PatrickMc Posted November 18, 2021 Share Posted November 18, 2021 Hi, First time poster with my first system that is in a bit of rough shape. Machine was pretty much DOA on arrival but when I opened it up it was clear why…. The crystal for the CPU clock circuit was loose and floating around inside the case. Unfortunately, it broke off right at the base and there is no way I can see to solder it back in place. This is the 48MHz version of the board but I can’t find an exact replacement for the original part. Given this is my first TI-99/4A, how precise do I need to match the original specs? Any pointers to suitable replacements would be much appreciated. Thanks! Quote Link to comment Share on other sites More sharing options...
Stuart Posted November 18, 2021 Share Posted November 18, 2021 If you find a crystal of the same frequency and case size then it will probably be ok. You'll probably find loads with a smaller case size, but find the same case size. 1 Quote Link to comment Share on other sites More sharing options...
Tursi Posted November 18, 2021 Share Posted November 18, 2021 The spec for the clock generator is +/-5%, it should be pretty generous in terms of tolerance. Here's the datasheet for it: TIM9904 (clock).pdf 2 Quote Link to comment Share on other sites More sharing options...
Stuart Posted November 18, 2021 Share Posted November 18, 2021 www.mouser.com/c/?q=520-HCA4800-20 Quote Link to comment Share on other sites More sharing options...
PatrickMc Posted November 19, 2021 Author Share Posted November 19, 2021 Thanks to all! The help is much appreciated! ? Quote Link to comment Share on other sites More sharing options...
Like us on Facebook
Follow us on Twitter
AtariAge on Instagram
Watch us on YouTube
Chat on Discord
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.