You can also post a problem description in sci.electronics.repair, at groups.google.com, especially if Jim Yanik is still there.
One of the first things to verify, after a thorough visual inspection reveals no burned components or other obvious problems, is that all of the power rail voltages are within tolerance. If you have the complete Tek 475A service manual, everything is in there, including a step-by-step troubleshooting procedure. It would be wise to first read the section about how the power supply circuit works.
One of the first things to verify, after a thorough visual inspection reveals no burned components or other obvious problems, is that all of the power rail voltages are within tolerance. If you have the complete Tek 475A service manual, everything is in there, including a step-by-step troubleshooting procedure. It would be wise to first read the section about how the power supply circuit works.
Ok thanks the 5 ohm reading on the power cord wires was with scope off when I disconnected the power supply wires from the transformer it was the secondary wires that come out I the regulated ones after that my ohms were at ol and I got power fan was not on but I had power the tek manual did not say to disconnect them it was a general manual I found online I have checked the three fuses that I could find the inline the one below the inline and the one for the crt on the power board they r all good 0 in diode check the scope has the multimeter on top as well the manual says there could be four fuses I cannot find the other one manual says its a optional thing I don't mess inside the scope as of yet with power applied I will get some pics up soon
5 ohms with the scope OFF is likely a major fault, if you are reading the two wires that connect the scope to the AC wall power. Unless the power switch is fused or broken and always in the on position.
I'd say you're over ur head on this one.
Best to find some local help or skip ahead to another scope.
Shipping it for repair will likely push the cost over the value of the scope, unless it is a very very simple fault... unless someone donates their efforts.
...sorry for bad news.
_-_-bear
I'd say you're over ur head on this one.
Best to find some local help or skip ahead to another scope.
Shipping it for repair will likely push the cost over the value of the scope, unless it is a very very simple fault... unless someone donates their efforts.
...sorry for bad news.
_-_-bear
Good going.
How are the sweep controls set? i.e. Maybe it was in x-y mode. if you apply a voltage to a vertical input (with DC or AC coupling selected for that channel) can you get the dot to move by the correct amount?
If you don't have the official Tektronix service manual for your scope, dowload either the 475A or 475 service manual. If you can't find a 475A service manual, the 475 is similar-enough to the 475A that its service manual will still be very helpful. You should also get the operator's manual.
There is a 475 manual at tek.com, after free registration. And the BAMA Achive site has some 475 manuals. And someone else posted another link, earlier, that might be for a 475A manual.
How are the sweep controls set? i.e. Maybe it was in x-y mode. if you apply a voltage to a vertical input (with DC or AC coupling selected for that channel) can you get the dot to move by the correct amount?
If you don't have the official Tektronix service manual for your scope, dowload either the 475A or 475 service manual. If you can't find a 475A service manual, the 475 is similar-enough to the 475A that its service manual will still be very helpful. You should also get the operator's manual.
There is a 475 manual at tek.com, after free registration. And the BAMA Achive site has some 475 manuals. And someone else posted another link, earlier, that might be for a 475A manual.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.