Ratte Auto Switch

I found a rather interesting project a few months ago where they made a monitor switch for the Amiga that could easily switch between Native (Indivision) and other RTG display adapter. The switching itself was done either via software in Amiga OS 3.x or via manual switch.

This was just what I needed and lately I found that a person in amibay.com sold assembled devices for a OK amount of cash. The delivery was swift and fast so I have my own device in mail two weeks maximum after I’ve ordered it.


The items that I ordered:

  • Ratte Auto Monitor Switch, base unit
  • Connector cable for Indivision AGA MK1
  • Connector cable for Phase 5 CyberVision PPC
  • CIA Cable System

Total cost: €54



The installation

The connector layot of the Ratte Auto Monitor switch is as below. It is very important to connect correct graphic signal to correct port or it might be the last time you use your Amiga. The connector to the left when the VGA out is pointed from you is for the Amiga Native signal from Indivision AGA MK1, the other is for the CyberVision PPC.

The smaller 3-Pin connector (Ratte board on the right) is for the CIA adapter that will be fitted over the U300 chip in the Amiga 4000D.




First of all, mount the CIA-socket module on top of the CIA chip (U300). Be careful to put it in the right direction, but the clip can only be put on easliy on one way, the other three take some brute force. Match the beveled corner in the socket to the beveled corner of the CIA chip and you will be safe.




I used double-coated adhesive tape for the cable that goes from my CyberVision PPC to the Ratte Auto Switch. This will hold it in place between the HDD-bay and the daughter card of the Amiga 4000D.




Next step was to connect the cables form the CyberVision PPC and the Indivision AGA MK1. As I mentioned before, the left-most connector is for the Native Amiga Signal via the Indivision AGA MK1 and the right-most is the one for RTG-card.




Final step before actual test… Mounting the Ratte Auto Monitor Switch into the bracket holder. Nothing fancy, just sitting there and does what it is supposed to do 🙂





It just works! It just works perfectly…

This is one of the “Must Have’s” if you have both for example Indivision and a RTG graphic card. The switch between RTG and Native PAL/NTSC is lag free, depending on your monitor of course.

No more swapping between cables or manual monitor switches that needs to be clicked.

I bought my sample via amibay.com via the user Superbonio so if you are interested in buying on yourself I can recommend him.


  1. Kropp says:


    kann man noch welche bekommen??? Ratte Monitor Autoswitch

    1. highpuff says:

      Sorry but I have no Ratte Auto Monitor Switches for sale at the moment.

  2. Corum says:

    which CIA do I have to use in case of an Amiga 4000T ?
    U550 or Z560?

  3. Corum says:

    to which CIA do I have to connect the PLCC connector in case of an A4000T ?
    U550 or U560?

    1. highpuff says:

      On Amiga 4000T, U560 is the CIA to put the adapter on.

  4. Hi,

    I have a question,
    I would like to run my Ratte Switch with DCE Scandoubler (Internal) and Cybervision PPC together,

    Question is,
    Can I take my CVPPC Original Ribbon Cable and DCE SD Original Ribbon Cable?
    Do I need a special cable for DCE SD to Ratte Switch?

    I think I can use CVPPC original cable. Am I right ?

    Thanks in Advance

    1. highpuff says:

      Sorry for a late answer. If I remember correctly, the DCE has a different pinout than CVPCC so if you use that one you might fry your Amiga.

  5. PRS says:

    Would you allow for anyone to be able to make one yourself?

    1. highpuff says:

      Of course 🙂 I am not the creator and all credits to Ratte himself for designing this.

  6. Cyberstormer says:

    Need help,
    somehow my ratte monitor switch cable detached from the CIA adapter,
    see link with picture

    can you tell me how to solder?
    1 to A?
    2 to B?
    3 to C?
    1 to C
    2 to B
    3 to A
    thanks in advance

  7. Marco Seno says:

    Do you have ratte switches for sale?

    1. highpuff says:

      Yes, contact me through Amibay and/or create a Wanted thread there 🙂

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