Heater wires connection on M15MK1

  • Hi Dear Forum Team


    I am slowly proceeding to make sure I do it right


    I am to the point were I have done all PT wires and also the OT


    This is regarding the Heater wires from power transformer to power supply board this is the white and red wire that goes from PT to power supply board.


    As per below snippet those wires are connected to the power supply board on the 2 lugs where resistor R34 and R35 are connected and I did that as shown


    However the connection continuous and goes again from those 2 lugs to the tube socket but unclear to which socket and how is exactly done


    1) first doubt it seems that the hear wire from the power supply board goes from under the board but that means I need to dismount the board to solder it underneath ? If so why was not mentioned earlier on instructions?

    2) The manual says:

    Now do the heater wiring for all five tube sockets (starting with V5, then V4, V3, V2

    and V1, all in parallel), using the red and white twisted wire.


    I do not understand that how is done exactly?


    Can I kindly get some help or some easier explanation?


    If you need a photos of where I am at exactly let me know







  • Hi Davide,

    Again, I can only advise you to read and learn more about tube circuits. The way heaters are connected always follows the same logic or "rules", basically for every project. The pins of the tube sockets that receive the heater voltage vary depending on the type of tube and can easily be found in the respective datasheets of the tube (types). Please read this http://www.valvewizard.co.uk/heater.html for further understanding.


    All the best,

    Max <3

  • Hi Davide,

    Again, I can only advise you to read and learn more about tube circuits. The way heaters are connected always follows the same logic or "rules", basically for every project. The pins of the tube sockets that receive the heater voltage vary depending on the type of tube and can easily be found in the respective datasheets of the tube (types). Please read this http://www.valvewizard.co.uk/heater.html for further understanding.


    All the best,

    Max <3

    So you are saying the principal is the same as per the 18 Watts project daisy chain? I can understand that but still struggle why instructions are not clear, when I am in front to something new like this project, probably because I am a beginner I easily get confuse.


    Everything I ask there is an old back on explaining things except that I need to learn more, but to learn more I need to do things as well.


    I have done it on the 18 Watts because I have visual clear picture on what to do and how and maybe because I have done it already 2 times but this project confuses me is different from the one I have done on the way how things are processed.


    Anyway if you can't help further thanks to at least try to get back to me, will check the link

  • I have done it on the 18 Watts because I have visual clear picture on what to do and how

    And that´s the problem,you build it by Pictures,and not by shematic,you won´t accept that´s no Build by Picture thing,you expect,all must clear by Pictures and step by step instruction,You didn´t try to find things out by yourself and so you didn´t learn anything!


    I don´t know,how often Max, Moonshine link you the Valve wizard Side,where everything is explained,but it was manyyyy Times.


    I could understand.if Questions about things hard to find out by yourself,but Answers to your questions are easy to find out,if you try to search for.

    " Du willst keine sarkastischen Antworten ? :huh: ,dann stell keine blöden Fragen ! :D "

  • Try to understand how tube heater wiring generally works. As soon as you understand how it works, the instructions in the manual become a lot clearer because you actually know what you have to connect to what point and also why. Then the manual becomes more like a supporting picture instead of a step-by-step Ikea-Instruction.

    The way you ask your questions and the details you demand are clear indicators for your lack of understanding - at this point in time.

    You can see every problem you encounter as a possibility to learn. You think the heater wiring is unclear? Perfect topic to so some research on! Topic researched and understood - you can most likely solve the problem yourself or ask the right question to understand the last detail. What is a bridge rectifier? Perfect! Let's do some research on rectification and how these are implemented in tube amps!


    I am talking about my own experience as I have aquired all of my current knowledge just like that. Except I did it before starting a tube project, but you can just adopt this mindset in every step of your current building process. Only then you learn more and get comfortable. Following step-by-step instructions only will take you nowhere and as soon as you start your next project the same problems arise over and over again.


    You can do it, read and ask if something is unclear.


    Cheers,

    Max <3


    PS: Man, I am a slow typer...

  • Yes it makes sense I understand what you mean. It is true on the 18 watts I built with pictures , and comparing with layout too, but probably never understood what it is the logic behind, the reason why I can do the 18 watts because after succeeding the first time, I have the amp still in front of me and copied the second one from the first. I thought I could get away with this project the same way. I will try to follow your advise.

  • Hey Davide,

    If you really want to understand the topic, I can reaaaaallly recommend these two books:

    Blencowe, M: Designing Valve Preamps for Guitar and Bass, Se


    Designing High-Fidelity Valve Preamps


    They are written by the great Merlin Blencowe from www.valvewizard.co.uk and cover basically everything you need. Starting with the absolute basics of current, voltage and tubes they cover everything including rectification, power supply design, heaters, grounding, hum, components, formulas, charts and a lot of practical guidelines and even cool schematics.


    Cheers, Max

  • Thanks so much will get it immediately.

  • I just bought the book on Amazon


    This is the 18 Watts, it is similar in some principal but it is not the same circuit as the Madamp Amp there is a consistent different.


    the layout there is much more clear with many small details, and this is not pictures, but a layout, I have pictures too, and of course visual help may have helped, and probably without understanding the logic behind.


    The problem is that if I can't get some help I have to hold off this Madam project which means I can't play guitar at the rehearsal place and I have to carry my other amps (18 Watts) to that location every time, it seems that I can't complete the kit until I figure all out, I have a friend but can't also ask all the time anything so yes I must wait patiently. I thought , and I was wrong, that you guys could drive me on, but that is too much of asking maybe, I am member of the 18 Watts Forum and there they explain this with examples and they tell you how to do things that way you learn too this is how I learnt on the 18 watts.


    Your ask is different you are pushing to use my brain on my own and also studying, you are asking me to do it myself which is great but requires time, so this way I have to abandon the project because I got all doors closed :(


  • I am trying to squeeze my brain to some logic.


    If the principal is the same as for any other Tube Amp the heater wires are running out from PT to power supply board connection lugs.


    From there underneath the board those two wires will reach out to V5 socket lug 4-5 on that Socket from there 2 more heater (red-white) wire will connect to V4 same again lug 4-5 and then from there to V3 in a daisy chain in parallel until it ends up to V1 that seems the story?


    Those are twisted wires for avoiding hum, this I know already, and they should stay away from other wires for the same reasons, is that correct?

  • Can somebody explain what the letter A in blue stand for or indication of what?


    I just 'd like to tell me what it means please I am studying reading and doing whatever you suggest but I bought this kit and I need to advance and finish it. Next week the progress will be checked by my friend but for now I have done the heater wires.


    Now I am doing the plate voltage from power supply


  • I'd like to help you but I don't have the complete documentation at hand. Maybe MAD can help you?

    I got this is the blue wire underneath that configuration was already done. The doubt was the heater wiring but got that too.


    The problem is that for the first time I’m reading more and more schematics and layout and even if I still have some enormous difficulties I am understanding more and more because you guys are pushing me on using my brain rather than just tell me what to do

  • Hey All,


    As somebody suggested I bought the book and arrived today:



    I have started the heater wires after reading the Valve wizard, I started from the power supply board but is not connected there yet, i mean not soldered, then from the V5 lug 4-5 and from the to V4 lug 4-5 and then to V3 lug 4 and 9. I didn't connect lug 4 and 9 because I didn't finish yet and I need to change orientation of V2 and V1 I just wanted to show you


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