Diagnoses

[km6xz]

Maybe you are hanging out in the wrong bars.....good bars have a ratio of 60-65% young women to men.

If they have less the whole atmosphere becomes more nuts with guys acting like asses, and bars with lower than 50% women end up being only for those wanting to get drunk. When a new bar opens I usually visit to see the atmosphere and have been very accurate in my predications of their success or failure within the first year. Here, English style pubs are very popular with women since the norm is being a very social place where everyone talks with each other and there is very little hunting by desperate guys making it uncomfortable for women. There are some really nice bar towns in the US...San Francisco, Boston, Seattle, Austin, Portland, Charlotte, (Back in the day) New Orleans etc where even small working class neighborhood bars can be good social atmosphere and have good food, good music, and no bar fights. I have been going to bars for decades here and never seen a fight in a bar, always fun and always lots of beautiful friendly well educated girls. My visits to UK in recent years suggests that more pubs are going out of business than replacements opening. East Berlin is a great bar city. I guess I have been in bars in all 86 countries I have visited, they are great places to very quickly get a feeling for the local culture and find someone to talk with.

[km6xz]

It is interesting that in the Lobby there are some who post there to get a battle going yet I have not seen any technical contribution from those who are rabidly right wing. Do they only post on forums to get people riled up?
I am moderator of a large camera and photographer forum that has paid membership(385,000) and it is very civil but there is a quick response from moderators when someone going off the wall. There is a quick cancellation of membership with no refund for repeat offenders on our forum however.
There is a larger open forum with 3 times the members and every thread is an argument and the general attitude is negative and attempts to criticise every new product or topic or example. Since it had so many readers and influenced so many buyers Amazon bought it. Here, a thread could be not getting help in the future so with every civil forum there is probably some form of carrot and stick, even if it is a threat of simply becoming unwelcome.

[Leo_Gnardo]

Maybe you are hanging out in the wrong bars.....good bars have a ratio of 60-65% young women to men.

The ratio's reversed around here. But I found a way to get the women's attention, they're all attracted and want to talk to me . . . I disguise myself as a cell phone.

[km6xz]

