Anything to do with Electronics
I am currently working on a Denon AVR-S500BT receiver and can not find a datasheet for the MAIN Transformer part number 943102100350S or transformer model number CLT5U056ZU. I have looked every where but can not find any information on this transformer. If anyone knows where I can get a copy of the datasheet for this please let me know. Or if anyone knows what the code numbers mean. The only other information on this part either on the transformer or in the service manual located on the tag is “RJ 4416 SET”.
OK so no one replied with help on that transformer datasheet but I figured it out myself. So I guess the old saying “if you want something done do it yourself” seems to be correct.
Now for my RANT !
On another note my biggest short comings is in reading schematics, breaking them down and following power and signal paths through individual circuits to locate where the faulty component is without having to test every single component on every board just to find the one component that has failed. I wish someone would make a video in great detail starting with a simple circuit and work all the way up to a complex multi board system with both audio and video components and explain every single step in the simplest way so even a person who never read a schematic could understand. The problem I find with dozens of youtubers trying to do this is that they explain things from their perspective without consideration to the observer who may know nothing. Then most just jump around not having any continuity of information. This is where they all fail using terms and jargon like the observer already knowns them. Every time a term or acronym is introduced it needs to be explained. Everything must be methodical starting at the beginning and working toward the end building on what has already been learned. But no in every single video I have seen on reading and interpreting a schematic to find which component has failed the person who did the video also failed. I may not know electronics like most people and that I have only been working at learning this for just a few years so am still lacking knowledge and skills But what I do know is TEACHING as I have an M.S.T (Masters in Science of Teaching) and have been told by many and all students I have taught that I am one of the best teachers they ever had.
I want to learn Electronics like Mr. Carlson knows electronics but that seems to be taking way too long as the information is not coming fast enough and in a way that is truly effective to learning and understanding. I feel like I am the fifth wheel on a tricycle with no place to go. Further more all this inconsistency, lack of standardization of component specs, diagram information, schematic drawings, lack of keys to inform those who are looking at the schematic what the hell all the acronyms mean, and just a total lack of information do to country origin or manufacturer. It would be nice if there where voltages and amps listed on schematics at ever component, junction, so one can test to see if a particular place is getting what should be there even if those readings are not static at least give the range. But no what I find is that if you are not an electronic engineer that can do the math or have had enough experience to just know you are left guessing. Hey but that seems to be the norm in most technical fields that way they can justify the huge salaries they get.
Life would be so much better if the world just get over the bullshit and started cooperating instead of competing. Electronics and electrical engineering does not have to be so hard. It is made hard. Also I’d like to say it is long over do to do away with the two party system of looking at power convention. Power from Neg to Pos or the old way Pos to Neg. This is obviously one of the most confusing points of electronics. If they just put arrows showing which way the power is going and label the voltages or amps that would greatly simplify following reading a schematic and finding faults. I know some newer schematics do and some even color code which is great but still there is no consistency. With todays computers ALL schematics should have complete labeling, color coding, lists of components with datasheets and a search feature that not only takes you to the part of the schematic that you want to look at but also supplies you with any and all information necessary to test that component or section of the circuit. For example if a multicomponent system has a CD player that is not working such that the spin speed of the drive motor is too slow. You can ask to list all the possibilities that would cause such a condition and the return would be a list of things to test in a specific order to find the problem. Then if one clicks on a particular item or area of the schematic a pop-up would show you the voltage and amp of what should be there under normal conditions. or a menu would pop-up giving you a choice of information one might need. Or maybe such a program already exists and I just don’t know about it and if not then someone needs to write that program. Maybe I should put that in the suggestion box at Microsoft or Apple.
Ok so Rant over and I feel a whole lot better. Any thoughts on this or suggestions on where I can help with reading schematics and learning how to find faulty components would be greatly appreciated.
@john-barron In one of my earlier posts I did mention that if you look on the web for NEETS modules you can get a lot of pdf’s that are loaded with electronics knowledge. They move from beginner to advanced subjects over 24 modules
https://mrcarlsonslab.com/community/power-supplies/general-power-supply-knowledge/
@john-barron That is the world we live in now. I also have a lot of experience in schematics so that is not a problem to me. Circuit design and “what makes the magic happen” gets a little confusing at times for me. A few things to consider: schematics are not common knowledge anymore, even if it can be provided does not mean they will, the number of people knowledgeable and willing to do repairs is nearly none if you think about it. They would rather keep everything secret so if something stops working, you just throw it away and get another one. Some of us don’t accept that and make every attempt to fix the broken. The days of having the ability to repair are gone for most people. Unfortunate and painful but that is what happens when money gets involved, just takes more brain power than when everything came with a service manual. I generally only reply to topics I am knowledgeable about, but glad you got it figured out.
