(Topic ID: 280880)

Squawk & Talk -5vdc low

By TZ

3 years ago



Topic Stats

  • 5 posts
  • 2 Pinsiders participating
  • Latest reply 3 years ago by TZ
  • No one calls this topic a favorite

You

Linked Games

No games have been linked to this topic.

    You're currently viewing posts by Pinsider TZ.
    Click here to go back to viewing the entire thread.

    #1 3 years ago

    My Pac Man sound board has no sound and I ran a check on the test voltage points to discover about 1.5vdc at test point TP4. My guess is the the MC7905 regulator is bad since it has about -14vdc coming in to it. I don't happen to have any and was wondering if their any other components that are an equivalent?

    #3 3 years ago

    Will a 7905CT or L7905CY work?

    #5 3 years ago

    Thanks for the detailed description. I understand the differences you described in the packaging of the unit, definitely need the TO-220. In this application it the negative output voltage that is important. When "googling" these things some say they were positive voltage for the same item numbers, confusing.

    Thanks again for the help.

    You're currently viewing posts by Pinsider TZ.
    Click here to go back to viewing the entire thread.

    Reply

    Wanna join the discussion? Please sign in to reply to this topic.

    Hey there! Welcome to Pinside!

    Donate to Pinside

    Great to see you're enjoying Pinside! Did you know Pinside is able to run without any 3rd-party banners or ads, thanks to the support from our visitors? Please consider a donation to Pinside and get anext to your username to show for it! Or better yet, subscribe to Pinside+!


    This page was printed from https://pinside.com/pinball/forum/topic/squawk-amp-talk-5vdc-low?tu=TZ and we tried optimising it for printing. Some page elements may have been deliberately hidden.

    Scan the QR code on the left to jump to the URL this document was printed from.