radio Shack [2] and one from the Weller soldering iron company via electronics seller Digikey: [3]. The Wikipedia article Soldering iron has a section with a "how-to" of cleaning, and it says that newer lead-free solders are more of a challenge as to keeping the tip clean. Acid core flux is good for plumbing, but bad for electronics use, since it can corrode the PC board traces and provide unwanted conductive paths: [4]. Edison (talk) 23:26, 6 October 2013 (UTC)[reply]

In any case, soldering guns should not be used in electronics. Several decades ago they were sometimes by radio and TV servicemen on tube based equipment (which was more tollerant of too much heat) repaired in people's homes, due to the almost instant heating, but never by properly trained technicians doing high quality work on professional equipment. The advent of precision temperature controlled irons such as the Weller TC-5 about 40 years ago rendered soldering guns obsolete in electronics, as they heat fast enough anyway. Soldering guns depend too much on the skill of the operator, and it is all too easy to damage parts while at the same time making poor quality joints. Use a temperature controlled iron with an earthed tip designed especially for electronics, use cored solder designed for electronics, and keep the tip clean with a wet sponge, and you will after a little practice have very little trouble. Not with tip discolouration or corrosion, not with damaging parts, nor with poor quality joints. In my experience, it takes very little time to teach school kids to do excellent work with the right tools. Nearly all master it with their first simple project.

Wiping with a wet sponge normally leaves a smooth shiny solder surface on the tip. If it doesn't, it is because the tip has been ruined by too much heat, cleaning far too infrequently, or using the iron for other purposes such as melting plastic. Or from long use making thousands of joints. 1.122.56.195 (talk) 23:59, 6 October 2013 (UTC)[reply]

Agree with the above. Just get yourself a nice temperature controlled soldering iron and a good illuminated magnifying glass stand and you'll produce nice joints and not burn stuff on the tip. Using a soldering gun for electronics is like using a hacksaw instead of a fretsaw for cutting out a pattern. Dmcq (talk) 07:29, 7 October 2013 (UTC)[reply]

I question the blanket statement that soldering guns were "never by properly trained technicians doing high quality work on professional equipment" and that they were only used in customers homes. Some joints in tube equipment took a significant amount of heat to get to proper soldering temperature, and a soldering gun could get it hot and get the wire or component lead soldered or unsoldered efficiently without overheating. Also the tv tech generally took the set to the shop if component level troubleshooting and soldering in of new parts was necessary (as opposed to tube replacement or adjustments. It was not reasonable to flip a TV chassis upside down on the customer's living room floor to start soldering in new parts, after hauling in signal generators and other testing equipment. Edison (talk)

You've obviously not worked in TV, radio, and radiogram repair in the 1960's and earlier. I have. After completing university after several years in TV and radio repair I became a profesional engineer. I can assure you soldereing guns were never used by properly trained techs working on professional equipment.

There were a few sets that were notoriously bad from a serviceman's access point of view (I remember the first Philips set available here that was a right cow of a thing), but in general, they were repaired with the chassis in more or less situ in teh customer's home. Different brands had different ways to give you access. On some with metal cabinets (the ones with a fake wood or fake textile covering), you lifted off the entire cabinet from the base plate upon which the chassis sits. On others, the chassis was on a hinged arrangement, with the various leads just long enough to let you (after removing the back) swing it out while it is still operable. Nearly all faults in electronics, then and now, are catastropic, in the sense that the set works well, or it is seriously unusable by the owner, due to a component failing completely (apart from low emission tubes). So nearly all faults were diagnosable by multimeter. I fixed over 90% of sets within minutes in the customer's home, with nothing more than a few hand tools like pliers and screwdrivers. a soldering iron, a multimeter, and experience.

Sets back then were designed somewhat empirically, even by major manufacturers. In consequence each model had its own set of common faults. Got a 1960 to 1964 HMV with an inoperative vertical oscillator? - it's the blocking oscillator transformer open circuit nearly every time. Got a Pope or Radio Rentals ("rent now buy later") with a blank raster? It's the video detector diode nearly every time. A GE 11" portable with compactron tubes? All sorts of weird symptoms were almost always due to the electrolytic can giving up (This set had all electrolytic capacitors in one large can). The 10% that did need a sig generator and/or CRO did get taken back to the shop, as did uncoopertive intermittents (customers get worried when you start banging their set with something hard, and it can take too long).

Customers often really didn't like servicemen taking the set away. The woman would wring her hands and moan "oh!, I was so looking forward to the serial tonight" / "Oh no, my husband has been talking about the game all week" / "My grandchildren are coming to stay with me - I need the TV to keep them amused - couldn't you please please try something and just get it going? I don't mind if the picture isn't perfect. Its for the kids."

And practically the only time you ever needed to do an alignment, the only thing requiring specialist test gear, was when some idiot owner (such as a beginner electronics hobbyist or radio ham) has had a go himself. You could get away with using a soldering gun in TV & radio repair, but only the cowboy types used them. If you worked for a dealer they generally wouldn't allow it. In this country there was an alternative to the gun type - the Scope and Birko brand carbon element soldering irons - they would heat in seconds but they were as bad as the gun types. Every where I worked they were banned.

— Preceding unsigned comment added by 1.122.124.206 (talk) 00:43, 8 October 2013 (UTC)[reply]

We can agree to disagree on this. Your personal experience of soldering things into sets in the customer's living room and somehow having good access to the underside of the chassis with the set upright is certainly your experience, but the practice was not universal. Lots of sets went into the shop for bench repair. Edison (talk) 14:53, 8 October 2013 (UTC)[reply]

You write crap, about things you clearly know nothing about. The very earliest TV's had skirted dish chassis with the tubes upright on top, and the passive parts underneath, like a 1930's or '40's radio. But from the 1950's very few TV's were built that way, for two reasons: a) the advent of high deflection angle CRT's, driven by the marketing need for the lowest possible cabinet front-to-back dimension, also forced manufacturers to install the chassis as a flat plate with a hole for the CRT neck to poke through (or two flat plates - a left and a right), installed vertically behind the CRT with the tubes horizontal poking rearwards; b) installing a flat plate chassis vertically facilated servicing, regardless of whether repaired in the home or back at the shop. Usually they were hinged at the bottom, or hinged at one side, unless they were small portables. To repair a metal cabinet set you generally had the option of lifting the cabinet upwards and off the set, leaving the "works" exposed on its base plate on its legs. If a wooden cabinet, or on metal cabinet sets also, typically you removed the back (by undoing a few screws), removed a couple of screws holding the chasis in situ, and either swung the chassis down, or to the side, as I said before.

Think about it. A tube TV set was never that complicated. The time taken to diagnose and identify the crook part, and replace it, was typically of the order of minutes. 15 minutes tops for hard faults on the less common sets. It would take the serviceman typically a lot more to drive to the customer's home. So, cost of fixing in the home is driving there, average 20 minutes, fixing it, 5 minutes, total 25 minutes labour. I've not counted a return time because mostly there isn't - you went directly from customer to customer. Compare with fixing in the shop: driving to customer's home, 20 minutes, take set into van, 5 minutes, drive back to shop, 20 minutes, fix in shop, take into shop, fix, and return to van, 8 minutes, drive back to customer, 20 minutes, move set form van into housr and show customer it works, 5 minutes: total 73 minutes labour. Not consecutive times of course, and not necessarily the same chap doing each bit. Clearly, it is a heck of a lot cheaper to fix as many sets as possible in the home. Incidentally, I was taught that for the special caes where it was necesary to bring it back to the shop, if the set was a wooden cabinet job, we removed the chassis from the set and just brought back the chassis. If you took the whole thing, it was heavier (might need two people to comply with OH&S requirements), took up too much room in the van, and you'd have to be lucky not to scratch or dent the nice varnish. TV sets back in the tube days were the family pride and joy, purchased on time payment, and lovingly polished each week by the houswife.

Each morning, or last thing the day before, we typically drove to the depot/shop and were given a list of names and addresses. The call taker got the set brand, and model or approximate year purchased if possible, and a very basic description of trouble (no picture? no sound? or bad picture or sound? bad on one channel only or on all channels? Any smell or unusual noise?) for each address. You loaded the van with parts to suit every vaguely likely fault for the brands etc listed, then spent the whole day going from customer to customer, never returning to depot/shop until the next day, if possible. About 70% + of parts would cover almost all faults in all sets in any case. You always had a full range of tubes in the van, but never CRT's, CRT's being big and heavy, and failures very rare. Tuners were replaced on a reconditioned basis, so you carried a range of tuners in the van. A good serviceman allied with a good route planner would fix about 12 to 15 sets a day. If he took most of them back to the shop, he would have to make individual trips, or if he just went back to the shop at the end of each day, he'd need a bloody great truck instead of a van.

1.122.124.206 (talk) 15:39, 8 October 2013 (UTC)[reply]

Ah, those were the days where they not 1.122.124.206 . Do you remember customers diagnosing that the TV “had gone on the blink” and when you got there - in the middle of summer- they had their curtains closed in order to see the latest episode of “I love Lucy” ( personally I preferred 77 Sun set strip) but now-days CRT's last ten years or more. The discussion appears however, to to have gone off topic.

I remember lots of things. In the TV repair game, you needed 20% electronics knowlege and 80% diplomacy, sales, and psychology skills. You'd get on your day list things like: "Mrs Brown, 123 Wheredat Street, 1961 Admiral, scratchy/tinny sound, picture ok, same on all channels." "Scratchy/tinny sound" was usually customer-speak for high harmonic distortion and/or weak volume. You'd expect either a weak audio output tube (~$3), weak grid capacitor (~$0.10), or a crook cathode bias (~$0.15). She probably knows a neighbour who had crook sound and was charged 25 minutes callout and labour plus $1.50 parts. When you get there the sound is crook because one of her kids repeatedly thrust a knitting needle through the speaker cone. But that's ok as a new speaker will be only around $8. But the picture is really bad, obviously had got that way over a couple of years or more. She's got used to it, thinks it is normal. All 3 IF tubes are sick and the line output tube is on its last legs. Some electrolytics are also sick and about to fail completely. The tuner's had it, only works on Channel 2, but she didn't know as she only watches Channnel 2. Total labour would be 20 minutes, total parts about $45. As a serviceman, you have a choice: You can just replace the crook speaker - 5 minutes labour and $8. She'll be happy but a few days later her brother will visit and tell her you must be an idiot because the picture is so bad and it doesn't work on channels other than chan 2. Or you can tell her you're going to charge 20 mins labour and $45 parts - she'll then think you are a crook. 120.145.63.186 (talk) 01:31, 9 October 2013 (UTC) [reply]

