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A Reason for This Group

  1. Ralph Javins
    Good morning;

    Like so many things, there must be a reason for this group's very existence.

    I can offer the following: Now it does seem that we cannot buy anything which does not have some electronic components in it, or even a full blown microprocessor which is monitoring and adjusting the operation of the thing we have purchased. A very prominent example of this is the nature of the automobiles we can buy today. There are so many electronics systems in our cars now that we can safely say that we no longer take our cars to a mechanic for some work to be done. Now we must find an electronics technician with mechanical aptitude to work on our cars.

    This same philosophy also applies to our cameras. Unless we are buying something made in the 1960s or earlier, that camera will have some sort of electronic system in it, from a built-in light meter to systems that take the light that it sees through the lens and chooses the lens opening and the shutter speed that it believes will work with that scene, assuming that it has an 18% average reflectance. Now we can over-ride the control system and at least tell it to shift the exposure up or down two or three stops when we feel that the scene is not a standard 18% reflectance.

    Also with the cameras come the lenses. Even with the lenses we first started to see with Automatic Focusing capability back in the 1980s, it was noticed at that time that those early AF systems were both faster and more accurate than experienced photographers, under most situations. Yes, there were then, and there still are, many circumstances when you will want to go to a manual focusing mode to get the focus on what you want, or even to get the system to focus at all when you have a scene without any reasonable contrast parts where the focusing system can work. But still, most of the time they really do work.

    Then we can look also at our enlarger timers and other systems that make our work with a camera and film much easier than it was back in the 1960s and earlier.

    So, whether we are building something for our photography, or just trying to repair and maintain the systems we have bought, knowing how to work on electrical and electronic systems and how to use a soldering iron to work with "electrical glue," also known as solder, whether it is the older tin-lead (Sn-Pb) solder or one of the newer RoHS (Removal of Hazardous Substances) compliant solders, if we are going to work on them, we need to know how to do that.

    I have been working with tin-lead solder with rosin flux for over 50 years now. The training received in this realm goes up to the NASA Reliable Electrical Connections School at the George C. Marshall Space Flight Center in Huntsville, Alabama. This is something that you can do and do it safely. There are a couple of things to observe, yes, and there is also the precaution that you cannot use a soldering iron that has been used with tin-lead solder on an RoHS solder constructed circuit. If you do and you use the standard RoHS solder with that tin-lead solder contaminated soldering iron tip, the RoHS solder will not flow properly. It will usually ball up and not make the electrical joint you are trying to achieve. The only real cure is to have two completely separate soldering iron systems; one for the older tin-lead solder and circuits, and another one for RoHS compliant solder and RoHS constructed circuits. DO NOT MIX THE TWO. If you do use an RoHS soldering iron on a tin-lead built circuit or mistakenly with tin-lead solder, that soldering iron now has just been converted to use on tin-lead circuitry only. It cannot be cleaned to make it work again with RoHS circuitry and solder. RoHS irons on only RoHS circuits.

    OK. The RoHS topic is still something of controversy, and, yes, it did come out of legislation, and there are some problems with it. These things and the history are something that may be topics of discussion.

    Welcome to a new group that is about something that is affecting us today.

    Enjoy;

    Ralph
    Latte Land, Washington
  2. stormpetrel
    stormpetrel
    Welcome Ralph! Thank you for your input regarding the RoHS. I'm still using SnPb solder and SnPb paste solder however I will soon use RoHS solder paste with all my new SMD projects. There will be less risk of cross contamination this way. RoHS solder iron tip to fix problem on the RoHS SMD boards, contaminated/SnPb tip for all the other jobs (most of my through all components might have their leads SnPb coated).

    Cheers, Dom
  3. nworth
    nworth
    For those of us old enough to remember tubes (and even remember how to design with them), SMDs are almost impossible to see and work with. But that is what we have to work with now. Modern solder pastes no doubt help, but you need a well controlled oven to use them without frying the components. I've seen a couple of articles recently about adapting a toaster oven by replacing the thermostat with either a more accurate one or with a thermistor connected to a microcontroller connected to the heating element to provide a proper and accurate heating profile.
  4. Ralph Javins
    Ralph Javins
    Good morning, NWorth;

    Yes, I also recall that article. A useful tool I have not yet constructed. However, the miniaturization now available to us as a direct result of the techniques developed for our early years of the space program cannot be ignored. Thank you, Jack Kilby. Yes, I also have an industrial strength hair dryer that will dry one strand of hair at a time, just for use on the SMT devices.

    And, there are a few of us still out here who remember what to do with a 6AU6 or a 12AX7 or a 12AU7 or a 6L6GTB or a 6AL5 or a 5U4GB or an 807 or 6146B or 3-500Z. And there is in the radio room something that uses a pair of Eimac 450TL finals in the output stage. B+ for them is +4000 VDC at 1 Ampere. There is still a copy of Terman's RADIO ENGINEERING and the RADIOTRON DESIGNER'S HANDBOOK along with the RC-21 edition of the RCA TUBE MANUAL and other titles on the bookshelf. A few people still believe that real radios glow in the dark, although I also agree that Lloyd and Iris Colvin, Gus Browning, and Danny Weil probably would have given an entire year's salary for one of the modern miniature 100 Watt marvels we have today that would have taken only one trip in the rowboat from the boat to the beach to get the station onto an island. And while I did lose all of my tubes as a side effect of the death of a marriage, I have been able to replace a few of them. Can't find an Amperite 4H4C ballast tube anywhere anymore.

    Still, there are lots of things we can do on a Do It Yourself basis in photography, even today. Solar powered recharging systems for keeping the cameras and other things working when we are away from home or civilization. Lots of things.

