Tektronix 2230 - New to Me - Some questions on optimizing it

[PicknStrum]

Hey all, this is my first post on EEV blog. 

Just received a Tektronix 2230.  Seems to be working as I'd expect (for the most part).  I'm really liking it so far but do have a few questions.  This is my second scope - I don't know much about them but love to tinker with them and use them with my guitar amps / pedals.

1.  One thing I've noticed is that the display comes off a little bit stroby.  It's not super noticeable but a little bit pesky is how I'd describe it.  The reason it caught my eye is my older Leader LBO-520A has a super clean / smooth display.   But with the 2230, it's like you can see the leading edge of the sine wave each time it sweeps instead of it being a very smooth / single contiguous line.  Is that just normal for this type of scope?  This is when it's in its "analog" mode - as soon as it creates a digital image, it's no longer like that. 

2.  While researching the above point, I stumbled onto this thread:  https://www.eevblog.com/forum/repair/dark-spaces-on-the-traces-of-tektronix-2230-oscilloscope/.  The black dots described in that thread are sort of like what I'm experiencing.  I decided to check out the RIFA caps as recommended in that thread since the issue was sort of similar.  From a visual standpoint, the caps look fine.  Should I change them anyway?

3.  Since I'm inside, is there anything else recommended that I should do / check out?  I plan on spraying some air to clean it out and spraying Deoxit on the mechancal pots, etc. 

4. Also related to the above-mentioned thread, tggzzz mentions turning annotations off to help in that specific situation but I'm wondering if that may help me as well.  I have no idea what the annotations are / how to disable them - I assume this is something I should do in the menu?  If anyone can advise me what these are and where to access, that would be great.

Thank you guys and excited to join the forum!  I really love tinkering with scopes and electronics.

Tommy

[bdunham7]

Change your RIFA caps just because, trust us on that.

For your display issues, in the analog/non-store mode try turning the STORAGE/READOUT INTENSITY knob all the way down and then back up again.  You should see the on-screen display is no longer there and the display should be smoother.  The issue is that the scope has to stop writing the waveform and take the time to write the characters, that leaves a bit of deadtime. 

[PicknStrum]

Change your RIFA caps just because, trust us on that.

Sounds great - I pulled them out.  There only seemed to be 2 and the only place I found them is on the board that takes AC directly in for the scope - does that sound accurate?:



I'm guessing I should replace with something other than RIFA caps?  Sounds like these are prone to failure.  Here is what I'm thinking instead:

https://www.mouser.com/ProductDetail/KEMET/PHE850EA4220MA01R17?qs=8JfEd73l2VjkXb2pXLJTgg%3D%3D

For your display issues, in the analog/non-store mode try turning the STORAGE/READOUT INTENSITY knob all the way down and then back up again.  You should see the on-screen display is no longer there and the display should be smoother.  The issue is that the scope has to stop writing the waveform and take the time to write the characters, that leaves a bit of deadtime. 

Thank you for explaining this - it makes perfect sense.  I figured the "annotations" referred to some of the output on the screen but had no idea how to adjust it - I assumed I had to do it in the menu but will try using the readout intensity.

[bdunham7]

Sounds great - I pulled them out.  There only seemed to be 2 and the only place I found them is on the board that takes AC directly in for the scope - does that sound accurate?:

I'm guessing I should replace with something other than RIFA caps?  Sounds like these are prone to failure.  Here is what I'm thinking instead:

https://www.mouser.com/ProductDetail/KEMET/PHE850EA4220MA01R17?qs=8JfEd73l2VjkXb2pXLJTgg%3D%3D

Yes, those are the two.  The replacements you have listed are fine if they physically fit--you want the same lead spacing and no physical interference with other components.  You should be able to find some that are mechanically identical, but they don't really need to be.

[jonpaul]

See W140 and BAMA archive for serv manual and op manual

Go to groups.io tekscopes and tekscopes2 forums many experts and ex TEK guys there.

Jon

[PicknStrum]

See W140 and BAMA archive for serv manual and op manual

Go to groups.io tekscopes and tekscopes2 forums many experts and ex TEK guys there.

Jon

Thanks for the tips!  I'm definitely going to join the tekscopes forum at groups.io.  Also, forgive my ignorance but I'm not sure what W140 and BAMA refer to. 

I was able to find the operator's manual on the Tektronix site and found the service manual on TekWiki but if there are other resources, I'd love to take a look.

[PicknStrum]

Change your RIFA caps just because, trust us on that.

For your display issues, in the analog/non-store mode try turning the STORAGE/READOUT INTENSITY knob all the way down and then back up again.  You should see the on-screen display is no longer there and the display should be smoother.  The issue is that the scope has to stop writing the waveform and take the time to write the characters, that leaves a bit of deadtime.

RIFA's are replaced and you were exactly correct on the readout intensity.  Thanks again!

I do have a follow-up question I'm hoping you can help me out with.  The readout on the left side of the display is a bit cutoff (volts on both top and bottom of the display).  Is there any way to move the readout horizontally?  I've combed the user and service manuals but was unable to find any obvious adjustment for this.  I can post a picture after work if it helps explain. 

[bdunham7]

I do have a follow-up question I'm hoping you can help me out with.  The readout on the left side of the display is a bit cutoff (volts on both top and bottom of the display).  Is there any way to move the readout horizontally?  I've combed the user and service manuals but was unable to find any obvious adjustment for this.  I can post a picture after work if it helps explain.

There is an adjusment specifically for this on p. 5-24 section 14 of the manual, "Adjust Vector Generator", but you might want to do all the other adjustments listed before it as well as some of them will affect this.  Or if you aren't planning an overhaul and complete adjustment at this time, just tweak this one now and then you'll know where it is if it comes up again later.  You should get a screen that looks like this photo, then you adjust the trimmers to align it properly.