Tek 7313

[dom0]

The small mainframes (73xx, 74xx, 75xx, 76xx) usually don't have the lamp power fitted.

If you have checked all connections, power supplies and knobs, then I'd say it's time to get out another scope and check whether the vertical and horizontal signals are correct, working backwards from the deflection plates or bisecting from the main board.

[mike11]

The small mainframes (73xx, 74xx, 75xx, 76xx) usually don't have the lamp power fitted.

If you have checked all connections, power supplies and knobs, then I'd say it's time to get out another scope and check whether the vertical and horizontal signals are correct, working backwards from the deflection plates or bisecting from the main board.

i would appreciate some guidance as to what to check and where ... I have another here to check what ever is needed.....I just checked all my voltages on the Z board again to be sure a few are low but not sure if this is my prob or not

here is what they are at the following plug locations

PLUG 1172

Volts          Measured volts
250           232
130           130
50             50
15             15
-15           -12.2
-75           -69

PLUG P1171

-50         -49.9
pin 7      -12.2
130        130
+50        +49.9
+15       +15
+5          +4.9
-15        -12.2

PLUG P1170

-15        -12.2
5          4.9
15         15
130      129.9
250      231

[tautech]

Table 3-1 on P3-4 of the service manual specifies the correct voltages, ripple and tolerances of PSU voltages.
Get all these to spec first, namely -15 and -75 that by your measurements are out of tolerance.

But, this may not be a PSU issue  , more likely a cap between those rails and GND dragging the rails down.

There is much info regarding finding the problem area, have a good study and work your way through things.
No need to make things hard for yourself, just find what is dragging the PSU down, fit this and then trace the scopes analogue signal path with the schematics and the waveform test points.

Any digital stuff can be left unit later if there is a need to look at it.

Again, break this repair into blocks, fix (get to spec) and move to the next step.

[jmsc_02]

How the post above my, verify caps of the power supply. Recently i've changed C811 (cap of the -15v rail) and all the troubles disappear. If I put my scope on the supply rail, I could see a lot of ripple instead of a plane and constant signal.

[mike11]

My -15 on a scope looks like a saw tooth .... Lots of rip .....

[tautech]

My -15 on a scope looks like a saw tooth .... Lots of rip .....

That's common also WHEN the supply rail is overloaded.(PSU operating beyond design)
Time to start isolating parts of the scope to see where the culprit is....more reading for you to do. 

[mike11]

As much as a pain it was to pop that cap out I did... My capacitance meter won't go that high but a check with a Dvom and it's wide open, won't charge up at all .... I'm gonna get a good one in there and rule that out before going any further and see where I end up

[jmsc_02]

that's fine. It's a little tricky change the PSU caps but nothing impossible.

Good luck!

[mike11]

ok ... making headway.... changed that cap and now voltages are right on the spot

now with beam find on I can see the traces..... they are compressed horizontally.... they do stretch a hair and are fully moveable up and down...seems now I have a prob in the H amp any suggestions ?

[mike11]

bueler ?

[Addicted2AnalogTek]

You really should go thru and read the Tek troubleshooting guide.  It will have the answer to the majority of your questions regarding the repair of your scope.

http://sphere.bc.ca/test/tek-parts/troubleshooting-scopes.pdf

[mike11]

My machine slows down so bad with PDFs it literally takes a few mins for one page to load then when you realize your 20-30 pages away in the book where you need to be wait another 5 mins for the next of you scrolled to to open and see where you are ...... Frustrating like you can't imagine

[miguelvp]

Add more memory it seems you are swapping to the disk all the time.
What CPU/OS/Memory combination?

I mean, if you can't open an 800 page pdf, how good is your system for doing any electronics? without reading details on the datasheets you are kind of flying blind.

[mike11]

i ha a ttl bible here from ti i use for datas.........its vista not sure on mem but adobe slows it to a crawl

[tautech]

i ha a ttl bible here from ti i use for datas.........its vista not sure on mem but adobe slows it to a crawl

Bite the bullet and upgrade it or download that Tek PDF and get somebody to else to print it, it does comp!cement the Tek service manuals.

[Addicted2AnalogTek]

i ha a ttl bible here from ti i use for datas.........its vista not sure on mem but adobe slows it to a crawl

Bite the bullet and upgrade it or download that Tek PDF and get somebody to else to print it, it does comp!cement the Tek service manuals.

That Tek troubleshooting PDF is the single most informative and important tek scope troubleshooting document for a hobbyist or even a fresh technician (besides the scope-specific manual)... you're pretty much going to be clueless without it..    If you have to pay $5 to get it printed out at a copyshop or UPS store, then do it.

[miguelvp]

Or if you want to stick to Vista and not upgrade your memory, lookup ReadyBoost compatible USB thumb drives and google how to use ReadyBoost, this link is for windows 7 but I think it's similar for Vista:

http://windows.microsoft.com/en-us/windows/turn-readyboost-on-off-storage-device#1TC=windows-7

This one covers Vista, 7, 8 and 8.1
https://www.winhelp.us/use-readyboost-in-windows-vista-and-7.html

Edit: More info from Wiki of course
https://en.wikipedia.org/wiki/ReadyBoost

Don't expect this to do miracles, but it might help with opening those pdf files.

[poot36]

If your computer is using the integrated graphics then upgrade to dedicated graphics because most ATI and Nivida cards accelerate Adobe Reader by using the GPU to render the PDF.  There should be a list of compatible cards out there.  You can also try disabling the Areo interface to speedup graphics display and reduce ram usage.  Ready Boost is limited to the speed of the USB port which for 2.0 ports would be around 20Mbits to 30Mbits per second way slower then using the HDD as swap (around 60Mbits/s or more depending on the HDD).  You can also try a third party pdf reader like Foxit or Cute PDF.

[miguelvp]

It's not about the rendering, it's slowing down because it has to swap applications to the swap file on the hard drive which is very slow because it doesn't have enough memory.

[Addicted2AnalogTek]

Any of you guys think that enlarging the virtual memory allocation would help with his RAM issues even slightly?

Also, I have a couple video cards that might suit your system well if you've got integrated video.  One is a GeForce 4 MX440-T8X 64MB AGP W/TV OUT and the other is unlabeled, but if I remember correctly it is out of a Dell Dimension 8250.   If the vid card option suits you, I would give you the MX-440 card free.  The other I think is a 1GB DDR GeForce.