Radios + Tubes + Scopes + Cars= Nothing better!
@john-barron Although i have come quite late to see your post here & by the look you have solved your transformer problem, there is the issue that often such components in any product will have an In-house code number & specifications etc not be a publicly ‘broadcast’ information. Even the service agents for the equipment very unlikely have a datasheet for it & will usually simply install a new one they order in as a spare part (part-code identified in from the Service Manual for the unit under repair).
Here is where Paul’s video on identifying a random transformer’s windings helps (during his recent Powersupply build for the BC-348 Comms set).
I had a home-theater receiver amp on my repair bench recently that had failed it’s power transformer. It was not looking good for the owner & i was quite stunned the transformer had gone out as they are usually quite robust & reliable. The solution was i managed to buy an entire no-go unit the same series model for the owner’s unit from a local Auction Site. I paid very little for it & was able to save sending a not so old piece of equipment off to recycle. i also stripped out some of the major parts of the auction purchase & put the rest into recycle.
@john-barron hello again, i’ve just read your Rant. I’ll explain i’m a 45yr plus electronics tech whose just hit retirement. Most my career i worked in Broadcast for a radio or a TV Station although i had a good decade in the 1980s with Hitachi & their TV cameras business which took me all over the World.
When it comes to being able to understand a schematic diagram for any circuit the reality is that what you are wanting would be next to impossible. Indeed some diagrams are virtually pieces of art with so much information it can spin your head but more often they are lacking. When it comes to what in the industry is known as Domestic Equipment as in say HiFi gear or Flat screen TVs etc doubly so. Here’s where a Google search for the ” Service Manual ” usually wins as you get a free download .pdf for the unit covering instructions on alignment, mechanical disassembly, parts-codes, specs PLUS the schematic & ‘road maps’ of the PCBs. You should see a service manual set for a now obsolete Sony Betacam VTR. Probably 1000pages & you need a big screen & fast computer! Even worse if you want to fix say Macbook Computers!
Of course you will always need a really good level of knowledge in the basics of electronics to understand for example what “Quiescent Current Setup” etc is referring to & why you need to do such a procedure. There is no way around this part of the hobby. Paul’s patreon videos have been showing some great basics with practical little projects you build too to help build that general basic knowledge. Even i have learned stuff after all these years!
Some of the most ridiculous ‘stories’ i have heard are the folks who’ve fixed something & are really happy replacing each & every single part on a circuit board! They say you don’t need any experience or knowledge. The truth is they just got Lucky & spent waaay too much money on spare parts. Then there is the fashion of replacing all the electrolytic capacitors as in virtually firing a cannon at the equipment is supposed to fix the fault!!! Sometimes you get Lucky but the reality is you risk hiding a fault that comes back and destroys that equipment & the new parts!
The next thing is what you have to do if the piece of gear you have & really need going again is completely unsupported… no service manual etc. Here’s where with your electronics knowledge you Back Engineer the layout of that PCB or wiring system so you draw yourself what is effectively a schematic of the circuit & this then enables you to find the fault although this can take a few hours & on some circuits probably won’t be a win because you discover there are customized parts or modules that are unobtainium at the end of the exercise!
Having some good tools, a place to put it all but a workspace to spread out & leave everything there as you work through the project be it a diy build or a repair where it looks terribly untidy to others in the home and some test equipment is a must. DMM, an oscilloscope, a current limit/voltage adjustable bench power, soldering iron (learn how to solder properly) are probably the absolute minimum. And then when fault finding a piece of Mains equipment, having a Dim Bulb setup to limit current if there’s a fault along with a Variac voltage adjusting unit & isolation transformer really is helpful. That depends on what you will repair or what you want to do with your hobby in electronics.
When it comes to working on a piece of faulty equipment your approach needs to be logical or else it won’t go well. You don’t need to go testing each individual part! (In any vintage HiFi amplifier i meet the 1st check i do is whether the output power transistors are okay using the diode junction function on my DMM, a quick & basic emitter base, collector base check test). That said the usual 1st step is visual & often a sniff test to see what might have let the smoke out or exploded… Sometimes the circuit board etc is filthy so this really hinders things. Having a description of events & what went wrong by anyone who saw the thing fail is also very handy! From there it’s power up time but especially if it’s Mains then seriously consider using your Dim-Bulb setup. Nothing worse that blowing the breaker/fuse in your own home! Next it’s measuring voltages & that includes whether the AC volts is making it to the Power Transformer & it has anything AC voltage wise coming out of it. (You need to adjust the thinking processes & approach to accommodate what you are working on). Next it to identify if the DC rails are present from the power supply section… From there if its an amplifier you may need to chase a test signal through the preamp stage to the power output so that will need a schematic and for you to already know input to the base of a transistor, output on the collector or the emitter… similar for vacuum tubes in the grid out the plate (but here be very careful or the high voltage can so easily be a nasty final experience)! Sometimes it might be easier to use a signal tracer to listen to the test tone from your signal generator you connected to an input being passed through. (Paul’s ultra probe non-contact tester is just perfect for that approach).
