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Products => Test Equipment => Topic started by: Roy Batty on January 03, 2017, 12:21:36 am

Title: Questions About Ancient HP 3300A Function Generator
Post by: Roy Batty on January 03, 2017, 12:21:36 am

So long, and thanks for all the fish.

Title: Re: Questions About Ancient HP 3300A Function Generator
Post by: Andy Watson on January 03, 2017, 01:20:56 am

Doh! Managed to delete rather than edit my post!

The schematic shows a fuse and a power switch in one line. The other line leads to the transformer and the voltage selector switch. I would connect the Hot to the fuse/power switch line. It should be easy to trace the appropriate wire back to the fuse holder.

Title: Re: Questions About Ancient HP 3300A Function Generator
Post by: tautech on January 03, 2017, 05:44:55 pm

Google "dim bulb tester" and knock one together.  ;)

You'll recover the small time and cost to make one in money saved from saving fuses.

Title: Re: Questions About Ancient HP 3300A Function Generator
Post by: tautech on January 03, 2017, 06:09:13 pm

Quote from: Roy Batty on January 03, 2017, 06:02:59 pm

I have one sitting here, plus a Variac. Thanks for the suggestion. I didn't expect it to have this particular kind of problem............

It's wise to place at least a dim bulb tester in the mains supply of ANY equipment that's been unused for some time and if all seems well then a Variac turned down some to let the E caps reform to their correct values.

Title: Re: Questions About Ancient HP 3300A Function Generator
Post by: SeanB on January 03, 2017, 08:11:40 pm

My bet is C7 or C8  on the mains input side have crazed and gone short circuit. Those Rifa clear case capacitors strike again.

Title: Re: Questions About Ancient HP 3300A Function Generator
Post by: tautech on January 04, 2017, 01:02:51 am

Quote from: Roy Batty on January 04, 2017, 12:36:47 am

I assume it must be filtering crap out.

Exactly. Values are not critical.