UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - Retired Texas TI99/4A engineer needs help please.

Boater Sam · 8th Nov 2018, 3:30 pm

Thanks to Ron (ronbryan) I now have 2 fresh 723 regulator chips. Very generously donated.
So I thought I would 'scope the oscillator chip first.
Cleared some space on a very cluttered bench for the scope and set everything up.
Bah! The Telequipment 'scope has gone up in smoke! The other one is buried under lots of radios that I have put away.

So I'm discouraged and getting pressed for time now, pretty sure that the oscillator chip, TL331 is not working either. Briefly fitting a 723 did nothing.

Got to pack up and mothball the workshop in preparation for going away for winter. Its going to have to wait till late March when I get back.
Thanks to all for the assistance. Watch this space next year!

8th Nov 2018, 3:30 pm	#29
Boater Sam Banned Join Date: Dec 2013 Location: Middlewich, Cheshire, UK. & Winter in the Philippines. Posts: 3,897	Re: Retired Texas TI99/4A engineer needs help please. Thanks to Ron (ronbryan) I now have 2 fresh 723 regulator chips. Very generously donated. So I thought I would 'scope the oscillator chip first. Cleared some space on a very cluttered bench for the scope and set everything up. Bah! The Telequipment 'scope has gone up in smoke! The other one is buried under lots of radios that I have put away. So I'm discouraged and getting pressed for time now, pretty sure that the oscillator chip, TL331 is not working either. Briefly fitting a 723 did nothing. Got to pack up and mothball the workshop in preparation for going away for winter. Its going to have to wait till late March when I get back. Thanks to all for the assistance. Watch this space next year! Last edited by Boater Sam; 8th Nov 2018 at 3:32 pm. Reason: Added