Products > Test Equipment

Tektronix 5A18N help required

(1/1)

Gianni:
Hi,
I am restoring a 5103ND11 with a 5A18N vertical amplifier. Now the device is working. I heard a "stock" and the 200V fuse was blown. After many checks I discovered that the +200 line is overloaded (but no low resistance can be measured on it). In a short: if I cut the +200V trace on the 5A18, the scope is still working, but without the lights on the panel and making the main fuse to blow.

It seems simple to fix ...but the 5A18N should not use the 200V, according the schematic. Maybe mine piece of equipment is older than the schematic. Has someone the schematic with the 200V for the lights, please?

Thanks

Whitefoot:
This may not apply, but I had a Tek 5223 scope blowing fuses on the 200V supply. See diagram. The 2/10A fuse was blowing. C1220 checked OK and didn't show excessive leakage. C1220 was 250uF 150V. I replaced it with a 150uF, 250V cap and it now works fine.

Whitefoot:
I'm trying to figure out how to attach an image.

Gianni:
I am stupid.

1) i sprayed WD40 contact in the DISPLAY switch were there are 200V contacts
2) I switched the thing on without waiting that the WD40 dried
3) it discharged and burned the 200V fuse and then the main fuse
4) I changed the fuse with a 1A fast instead of slow
5) I spent a day in very complex thoughts and tests asking myself why the fuses blew

With the correct 1A SLOW fuse, everything is OK.....

Navigation

[0] Message Index

There was an error while thanking
Thanking...
Go to full version
Powered by SMFPacks Advanced Attachments Uploader Mod