Re: Is it at all possible?

From: Mike Stein <>
Date: Sun, 19 Feb 2017 16:50:19 -0500
Message-ID: <BC3CBBE8755148208F11A4288AF38823@310e2>
Re the common mode choke unless you can find its value specified in a Commodore parts list you'd have to test it, but something like that is pretty hard to test; it depends on the material of the toroid, the number of turns, and the wire gauge.

FWIW, looks like about 17-18 turns on the original.

Nevertheless, I'd think that anything with more or less the same number of turns of fairly heavy wire and resistance in the low milliohms would do just fine; e.g. eBay item 231497118977.

Or you could just forget about it and put in a couple of jumper wires...


----- Original Message ----- 
  From: Bo Herrmannsen 
  Sent: Sunday, February 19, 2017 3:19 PM
  Subject: Re: Is it at all possible?

  so did go through BOM again to try and shave of some cost

  still missing:

              Line Filter 

  can the 2 first be programmed in a new chip like some of the others can? sorry for asking so daft but it could then be an option

  it has been said that the line filter is not that critical, but anyone that has some info on it?

  crystal, strange as it might sound i looked for it at RS Components and Mouser but could not find it

  2017-02-19 0:26 GMT+01:00 Mike Stein <>:

    Sounds like it's really well covered ;-)

    FWIW, the three boards I found at a fast look through the pile are also all Rev A.

      ----- Original Message ----- 
      From: Nick Vivid 
      Sent: Saturday, February 18, 2017 5:38 PM
      Subject: Re: Is it at all possible?

      I have 2 326298 rev a boards I don't mind hacking apart and taking pictures of in the name of science. Let me know if you guys need anything. 

      On Feb 18, 2017 3:45 PM, "Bo Herrmannsen" <> wrote:


        that pic helped me solve the dammn RP4 mystery..

        on the schematic R51 should have been labeled RP4... 

        it connects to pin 4 of the expansion port which on the pic goes to Rp4

        2017-02-18 20:39 GMT+01:00 Santo Nucifora <>:

          I added head-on pics of the 326298 Rev A and C boards. Sadly, the back has a metal shield soldered onto both boards that will be difficult to remove and I'd like to keep these as working boards so front pics only.

          On Sat, Feb 18, 2017 at 2:31 PM, Gerrit Heitsch <> wrote:

            On 02/18/2017 08:15 PM, wrote:

                On 2017-02-18, at 09:36, smf <> wrote:

                "The sweet spot is a 250466 board


                The VIC chip on those boards is a R5, which gives the clearest picture. "

            Not quite... You can get a clear picture from a 6569R1, 6569R3 or 6569R4 (that one is rather rare) as well. The problem on the older boards is mostly the modulator. Replace it with a simple video amp and you will have a very good picture. Ok, you lose the RF output, but who is using that anymore?

                It also has the 8 pin video port, not 5 pin like the earlier ones.

              Which is also not fully correct. Should read "like some of the earlier ones". Not all earlier boards had 5-pin A/V socket.

            Even the old KU board already has the 8pin Video out.


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Received on 2017-02-19 22:00:38

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