    Enjoy;

    Ralph
    Latte Land, Washington
  5. stormpetrel
    stormpetrel
    Welcome aboard Nworth!

    Placing and soldering SMD components could be very easy IF you are properly equipped.
    I bought a stereo binocular like this one for less than $100 on Trademe (our local ebay here). The magnification is only 10x but it is impressive what you can achieve with a good pair of tweezer (I use those ones ).

    I can place components I can hardly see without the binocular!!! However I don't solder SMD if I'm a bit tired and I don't drink coffee before doing this kind of job.
    I found a small glass of wine before starting the job helps a lot!

    There are different scales of SMD components, and you can use large SMD which are just slightly smaller than their leaded counterpart making the job easier.
  6. micwag2
    micwag2
    Just joined the group. I do soldering, assembling, and testing of gradient amplifiers and motor drives, among other things, for a living. The soldering i do is primarily hand soldering assembly of PCB's. So whether its SMD or through hole I can share what i know about the processes and equipment needed to repair your cameras or build fun projects. I also collect and refurbish all my own cameras and once in awhile someone elses.
  7. BentleyR
    BentleyR
    Also a new group member. An excellent idea, so many of the devices we use today depend on electronics having a place to share knowledge and experiences will be wonderful. I am heartened by your references to 6AU6's and such, you know your screen grid from a ...
    I am in the process of getting a Fairchild panoramic aerial camera up and running and it mainly has been an electronics adventure. It is late '60's electronics (no tubes but discrete transistors) but an interesting adventure. I don't know if it fully fits with your vision for this group but I can offer my very successful conversion of a cheap inverter from 60Hz to 400Hz to supply 115VAC to random aerial cameras or other aircraft components.
    Good luck with this noble endeavor

    Allan
  8. DWThomas
    DWThomas
    Hi all!

    I must admit my DIY electronic tinkering has slowed a good bit, but like several others, my experience goes back to the smell of rosin while soldering. As a teenager in the fifties I worked up to being trusted to troubleshoot the family TV full of those glowing glass things. Today the basement workshop has become so cluttered with 'stuff' She Who Must Be Obeyed wanted out of other places that it's not much of a work space, but somewhere in there is a Hameg dual trace scope, a digital multi-meter, lots of miscellaneous components, and yes, things that get hot and melt solder. I'm not sure how active I'll be in this group, but who knows, occasionally I might have an idea or an answer for somebody.

    I started professionally with electro-mechanical sensors, mostly accelerometers, worked my way up in frequency to some cable TV gear in the 1960s, along with broadband amplifiers for the burgeoning military-industrial complex, later got entangled with some microwave sources, mostly the control/power supply part. Then in the late 1970s came a major segue into microprocessors and software, and embedded systems programming. I've been retired (or at least tired!) since 2002 after an acquisition and downsizing. After being away from some of that stuff for over a decade I sure hope nobody wants me back to work on it.

    If naught else, I want to encourage folks to make things -- the current toss-it-away-and-buy-another lifestyle is (or should be) an embarrassment!

    DaveT
  9. Jim Jones
    Jim Jones
    I tried crystal receivers in the 1940s, and when electricity came to the farm, graduated to VTs. After a Navy career in electronics (including VT computers!) electronics became an occasional hobby. There's still an accumulation of VT tvs stored in the barn with IBM 286 computers and a dual beam Techtronics. The main stash of VTs, two O-scopes, a Hammerlund Super Pro, and test gear burned in a darkroom fire. Oh well, time to move on to solid state.
  10. Steve Smith
    Steve Smith
    "For those of us old enough to remember tubes (and even remember how to design with them)"

    I design and build audio recording equipment with them (although I call them valves).


    Steve.
  11. Ralph Javins
    Ralph Javins
    This is a note prompted by the comment from Dave Thomas:

    Just a few months ago, one of the Subaru station wagons (estate wagon?) needed a new alternator. The original one was then 11 years old. I visited one of our local automobile parts suppliers (stockists), and he did indeed have one in stock for me. Getting the new serpentine belt to drive it was another issue. Anyway, he handed the box to me, and when I got it home, I also read the little fine print on the adhesive label affixed to the side of the box, and it was then that I learned that this particular alternator had been "Remanufactured in China." Wow! While I have become accustomed to the "Made in China" labels on everything now, although I still grumble, I was not ready for that revelation. Now we are not even repairing things here.

    Enjoy;

    Ralph
    Latte Land, Washington
  12. cmacd123
    cmacd123
    I will say my combination of Photography and electronics has mostly to do with my 16mm projectors. Being mostly too shy to try and solder inside a camera. A 6V6 does use a lot of power, but at least you can find it without glasses.

    I assume that if one blindly ignores or is not aware that a given device was built with RoHS standards and plays with it using the ways of our youth, that old fashoned solder will win out over the funny silver-copper stuff that is already there, and so the device will live on (and the circuit board police will come to get you)
  13. Ralph Javins
    Ralph Javins
    The comment by cmad123 is a valid point:

    How do you identify an RoHS system with its peculiar requirements from the older Sn-Pb solder built systems? Sometimes there is a label on the PCB or other substrate with the printing "RoHS Compliant" or some similar commentary. There are also some subtle visual differences in the appearance of the two. After a while, you can start to recognize them. I am not yet sure how to describe the differences.

    Again, this is another example of design by legislation. They want to remove the "hazardous substances," but they did not foresee the resulting difficulties, nor indicate how to comply with their rulings and laws. All they really said is; "You cannot do that anymore." And there is still the point that the RoHS solders require a higher temperature to do their job, so the likelihood of burning the board or lifting the trace is higher. As Otto von Bismarck observed; "There are two things that you should never watch being made--sausage and legislation."

    Enjoy; Ralph, Latte Land, Washington
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