EEVblog Electronics Community Forum

Products => Test Equipment => Topic started by: mcookieman on November 04, 2012, 11:05:57 am

Title: Kikusui COM7101A
Post by: mcookieman on November 04, 2012, 11:05:57 am
I recently bought a hybrid oscilloscope off ebay, 4 channels at 100MHz with a 50Ms/s digitizer, as some may have seen in the buy/sell forum.
When I got it the cursor/readout display was too far to the right (half of it was not shown) so I opened it to adjust it, following the instructions in kikusui.co.jp/kiku_manuals/C/COM7000A_E2.PDF (http://kikusui.co.jp/kiku_manuals/C/COM7000A_E2.PDF) There were also some other issues (overscan of the trace, underscan when in B timebase) that I couldn't figure out how to adjust so I just left it.
Overall, I'm pretty pleased with it, the only real problem seems to be the scope takes a few minutes for the display to stabilise. (Before that it shows up compressed horizontally and is jittery)
Took some photos while I had it opened.
(http://i.imgur.com/UXkHMh.jpg)
Front panel
(http://i.imgur.com/oKFkSh.jpg)
quite a lot of toshiba chips, CRT is toshiba as well I think.
Does anyone know what the crud near the bottom is?
(http://i.imgur.com/a4oUqh.jpg)
More crud
(http://i.imgur.com/xRlRUh.jpg)
Bottom of the Oscilloscope with most of the adjustment pots and a lot of hybrids.

A few more photos http://imgur.com/a/P7PLN (http://imgur.com/a/P7PLN)
Title: Re: Kikusui COM7101A
Post by: PA0PBZ on November 04, 2012, 03:51:34 pm
Check the caps in the power supply and in the X and Y amplifier.
Title: Re: Kikusui COM7101A
Post by: mcookieman on November 07, 2012, 06:54:56 am
Opened it up again (more photos! http://imgur.com/a/IjHUk (http://imgur.com/a/IjHUk))
I couldn't figure out how to open up the power supply section fully but visually inspecting the capacitors all of them seemed to be fine, no bulging.
I think the squashed display might have something to do with the time base switches as the squashness of the display changes when the switch is rotated (or the x10 mag is pressed)
I've attached a photo of the power supply caps and what the display looks like on startup.