The team approach works when there is a common goal and broad understanding of a framework, such as a sports team. But in troubleshooting the mix of haphazard suggestions with no other foundation that once the poster say a similar symptom and doing "xyz" fixed it seemed to resolve the symptom. I read some of those posts but seldom post on those where lots of novice type suggestions introduce confusion and possibly further damage. The poster has to be aware that some of the advice is not thought out and might be someone just repeating an internet rumor. I think most of those who write to me privately do so because of the confusion the various theories posted create. If working one on one the problem just about always get identified quickly with no additional damage to the unit.
Some cite the "learning experience" as why having a goose chase of conflicting actions or theories but it is also introducing a lot of really bad habits or troubleshooting practices. The longer a thread becomes it seems the slower the resolution and more likelihood of further damage.
Trouble shooting is not a random testing or prodding process, there are good and bad styles, but all effective methods are logical.
A bare minimum of test gear should be available if an owner wants to repair their own unit. For amplifiers, a DMM, a steady signal source of known frequency and level, a decent soldering iron, a lamp current limiter of current metered variac, a dummy load (for tube amps) and an oscilloscope. Without these, a repair is going to take longer, and less accurate in a remote diagnosis. If one can't borrow a scope, they would not be working on their own amp, and none of us should encourage them to risk their investment and value in their gear that could be damaged easily.
In a commercial repair shop the most valuable information needed to effectively solve a problem is an accurate description of the problem and how to reproduce it. In my own shop, I had a couple girls at the counter who really know how to extract this information or have the customer demonstrate the problem. About 25% of the time the problem was user error and they could spot that so their unit never was written up to clog up the system by a tech trying to reproduce a problem that was not actually there.
Those inclined to help, please ask for details of reproducing the problem and exactly what is being observed. If they have no test instruments the best for all involved, particularly, the gear owner, is the suggestion to take it to someone who does.
The first steps in diagnosis it finding out if the problem will prevent normal testing, for example blowing fuses, smoke. A lamp limiter can save fuses but it is also going to thoroughly confuse any readings because the mains voltage to the unit will be very low if the bulb is illuminated. A variac with current metering is more useful in troubleshooting but it is rarer than a light bulb.
When asking for measurement readings be specific in what conditions(0 signal/with signal of xx khz and xx millivolts, gain settings etc)
If the goal is a learning experience, when asking the owner to make a measurement, explain why and what they are measuring and why it is important. If you do not know why, maybe it is not a good thing to add confusion by asking for it. It is entirely appropriate to ask for references from manufacturer service notes or a history of a problem being a common problem before accepting the usual, "oh, they always blow up that way, it is xyz part". Unless they are a full time bench tech, saying a problem is common is hearsay. A real tech will have a large body of past repairs to tell them whether it is a common problem. Ask how many of a sample is that conclusion drawn from? If asked why they are saying "xyz always goes out in those" usually means "I saw it once". There are lots of possible causes of similar symptoms. In any given unit, thousands of possible causes for the same general symptom. That is why a good tech will ask for more detail in measurements to isolate the symptom from other similar general symptoms.
Expect when high current stages short out, it is very rare for a lot of things to fail. Replace only those things which can be demonstrated to be defective(there is plenty of time later on after it is working to do "restoration". When a shop replaces a lot of things in a normal repair it is a good indication of internet-shotgunitis or just trying to run up the bill. For example the common "wisdom" or replacing all electrolytic caps as a matter or course is surely someone who wants to make an extra $100 or has been reading too many internet gurus. Any changes or "upgrades" done before the defect is resolved is just confusing the situation and possibly introduces more problems than any that could be helped.
Fix the amp or unit by gathering evidence and coming up with a hypothesis that explains all the symptoms and readings. If it does not explain them all, the hypothesis is wrong. Some of the suggestions well meaning people make are clearly wrong from the existing readings and evidence.
Many of the suggestions are made by putting too much faith in an rare incident in the past. For example the most frequent two suggestions for all manner of defects is to "resolder the board, those have cold solder joints", and "replace all the capacitors". There are cracked solder joints that cause intermittent problems but they are almost always localize to interface components like jacks, pots and stressed joints like large can filter caps supported by solder joints. Everything else, "the cold solder joint" is very rare and seldom the problem.
Out of the last 60,000 repair work orders I doubt there are 10 with defective solder joints that were not obvious by the symptoms or the stress placed on the joint.
Resoldering a dense pc board is a bad idea unless you really know what you are doing. One problem is reflowing old solder that has dull grey surface oxidation just makes the joint worse. Don't reflow any joint, replace a joint completely by removing the old solder and using fresh flux and solder. But better, don't at all unless it is cracked, or the trace pad is cracked. The second reason resoldering a whole board is not good practice is the likelihood of creating a solder bridge.
As a newcomer, don't get too carried away with soldering or worse, de-soldering. Unless you have a lot of experience every time you desolder something the unit has lower long term reliability. PC boards are fragile and unless using good technique removing a part is going to damage it. When clients bring a amp for me to check out before they buy it, I open it and see if it has been worked on. If is has, I tell him it will not be as reliable and has a lower value than if a tech worked on it who was so good that it was not obvious from a glance that it was worked on. Most older amps are not worth as much as the unsuspecting buyer thinks due to hack repair attempts. You should not have to remove any components in troubleshooting so unless it is a large power amp, the repair will probable be 1 part replaced.
Don't confuse trouble shooting and internet guru lectures on Youtube. Most of the gurus are hacks who are more salesmen than tech or engineer. If you are serious about repairing, collect evidence and pinpoint the problem. The problem is never because you do not have $85 hoo-doo capacitor or gold plated transformers.

[km6xz]

Or maybe a large human selfie camera...


What is it with women taking 100 pictures of themselves every day? Since I do photography, girls come to me every place I go and ask for photos or sessions. That is how I met my GF.

I discovered long ago the secret for having pretty girls come up to introduce themselves is to have really cute tiny puppy, or have a long fast camera lens. A walk in the park or club results in several girls coming up to me, even when on a date, asking for photos. We are going to a Belgium pub to watch Liverpool vs Manchester U football( I am not a big football fan but the atmosphere is fun) with another couple. He bought a $5000 camera like mine after a walk in the park where he was amazed at all the attention I got while he, a rich 30 year old private equity trader, good looking fit guy, was ignored.

[Leo_Gnardo]

Or maybe a large human selfie camera...

Yeh, that too

What is it with women taking 100 pictures of themselves every day?

That, and "everybody" taking a photo of their food... what a wacky world. Do they do that in Russia too?

Around here selfies are the thing all right, fit the following to an old Sly Stone song "It's a vanity fair..."

