hello friends and happy easter,
I have the following problem:
Tektronix Spec: 2755Ap
missing +9V
I have not found application or manual.
There is a rest voltage around +1,2V, so it may be possible anywhere is a LM317 with a bad 240 ohms to ground: the only logical answer to this voltage.
But I don´t want to make shitty work here, this is a wonderful instrument. So please dear insiders, where I have to look for this problem?
It`s a ESD home, so I don`t like unscrew too much parts.
thank you for a tip and greetings from germany
Martin
Check the fuses under the little cover on top of the PSU.
You'll find at least the 494 schematic on KO4BB's website (think of donating once in a while, all the traffic and site maintenance cost him).
On these SA's à lot of tantalum capacitor problems with age.
All of the 275x models are rack-mount versions of one 49x model or another. The 2755AP is a repackaged 492BP if I recall correctly. Basically a 494AP with 100 Hz minimum resolution rather than 10 Hz.
I'd probably use the 494AP manuals from ko4bb.com to troubleshoot it; the 494 manuals may be a little too old.
Check the fuses under the little cover on top of the PSU.
thank you. 2A was blown.
LM317 at front board was defect, also the driver transistor for ON/OFF the light.