1. Things you need to know about the new ‘Conversations’ PM system:

    a) DO NOT REPLY TO THE NOTIFICATION EMAIL! I get them, not the intended recipient. I get a lot of them and I do not want them! It is just a notification, log into the site and reply from there.

    b) To delete old conversations use the ‘Leave conversation’ option. This is just delete by another name.
    Dismiss Notice

ALWSR Online Manual [Alpha Release]

Discussion in 'd.i.y.' started by Andrew L Weekes, Mar 24, 2019.

  1. Andrew L Weekes

    Andrew L Weekes Senior Reverse Engineer

    So this doesn't get lost in the group buy thread, I thought I'd start a new post.

    I spent some time today creating an online version of the ALWSR manual, which I'm happy to receive comments, criticisms or ideas on. It's not publicly linked anywhere yet, but you can browse it here:


    At the moment it's primarily a conversion of the PDF document into a responsive HTML format that works on all devices and scales accordingly, I've added a bit more info on the basics for beginners and we need to review the component list given the obsolescence of Rubycon ZA series caps.

    I don't intend to do major changes, but it would be good to correct any errors anyone spots and produce a live document that can be more easily brought up to date and be readily available online.

    Hope it's useful, pop your feedback below, and we'll talk!

  2. Andrew L Weekes

    Andrew L Weekes Senior Reverse Engineer

    One of the things I don't like is the very poor quality of the original PCB overlay images. I'm thinking we could crowd source some photos during the builds to add to the site, if anyone is prepared to take some decent pics?
  3. timH

    timH Senior Moment Member

    Great idea. I’ve started looking at the BOM. I’ve also knocked up a google sheets file that will take your chosen output voltage and give you a calculated value for R9. You then put in the actual value you’ve chosen for R9 and it gives you a target value for R8. You then put in your actual value for R8 and it gives you Vout and checks how close you are to 500. (Easier to use than to describe)
    If anyone’s interested I’m happy to make it available
  4. Andrew L Weekes

    Andrew L Weekes Senior Reverse Engineer

    I thought about doing the same today - if you want to make it public, I can hyperlink to it from the manual!
  5. timH

    timH Senior Moment Member

  6. 337alant

    337alant Negatively Biased

    Excellent Andrew thanks

  7. geoturbo

    geoturbo Well-Known Member

    Thank you, Andrew, for making all this available.
    Will dig soon in the part list too..

    @timH, guessing column D "R8 calc" is not really needed?
    Btw not sure if your calculator is supposed to work online..
    as I was not able to make it work online, just copied the math formulas and works locally..
    oops.. maybe I should've asked you first.. :)
  8. timH

    timH Senior Moment Member

    No column d not needed really. I could tidy that up
    Yes it’s probably possible to create this as a web form. I’ll look into it but if someone else knows how I’d appreciate the advice
    No need to ask me to use it :)
  9. Andrew L Weekes

    Andrew L Weekes Senior Reverse Engineer

    If anyone can do this with a bit of code I can paste it on the page, never looked at doing this stuff before, would be a cool feature though!

    Sorry been a bit quiet, been utterly wiped out for several days with a viral thing that left me lifeless!
  10. Andrew L Weekes

    Andrew L Weekes Senior Reverse Engineer

    Dowser and orangeart like this.
  11. timH

    timH Senior Moment Member

    Hi. I’ve updated my calculator to do Vout and impedance check .
    Here’s a link

    Andy - I can send you an embed code if you want to insert it into the manual
  12. Andrew L Weekes

    Andrew L Weekes Senior Reverse Engineer

    Tim, that's grand, yes please!
  13. chrisn

    chrisn pfm Member

    Dear Andy
    Thanks for the "online manual". It has been updated brilliantly since I last looked so I think even I can follow it!
    I have x4 +ve and x2 -ve. So I might as well get components for all six. As usual it gets quickly grandiose.
    The plan is to supply Naim preamps, maybe a Prefix and Exposure preamps. Although not all at the same time.
    To start I will just do a +24 (or so) dual rail like a Hicap.
    Can I just drop x2 of the ALWSRs into a Hicap, replacing the original regulator?
    Capacitor banks seem to work well with TPRs, same with ALWSRs?
    How many ALWSRs can you run off a single cap bank / pair?
    Centre tap 125Va 28-0-28 transformer?
  14. timH

    timH Senior Moment Member

    Q3 I’m using 3 x +3.3 v, 1 x +15v and 1 x -15v from one supply to feed my Dac board plus a PFM flea all running from one transformer and one cap bank
  15. IDM

    IDM pfm Member

    Hi Andy,

    I was looking at the wiring connections schemes on the website and if you are wiring a negative regulator the I think TRIN and Tgrnd are the opposite way round to that shown which is a positive reg. If I am right it might be worth putting a note for the unwary.

  16. timH

    timH Senior Moment Member

    I posted this in the ALWSR Build Thread
  17. chrisn

    chrisn pfm Member

    I need some help here. I have done the smd practice kit off ebay (well half of it anyway) and I am ready to start building some ALWSRs for Naim and Exposure preamps. I have read all the available manuals and BOMs and I wonder if I could ask some advice:-
    1. The input voltage max is 35-36v so that limits my tranformer choice to 25v maximum. Can I increase this by using hight rated capacitors?
    2. Which of the two TO-22 devices need the most heatsinking?
    3. I need C1-4 and C8 for each board. C4 seems the most important for performance. The various BOMs, old, new and Italian vary significantly. Can I use any of these which I have in stock from a preamp that did not happen?

    OSCON 25v 10uf and 56uf
    NICHION LF 25v 47uf AlPoly esr 0.03
    ELNA SILMIC II 50v 47uf
    VISHAY 160 RLA 25v 100uf
    PANASONIC AK 35v 37uf
    PANASONIC FC 100v 100uf

    Any help would be appreciated
  18. timH

    timH Senior Moment Member

    The Naim preamps require a 24v supply so the 25v transformer would be fine for them. Not sure what the Exposure runs on.
    I haven’t needed to be overly concerned with heatsinking on the regs I’ve built.
    C4 is shown as 47uF on the original manual but I’ve used Oscons (100uF 16v Oscon SEPC - RS 788-6977Z) so hopefully some of those you already have will be ok - somebody with more knowledge than me will probably be along soon to confirm

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice