Re: Is it at all possible?

From: Mike Stein <mhs.stein_at_gmail.com>
Date: Tue, 14 Feb 2017 15:37:26 -0500
Message-ID: <7733043DF424419E8B38CF570472E081@310e2>
I've lost track; which board are we talking about?

m
  ----- Original Message ----- 
  From: Bo Herrmannsen 
  To: cbm-hackers@musoftware.de 
  Sent: Tuesday, February 14, 2017 3:34 PM
  Subject: Re: Is it at all possible?


  double checking stuff and for the resistors i found these odd's:


  Ruud's schematic lists R5 as 1.5 Kohm but the BOM in the service manual says 560 ohm
  R8  is a 1Kohm but BOM says 390 Ohm
  R10 is a 100 ohm but on BOM its a 120 ohm
  R31 is a 1Kohm but BOM says 180 ohm
  R37 is a 47Kohm but on BOM its 2,7Kohm


  R46 is on BOM but not on Ruud's schematic
  The following is on Ruud's schematic but not on BOM: R42, R36, R50, R48, R49


  will go on and recheck capacitors


  2017-02-14 20:58 GMT+01:00 Bo Herrmannsen <bo.herrmannsen@gmail.com>:

      a.. there are a few BOM's in the service manual at zimmers, i used the first one but maybe that is not the right one?
    I can answer this one myself... the schematic has only the 5 pin video so its the first one board in the service manual. PCB 326298-01 Schematic 326106


    2017-02-14 20:35 GMT+01:00 Bo Herrmannsen <bo.herrmannsen@gmail.com>:

      a bit back to the org subject


      BOM: https://docs.google.com/spreadsheets/d/1Gl0Q71u6fKLPRA9HQiSG8-xY8tPweMwXuy_UGQ1Iayo/edit?usp=sharing

      Schematic: http://www.baltissen.org/images/c64.png


      Best photo of a board so far: http://myoldcomputer.nl/wp-content/uploads/2015/11/board-326298.jpg


      I have got most of the discrete stuff sourced, thou i have a few capcacitors i could not figure


      Q's: 


        a.. is mica and ceramic the same thing? i ask because i could not find a few of the ceramics but could find them as mica's

        b.. C106 is not on the BOM on page 22 in this PDF: http://www.zimmers.net/anonftp/pub/cbm/schematics/computers/c64/servicemanuals/C64_Service_Manual_314001-02_(1985_Feb)%20.pdf
          a.. but on the scematic on page 26 it is marked as 150pf but with a dashed box arround it. I looked at the board i just linked and could not find it anywhere. But can i assume that its just a ceramic?
        c.. The socket for the expansion port is also a no go so far, anyone know a shop that has them regular?
        d.. L4 is listed as a line filter of some sorts, but could not find any more info so far, anyone knows more about it?
        e.. RP4 anyone know what kind it is? BOM at the zimmers link says 10 pin so can it be assumed that its 5 individual resistors? 
      Things noted on the schematic from Ruud


        a.. Only one of the resistors in RP4 is connected on both sides, do i miss something here?
        b.. Same for RP3
        c.. there are a few BOM's in the service manual at zimmers, i used the first one but maybe that is not the right one?


      Will do the chips tomorrow, rest of evening will be spent double checking and look a bit more in the service manual




      2017-02-14 8:29 GMT+01:00 Julian Perry <jp@digitaltapestries.com>:

        Hello GJPAA,

        Tuesday, February 14, 2017, 6:01:26 PM, you wrote:

        > Hallo Bo,


        >> First of all i wonder what board rev matches this schematic?

        > I have no idea. The source is the schematic in the well known Programmers Reference Guide.

        As Hans has mentioned,  it looks very, very close to Rev 250407. Nothing was ever absolute with Commodore boards, but I think that's as close as you'll get. Commodore were always tinkering with the analog video and audio (particularly early on) so there may be some differences there. 


        >> and if there are a high res scan "out there" i could use for initial component placement

        > Write me in private and I will generate a PNG with an higher
        > resolution. Or you can have the original files. Eagle can be
        > downloaded and you can create your PNG. And you can tinker with the SCH yourself.


        >> Next would part are ABSOLUTE not to be found no where? 

        > These parts aren't that rare. Just ask around.


        >> and board layout

        > Hasn't that be done already? Several people have asked for the SCH before.

        There was the C64 reloaded a short while back ( http://wiki.icomp.de/wiki/C64_reloaded ). Aside from cleaner video output I didn't quite see the point: but it's always nice to see the C64 candle burning bright !!


        > Hmmm, next thought: what about using the ATX format? 


        >> Next, how much use would the work be in general?

        > Depends on your skills and experience.


        > Met vriendelijke groet / With kind regards,
        > Ruud Baltissen

        > www.Baltissen.org

        Message was sent through the cbm-hackers mailing list 








       Message was sent through the cbm-hackers mailing list
Received on 2017-02-14 21:00:38

Archive generated by hypermail 2.2.0.