Can't afford a $5000 cam/lens, maybe I'll try fitting my spotting scope to my old Olympus SLR.

Stan you get the prize for fast typing in that last long long post, all good stuff!

[km6xz]

What long post? Sometimes I get carried away typing with 1 finger on my phone....
Yes, the here girls are nuts about photos but they have an excuse most are very attractive fit and stylish.

[Leo_Gnardo]

How things really are at the local. Must be the pocket protector that sets 'em off?

[Enzo]

I mentioned pocket protectors to my sister on the phone not long ago, and she poo-pooed me, claiming they haven't made those since the 1950s. I was at Staples the next day, and I bought her a pack of pocket protectors. I hope she enjoys her Xmas gift.

[km6xz]

I better not show that to my GF, she would make me wear one to ward off the girls wanting photos. We went to the Belgian gastro pub for food drink and game, and then went to a wine bar that is an in-place now for young people getting into wine, trendy hip and cheap. A guy from the Netherlands joined us, and after taking photos of the group, soon a group of 6 young women moved from their table to joined us. They were celebrating a birthday but saw we were having more fun. It was fun, my GF, my trader friend's gf, the 30 yo guy from Amsterdam, a museum architect. Even by accident the 8 girls and 3 guys maintained the proper ratio of men to women for a great time. Some very cute vivacious young ladies at the table which always makes for an enjoyable evening. My gf is a decade older than the next oldest who joined us but she is still 1/2 my age. Naturally all the girls wanted photos and enjoyed posing and vamping for the camera.
The guy from Amsterdam was in heaven, and was giddy with all the cute girls, who were so friendly and outgoing, as his first experience in visiting St Petersburg. That does not happen back home.
When visitors plan on coming and ask for nightlife suggestions I tell men to pay particular attention to their spouse or else there will be hell to pay with a jealous wife who usually mistake the friendliness and beauty of the girls as a serious threat.

[Mark Hammer]

When one reads the research literature on expertise, and what's different in the thinking of experts and novices, one of the things you run into is the expert trait of narrowing down the "search space" by eliminating the irrelevant. Even when experts are making decisions at lightning speed - such as a forward in front of a hockey net determining what to do with the puck right now - they have eliminated, or otherwise carved out, all of that which simply doesn't matter, such thatthey can focus on making decisions about what does matter. That tendency/trait is something that comes with time, experience, and the right kind of practice. It certainly doesn't come from anything "special" about their brains.

So, when diagnosing tech problems, one will often see suggestions that may seem dub, but are really intended to be able to completely cross something off the list of possibilities, and be able to say "It's definitiely not THAT, so I don't have to think about it any more". Other volunteers may be more likely to attempt todiagnose the problem and offer up the first solution, or first approximation of a solution. That first approximation may also be an I-can-cross-that-one-off suggestion, but provide some additional diagnostic information.

In some instances, I don't think it is unreasonable for the sequence of suggestions to be predicated not on highest likelihood, but rather on quickly eliminating the biggest source of nuisance in a repair, biggest cost, or proposing the simplest test for a requester of unspecified expertise.

None of those are "wrong", unless they waste a lot of the person's time, or risk damage or injury. Apart from those caveats, they are just different strategies.

[lowell]

Well said Mark. Repair IS all about narrowing in on the problem. IE, a basic example, is the problem preamp or power amp related. And yes, crossing suspects off the list one by one.

[nickb]

Or maybe a large human selfie camera...


What is it with women taking 100 pictures of themselves every day? Since I do photography, girls come to me every place I go and ask for photos or sessions. That is how I met my GF.

I discovered long ago the secret for having pretty girls come up to introduce themselves is to have really cute tiny puppy, or have a long fast camera lens. A walk in the park or club results in several girls coming up to me, even when on a date, asking for photos. We are going to a Belgium pub to watch Liverpool vs Manchester U football( I am not a big football fan but the atmosphere is fun) with another couple. He bought a $5000 camera like mine after a walk in the park where he was amazed at all the attention I got while he, a rich 30 year old private equity trader, good looking fit guy, was ignored.

You must have a VERY big lens

[Chuck H]

None of those are "wrong", unless they waste a lot of the person's time, or risk damage or injury. Apart from those caveats, they are just different strategies.

So I guess "First, fill your bathtub with water." is out then.?.

[The Dude]

So I guess "First, fill your bathtub with water." is out then.?.

Of course it is. Some folks may prefer Jello.