Any build experts willing to help out a newbie?

Discussion in 'The Workbench' started by ledvedder, Nov 23, 2020.

  1. ledvedder

    ledvedder Active Member

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    Hi guys, I really want to build this amp! To me, this is exactly the tone I'd love. But, the only thing that I have available is the youtube clip and the schematic. I'm not even sure where to start. I suppose I'd need to source the parts, since the kit he built upon is only available from Germany. Just wondering if anyone would be willing to help me out?

     

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  2. South Park

    South Park Well-Known Member

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    You need some back ground in electronics to do this stuff . If you study this stuff and understand a lot of it we can help you build this .
     
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  3. thetragichero

    thetragichero Well-Known Member

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    basic soldering skills along with the ability to follow directions and most importantly be able to troubleshoot because the dang thing ain't gonna work first time you fire it up
    lots of reading
    start with a simple fuzz face kit, then maybe an overdrive. then a simple amp kit (I'd suggest a champ)
    then *possibly* from a schematic

    gotta put some work in. this isn't the type of gatekeeping you may get from the grouchy old greybeard tech; this is building block stuff that without it you'll get frustrated and quit at best and potentially kill yourself at worst
     
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  4. StingRay85

    StingRay85 Well-Known Member

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    Its not rocket science though. What is your educational background @ledvedder?
     
  5. anitoli

    anitoli Well-Known Member Gold Supporting Member

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  6. AML

    AML Member

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    That's a fairly gainy version of the classic 18W amp, and while it wouldn't be impossible for a newbie to build, there's a high chance of some SNAFUs and troubleshooting. If he's only sharing the schematic - and no diagrams or photos of how he has done the extra mods - you would have to use the documentation for the original amp kit and then find your own way... and that's a tough thing to do as your first project.
     
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  7. 2L man

    2L man Member

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    If you order from Europe check also Tube-Town! They have many different ($312...$348) 18W komponent kits. Excellent lazer cut chassis are about $35 and face plates about $40. Knobs are also required. I don't know what exact German tax is but it gets deducted when shipped outside EU but if it is 20% it might cover the shipping? Most of their power transformers are europeam 230VAC but they sell also Hammond which many also have 120VAC and possibly they can select that to the kit? Tube Town forum has also English section and for me forum SW translates German to Finnish automaticly so possibly it does English as well?

    Esa
     
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  8. pedecamp

    pedecamp Well-Known Member

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    Do you really want to build this amp or do really just want this amp? 2 different things.....

    If its the build experience go for it, if you have problems you can always take it to your local tech to troubleshoot and get it going. If you just want the amp, I'd send that video and schematic to Nik at Ceriatone and tell him what you want and he will build it for you for about $1K, he probably has something exact to this in his stable of amps ready to go. :yesway:
     
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  9. Gunner64

    Gunner64 Emotional Support Animal Gold Supporting Member

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    Just be meticulous in your work. Double, triple check everything. Look at other builds as to wire dress, routing..ect. If you can solder, use a multimeter, and have the ability to sort parts and label them you should be able to tackle it.

    I sort, and label with masking tape everything before I start anything..then all the same value resistors ect are all strapped in the same label. Makes it much easier than sorting as you go...and if you're short something you know straight away.
     
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  10. jchrisf

    jchrisf Well-Known Member

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  11. ledvedder

    ledvedder Active Member

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    Here is the original amp, https://www.tube-town.net/cms/?DIY/Amps/TT_PX18_(engl)

    The original schematic and layout are on that page, but too large to upload here.

    I'm a fairly technical guy. I've worked in the IT industry for 20 years. I've built computers from scratch. I've also built a few pedals, modded a few amps, and done tons of work on guitars.
     
  12. Gunner64

    Gunner64 Emotional Support Animal Gold Supporting Member

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    You should be fine then.
     
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  13. ledvedder

    ledvedder Active Member

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    Is anyone familiar with the Friedman Smallbox layout? I'm hearing that this amp is essentially an 18 watt version of the Smallbox. Is this correct?
     
  14. Gene Ballzz

    Gene Ballzz Well-Known Member

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    There are some unusual thing going on in the early preamp section, especially with no switching shown. Take a look between V1A & V1B.
    Just My $.02,
    Gene
     
  15. What?

    What? Well-Known Member

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    Looks like a high pass to me, but I don't know what is up with that pot. It is labeled R45/1 and as being stereo. Looks like the other side of it might be at V3A's cathode, although the label doesn't seem to reflect that.
     
  16. Gene Ballzz

    Gene Ballzz Well-Known Member

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    And thus the comment about it being "unusual!" I'm suspecting an attempt at a "one size fits all" setup, to allow some version of cascaded operation (ala 2203), a 2203 style Low input combined with a pseudo 4-hole approach. From looking at it and thinking about it, I'm betting that part of the circuit ends up not really working all that well?
    Just Thinkin'
    Gene
     
  17. jchrisf

    jchrisf Well-Known Member

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    Phillipp has done the same kinda tone with Jet City amps.. maybe get one and mod it?
     
  18. _Steve

    _Steve Active Member

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    The best path IMHO would be to buy an 18 watt kit here in the US so that you get good english step-by-step instructions and support. Once you have finished it you will have just about the knowledge and experience to mod it to the spec you want. Its only a few dollars worth of different components. FYI the schematic you posted is not ideal and could be clearer.

    I built my first amp from a Mojotone kit. The instructions were excellent. YMMV.
     
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  19. jchrisf

    jchrisf Well-Known Member

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    When I was thinking about building one of these because of the video the OP posted.. this is the kit that was at the top of my radar. Comes from England but very affordable even with shipping. He has different options to install if I remember correctly and has great instructions to follow.
    https://www.ampmaker.com/shop/p1800-18w-vintage-plexi-amplifier/
     
  20. Guitar-Rocker

    Guitar-Rocker Well-Known Member

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    There are several stumbling blocks if using that schematic. There is no power section, filtering, B+ shown, so you would have zero idea of the voltages. Granted you could start somewhere and adjust. But for a first timer that is more than challenging.

    Also on the OP's listed schematic, the J2 or J4 inputs may very well be anemic, as the signal from the guitar through the pot will be diminished greatly. Maybe it is not drawn as built. And the px-18 schematic is not close to the Tube Town px-18, although the Tube town shows the missing power section and filtering / voltages

    Note that upon a second glance at the two schematics the original is missing a triode stage from J2 and J4 as compared to the TT schematic.
     
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