How right you are. When, as a young thing, and not understanding psychology or anything, I used to scratch my head about this picture/audio issue. Looking back, I think many people of that era bought just bought primarily a wireless which also happened to show moving pictures (radio being more familiar to them than TV in those days) so sound 'was' the more important quality. The customer was always right, as he/she paid the bill. Once my boss got me to see that, the job got a lot easier. I.e., Don't try to get the TV back to the factory standard that YOU know you can achieve , just-please-the-customer. It was no longer primary a technicians job. More than once, on a home visit, I felt obliged to to dig a hole in the backyard of some widow, so that a much loved but deceased pet could be interned (although usually, I was asked less memorable things like unblocking a hand-basin). But what the heck. In those days, an elderly widow was held in more esteem by her neighbours and friends so referrals to your repair business from her -because she valued you- brought in even more work. The compartmentalize attitude of the modern service-man leave me with no feeling that I what to call on their company ever again. --Aspro (talk) 15:47, 9 October 2013 (UTC)[reply]

So to the the OP asking the question:

Speaking as not a TV repair man but some one that has worked in R&D where the quality of my soldered joints where all important. I'll give you the benefit of my experience.

(1) Sal ammoniac is for tin-bashers. Very good for what their are doing but they wash it off because they know it is corrosive. Sal ammoniac is a no-no for electronics. (2) For electronic one needs a good non corrosive rosin flux. (not the halogenated type -that’s carcinogenic. (3) Others have posted and recommended a 'Weller' soldering iron. They may cost more but they are good. After all, do you want to repair a Roles Royce with the tools of a black-smith. A unjacketed copper tip iron will give you poor service. (4) One poster belittled Radio Hams. Should you wish to learn good soldering practice – contact one. Good soldering is easy to learn. Monkey sees Monkey learns. (5) Weller has 'iron clad tips. Most people think this means that the tip does not corrode as fast as a copper tip. Yet, it also has the advantage that if you have a flying lead (in say a HiFI), copper from the tip has not diffused into the soldered joint so it will not work-harden to to a 'dry-joint'. (6) A good non corrosive rosin flux does not need to be removed. We did but we were doing exacting stuff.

By all means, make an effort to contact your local Ham radio enthusiasts. They can lead you to places where you can buy (for affordable sums) the tools that you covet. They can also pass on tricks of the trade, like putting ones hand in ones pocket when you press the cap of the CRT line output tube back in to position. (that was a joke by the way ! Just said it to enforce that just because they are amateur doesn't mean to say they don’t know what they are talking about). Where as certified TV repair man ex-perts (drips under pressure) will reply... Oh. I'll will have to take this back to the workshop (because I have not been taught to fix things at this level). What is this US of A thing about being certified? Mental patents also can be certified. To the home customer the important thing is: I don't care if you have enough degrees to get a job as a laboratory thermometer …. -Can you fix it?! Sadly today, when I got two different TV 'repair' men to look at my Sony (yes, I know but I like the quality of the picture) they both gave wildly different diagnosis despite my telling them at the outset which circuit had gone. I know the the next generation is our future but in a agreement with 1.122.124.206 I some times despair with these know-it alls. In the good old days, kids grew out of it after seventeen, mind you the were getting married by then and had to wise-up pretty quick to their responsibilities. Now we have a generation of middle age adolescents.--Aspro (talk) 18:49, 8 October 2013 (UTC)[reply]

What are "tin-bashers"? 2.97.26.56 (talk) 19:49, 9 October 2013 (UTC)[reply]

A vely gwood kwestion. I donn't knoe if you have hurd ab0ut wikipediadia but they (as always) have an article about it:

“Sheet metal workers are also known as "tin bashers" (or "tin knockers"), a name derived from the hammering of panel seams when installing tin roofs.” [5]--Aspro (talk) 23:22, 9 October 2013 (UTC)[reply]

If you can't get someone to show you how to solder then follow this: http://www.google.com/url?q=http://www.goot.co.jp/gootpdf/sales/YUKA/HOW_TO_SOLDER_0902E.pdf&sa=U&ei=j-ZVUtucPIal0AWrnYCYDg&ved=0CFYQFjAM&usg=AFQjCNEUjaszCpMcQuiYmFAmf5T7PKpeHg --Aspro (talk) 23:51, 9 October 2013 (UTC)[reply]