Except for transient response, the calibration can be done with a vertical amplifier by connecting test points for an AC/DC multimeter to the differential signals at the interface. I use a 7A16A (1) but any of the single trace high input impedance vertical amplifiers are suitable. The dual trace amplifiers will work also but access is more difficult.
Transient response calibration is more difficult and would require a 7A19 or 7A29 and an external adapter to sample the differential signal between the plug-in and interface using the procedure Tektronix used for calibrating the 7104. (2) I just settled for verifying the transient response at the BNC with my fastest vertical amplifier plug-in which is a 7A24 and fastest reference level pulse generator; it looked good enough to me so I did not mess with it.
(1) The 20 MHz bandwidth limit of the 7A16A helps a lot by producing a low noise trace so the 7A15A with its 10 MHz bandwidth limit may be even better.
(2) Tektronix made a special plug-in extender for 7104 calibration with coaxial connections for the differential vertical and trigger signals that could be disconnected to be swapped or sampled.
I understand how to do this, but can't find some info. What is the voltage/division for vertical and horizontal deflection of the scope. Find some info for 50mv/div, but not sure for this (after some reading of the calibration procedure for 067-0587-02 — Calibration Fixture I'm sure now - it is 50mv/div).
I can try to make this extender - have some mainframe and plugins for spares and think that can be use connectors from it and to make a pcb to put all together with bnc connectors inside the extender.
I understand how to do this, but can't find some info. What is the voltage/division for vertical and horizontal deflection of the scope. Find some info for 50mv/div, but not sure for this (after some reading of the calibration procedure for 067-0587-02 — Calibration Fixture I'm sure now - it is 50mv/div).
I think the easiest place to find it is in the standardizer service manuals and as I recall, it is 25mV/div per side or 50mV/div differential. (1)
I can try to make this extender - have some mainframe and plugins for spares and think that can be use connectors from it and to make a pcb to put all together with bnc connectors inside the extender.
I just left the cover off of the mainframe and off of the 7A16A vertical plug-in so my multimeter leads could reach the test points that I added.
DC volts on my multimeter allowed zeroing the output from the vertical plug-in to do the zero calibration of the mainframe and AC volts allowed adjusting the function generator and plug-in to produce exactly 1 div, 2 div, ect. peak-to-peak low frequency square waves for vertical calibration. An average responding AC meter reads 1/2 the peak-to-peak value 11% high and an RMS responding AC meter reads 1/2 the peak-to-peak value.
Then I moved the plug-in to a horizontal slot to do the same for the mainframe's horizontal circuits.
The transient response calibration needs a standardizer or the extender with the signal splitters to drive another faster oscilloscope.
(1) Confusingly, Tektronix sometimes calls this push-pull but that is fair since people now confuse differential with difference.
I think the easiest place to find it is in the standardizer service manuals and as I recall, it is 25mV/div per side or 50mV/div differential. (1)
Yes I find this in 068-0587-02 SM - page 5.20 and 5.21. About difference and differential - maybe because of my bad English, but I know what is and how to measure differential voltage
. This will be no problem to check the scope and to calibrate it.
The transient response calibration needs a standardizer or the extender with the signal splitters to drive another faster oscilloscope.
Think to make this extender and to use CG5001 with pulse head in fast edge mode and other oscilloscope to check this. Just need to find a time to make it. Think that is the way to trigger the scope to show good edge w/o 7s11 and 7t11.
The transient response calibration needs a standardizer or the extender with the signal splitters to drive another faster oscilloscope.
Think to make this extender and to use CG5001 with pulse head in fast edge mode and other oscilloscope to check this. Just need to find a time to make it. Think that is the way to trigger the scope to show good edge w/o 7s11 and 7t11.
Just to be clear, I was writing about using your CG5001 to drive the fastest 7000 vertical amplifier plug-in that you have, calibrating the transient response of the vertical amplifier plug-in with the extender, and then using the combined CG5001 and vertical amplifier plug-in to calibrate the mainframe. The flaw with this method is the requirement for a faster reference oscilloscope which is why Tektronix used a 7S11/7T11/S4 sampling oscilloscope.
I am not sure if using the extender to directly drive the mainframe from the CG5001 fast edge would work well. The standardizer plug-ins go to considerable effort to create an accurate differential pulse and the CG5001 only produces an accurate singled ended pulse. The PG506 creates an differential pulse but it may not be time aligned accurately and it is too slow for calibration at 500 MHz.
Note that if you only have a limited set of vertical amplifier plug-ins, then it is more important that they all agree with each other in producing a clean transient response on your 7904 mainframe. If they do, and this is exactly what your CG5001 was intended to test, then messing with the transient response of the 7904 will not be necessary and may just lead to trouble.
The transient response calibration needs a standardizer or the extender with the signal splitters to drive another faster oscilloscope.
Think to make this extender and to use CG5001 with pulse head in fast edge mode and other oscilloscope to check this. Just need to find a time to make it. Think that is the way to trigger the scope to show good edge w/o 7s11 and 7t11.
Just to be clear, I was writing about using your CG5001 to drive the fastest 7000 vertical amplifier plug-in that you have, calibrating the transient response of the vertical amplifier plug-in with the extender, and then using the combined CG5001 and vertical amplifier plug-in to calibrate the mainframe. The flaw with this method is the requirement for a faster reference oscilloscope which is why Tektronix used a 7S11/7T11/S4 sampling oscilloscope.
I am not sure if using the extender to directly drive the mainframe from the CG5001 fast edge would work well. The standardizer plug-ins go to considerable effort to create an accurate differential pulse and the CG5001 only produces an accurate singled ended pulse. The PG506 creates an differential pulse but it may not be time aligned accurately and it is too slow for calibration at 500 MHz.
Note that if you only have a limited set of vertical amplifier plug-ins, then it is more important that they all agree with each other in producing a clean transient response on your 7904 mainframe. If they do, and this is exactly what your CG5001 was intended to test, then messing with the transient response of the 7904 will not be necessary and may just lead to trouble.
yes, I think to do this with 7a19 and 7b92a instaled on 7904. I can't use CG w/o amplifier (or maybe I dont know how to do this). Just think to use CG because I have some other generators (pg501, pg508, hp 8012 and one philips 5770), but CG with pulshead installed have smallest Rise/fail time (~200ps). Something else - I can see positive and negative edge with GC and pulse head. It trigger well to show this - I use this to check other scopes before (4xx, 2236, 2445, 2455), but never with 7000. Will check when find a time for this and will write the results.
Last night make some photos of what I mean to use for checking 7904. Make it with a scope that was on the desk for repairing - it is not calibrated but show good response. First two photo is in fast edge mode positive and negative edge and 50uS/div. Second two is in voltage mode 100uS/div. This is the best that I have at home, try some other generators but they have lower rise/fail time than the pulse head of the CG.
On 7904 maybe will get better responce, because the rise/fail time in the pulse head specifications is <= 200ps. Tonight just for info will check what will show 2455A or 485. Maybe will be better than 2236.