Caps are cheap, dirt cheap. Maximum $5 each.It would be a shame investing in caps if that is not the problem. I can imagine they would be expensive.
Caps are cheap, dirt cheap. Maximum $5 each.It would be a shame investing in caps if that is not the problem. I can imagine they would be expensive.
Manual says the following:The odd thing here is that more than one voltage is involved, see if they're derived from the same initial supply source or if there's a circuit board somewhere that uses mainly the ones that are affected.
Have not bought the really big ones in a number of years. I just figured they would be expensive. Glad to hear they are not too bad.Caps are cheap, dirt cheap. Maximum $5 each.
If the caps become leaky the voltage might rise. Adjust the pot until the voltage drops a bit, but don't go all the way.Manual says the following:
The +50 volt supply is the reference for all other
supplies and must be repaired first. The +15 volt supply
and the +5 volt supply should be working properly before
repair on the 8 volt supply or the 15 volt supply is
attempted.
So I guess it makes sense that if the +50 is so blasted high the rest of the voltages will be high too.
If the +50 was high would that mean the -8 would be taken toward the positive? It is +1 V.
There is supposed to be a +50 adjustment but I wanted to wait for advice on if it should be adjusted and where it is!
I am guessing that it is not just a simple adjustment. How would it get so far out all of a sudden?
If the caps become leaky the voltage might rise. Adjust the pot until the voltage drops a bit, but don't go all the way.
As far as I know, there is no desoldering involved in removing boards. They are usually connected together and screws attach them to the case, but I could be wrong. The manual will be the best place for information on this.
I adjust the +50 adjust and got it down to +58V before I stopped.If the caps become leaky the voltage might rise. Adjust the pot until the voltage drops a bit, but don't go all the way.
As far as I know, there is no desoldering involved in removing boards. They are usually connected together and screws attach them to the case, but I could be wrong. The manual will be the best place for information on this.
Sorry I guess it is just too late. Time for sleep. Anyway I finally got on the TekScope yahoo forum and someone sent me the manual with the schematic. Thanks for your help.
I might be asking again on another thread. Bu the folks at Tekscopes are very helpful so far and I am on my way to fixing this thing. I think I already figured out one of the issues but I am waiting on a reply on Tekscopes to verify my hunch.
Once I got the schematic I saw that the op amp was in common with both -8 and -15 but I still took a bunch of measurements at the direction of folks here and at yahoo tekscopes.Excellemt! Congratulations!
How did you find it? (And how long did it take?)
Did you adjust all of the power supply voltages?
Do you have any way to verify the calibration, at least for the vertical voltage display accuracy and the basic timing accuracy? You can probably do a "poor man's calibration" of those, even without any specialized equipment.
Speaking for us old guys, when something fails that is that old, there's gotta be a reason.
John
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