Another practical approach to working on anything electronic that has failed & you have no schematic etc is identify any of the more physically larger ICs & search their partcode for a datasheet which often results in a schematic diagram not unlike what you are working on!
This waffle has gone on a bit too long. I hope though that some of my ideas & years of experience i have impart just a wee bit of info that will help you in your hobby… 🙂
@peteb2 Well first I am no stranger to schematics as I do have a degree in mechanical engineering from the Navy. I just don’t like how the different companies and manufacturers don’t get together and all standardize how things are done and include all the information. We have a saying in the Navy “There is the right way, the wrong way and then there is the Navy way” which translates to STANDARDIZATION across all things in the military such as electronics or mechanics. This makes things much easier to learn and work on as it does not matter where or what. It all comes down to getting things done in a timely manor as efficiently as possible. However that is not the case when it comes to the civilian world.
Second even though my training was not in electronics I find it fascinating and that is why when I retired several years ago I took up electronics as a hobby. I found Paul’s videos enlightening and it sparked me too dive in head first. In the last three years I started out working on my kitchen table eventually building a lab in my basement with almost all the necessary gear and a parts supply, costing me over $35,000. I started out repairing my own stuff like appliances, speakers, tools and then moved on to making some of Paul’s things like Capacitor tester, trace scope and other things and now am trying to repair old stereos. I purchased several from yard sales cheap like this Pioneer SX-939, SANSUI 3300 and several others. This is where things started braking down when I could not trace through schematics to locate which part has failed. I have just been shot gunning starting with cleaning, then physical inspection looking for anything broken, burned, swollen etc, checking power supply stating at the transformer and trying to work forward. Then doing what Paul said about replacing all of the electrolytic CAPS, testing transistors, resistors etc. for voltage and specs, cleaning all the switches and pots.
I do realize that the Block diagrams help in isolating a particular area and that it is necessary to use that with the over all schematic. But even that is confusing as if the system is complex such as a large tuner with power amp that has multiple connections for many other components it becomes a spiders web from which there is no escape. One of my ideas taken from my experience is that if all manufacturers created separate block diagrams and schematics for each individual section that would make running down faults so much easier. Example: Take a multi unit system like SONY CFDZW755 which has tape, CD and AN-FM radio and the CD section is not working. Instead of a block diagram and schematic for the whole system, if they had separate diagrams and schematics for each section one would find tracing out the fault in any section so much easier then looking at the whole and trying to figure out where it begins and where it ends.
As for Transformers what do you do if you don’t have specs on what the outputs should be on all the taps on the secondary side or for that fact any taps on the primary side as no where have I found in any service manual where that is stated and most schematics don’t list it either? All I found is a part number or some other number that tells you nothing about what the transformer is supposed to be doing. So testing the input and out put will only show you if the transformer is working or not but what if it has some other problem like excessive resistance and is putting out the wrong voltages? How would I know that without a datasheet or proper labeled schematics? I watched Paul’s video on Transformers and that was great as far as figuring out if the transformer is BAD or what the current outputs of all the taps are, but what if the actual voltages coming out are not what was intended because of some internal issue? Am I to assume that if there is a voltage the transformer is working that it is not the problem? When in fact it could be if the voltages coming out are not within spec.
I am beginning to think that electronics has been made way to complicated just because throughout history a few people refused to change things just because of vanity or the sake of MONEY PROFITS and so proprietary engineering became a thing. And if this is the case then the sooner the World Unites under one banner, one law, one rule and cooperates instead of competes the better it will be for all. Whoa did not mean to go off on another rant but that is what happens when I get to thinking about how screwed up things are.
Ok so I guess all I can do is grind away at figuring things out until I fully understand how to work through a system to find where any faulty components are and put things into perspective in a systematic way.
@john-barron My input on the transformer situation. I haven’t found or really heard of cases where a transformer had excessive resistance. It is more of a go/no go part, either there is output or there is nothing. In the cases where the voltage is low, look at the circuitry around it as if it was loading the voltage down. Yes you could have shorted windings that would result in reduced output however there is likely something else that contributed to that. At most the primary windings are 2 connections or more if there is multiple voltage taps. Secondary circuits can vary of course but they should all have something on them in some configuration. No harm in taking a meter and moving around to different taps to map out the windings, unless we are talking about a high voltage circuit care would need to be taken of course. Bottom line is there will be variation to any spec on any circuit, most failures are going to be cut and dry, it works or it doesn’t (transformers).
@peteb2 great points you mentioned
Radios + Tubes + Scopes + Cars= Nothing better!
@john-barron The reality is that what you want is never going to come, especially your united World. I spent my last 29years employed at a TV Station as a studio tech & boy did i see some really neat gear at my repair bench. But as the money began to shrink from the advertising revenues the company made reduced expenses & 1st to go was my ever seeing the sort of Test Gear you needed just to be able to do my work. It became impossible to confirm the now Serial Digital Signal was ‘traveling correctly’ was a no-no so it made for a horrid atmosphere when you’d be asked why & my answer was i cannot confirm so i cannot give you an answer. Then there were the switchmode powersupplies. We needed a specific replacement & our local agent wanted USD$15,000 for it but i found it in the States as a standard spare part for USD$2000. I tried to buy it there & then (stupidly on my own dime just to get the job done & then fight for repayment) but suddenly i found they were not able to sell them as there was an embargo to 3rd party sales & they redirected me to the manufacturer of the gear with their inflated prices for profit we had that needed a new PSU! Talk about corruption & the mighty $.
When it comes to reading any schematic your basic electronics knowledge will let you recognize how the signal is being passed between transistors…. You’ll recognize the likes of a ‘long tailed pair’ or a differential pair etc etc… It should not matter how the symbols are drawn as long as they’re not badly drawn by hand!
One example that i found so good to work on was my Sony multiband receiver, the ICF-6700W. The schematic showed the signal path in red, the transistors mostly tagged with a voltage reading… A joy to use. Compare what info i could findf on my 4 month old Tecsum comms radio PL-880. They refused point blank no information, it is company asset! It had gone deaf on AM suddenly & to return it to Amazon under a warranty claim i’d bought it from was going to be terribly expensive! So i found after some very careful searching the back-engineered notes from a Russian gent! It was his notes that enabled me to locate why the PLL section was no-go.
In the end really, to enjoy this hobby it pays to just do those things you like & enjoy. I know for a fact if i go to do a project that comes from Europe then the logic gates mean nothing to me because they use another set of symbols so i will end up making my own diagram or search one someone has done! There are always ways to, as they say skin a cat.
And finally should you ever have a stumble with anything that is not making sense then feel free to reach out to me & thers here for clarity! I spend an inordinate amount of time infron the computer screens & must have currently 3 chaps in the world that I’m helping fix their old stereos. Cheers!
@peteb2 Well since you offered I do have a question about transistors concerning the collector emitter. I always thought that the power comes in on the collector and goes out on the emitter. OR can it go the other way round: In on the emitter and out on the collector? and if so when and why does that happen?
@john-barron think of the polarity of a standard bipolar transistor, NPN & then the PNP.
On a NPN the Collector is best thought of as needing to be joined effectively to the ‘positive voltage supply’ whereas for a PNP the emitter becomes the ‘negative voltage supply’. That can be confusing. On a schematic traditionally the supply rail Positive is drawn at top of page, the convention just evolved that way while to make sense if using a PNP device i’ll put the negative rail at the top of page & that way the Emitter is symbolically in the correct orientation so to speak… I’ll see if i can find a couple of images to explain this …
Actually my previous post is more confusing than it should be… (joys of being distracted as you type it i guess). What i was trying to say was that in the past …When PNP transistors were the predominant type, circuits were usually drawn with the positive rail running along the bottom of the diagram and the negative supply running along the top. The positive rail was also generally used as the circuit earth rail / input common / output common, so in primarily PNP circuits the transistors were drawn with their emitters descending towards the positive (earth / ground) rail.
@peteb2 I am more confused by this. Are you saying that NPN transistors are for positive voltage and PNP transistors are for negative voltage? But the power flow through both are from collector to emitter? I guess this is a result of my BA in chemistry where I look at things as either negative or positive, Positives are electron accepters which in electronics is called “HOLES” I call Protons and Negatives are ions with extra electrons that donate electrons. So in my way of thinking electron flow is power and electron flows from the negative side of the power supply to the positive side of the power supply. That flow is energy and power is the quantity of electrons that flow. So again in the flow of power is it from collector to emitter or does it differ with NPN vs PNP or is it something else that determines which way power flows through a transistor ? Oh and I know that this is more of a DC circuit and that an AC circuit electrons move back and forth.
Also in chemistry we call positive charged ions Cations and Negatively charged ions Anions and from a chemists point of view as power moves through a wire ie. electrons either DC or AC what is happening is that ions are switching from one state to the other pushed along by voltage from the source.