Perzackly! That electric field is what does the deflection when it is the right polarity and magnitude at any given instant. When the voltages at the plates are not correct, neither is the position

Thanks Egge, I searched eBay for Tek TNGTDS01, but did not think of searching for "Operator Training Kit."  It also occurred to me that a member of the group might have one of these kits they might

Thanks Chuck. I have taken your advice and concentrated on the +5V circuit. Current conditions +32 TP reads 34.1, +5 TP 3.8, -5 TP -4.7 and 95 TP reads 8.8. I have read out all components in the +5

Thank you Larry, Michael and Roger for your explanations and help. I will report back when I get to it shortly.

Actually a ramp, more than a triangle. -- Michael Lynch Dardanelle, AR

The beam is deflected by differing potentials between the two plates. if the dot is off the screen, then one plate is much higher or lower than the other. Depends on which way the beam is being

That is ultimately my plan. Gonna cut a screw down as a stud and put the same resin in the there and cure the whole thing in a UV chamber, should get rid of any issues with the square edges in the

I could be wrong, but I thought Larry's point was that the rotation and Y adjust coils are in the nature of fine geometry adjustments and are not going to send the beam off screen unless you put a

Ohh, ok. Thank you for making that clear. So why do I need to check the voltage at the plates? I’m a bit confused now... Trying to learn something in the process too.

My point was that this is not going to be the cause of the trace moving offscreen....

Hi Flyte, I've managed to find the main fault with my TDS6604 - one of the trigger chips was fried, the infamous Tek # 156-8278-00 I've also managed to locate a couple of Acq. boards for TDS6604, but

Will definitely be extra careful. Thank you.

Be careful getting probes on and off scope deflection plates. I got a probe snagged and broke off the pin on the scope! wailing and gnashing of teeth. Simon

Hi Bruce, This is the Kit. One Board and a set of Instructions to 4 TDS-Series. Pops up regularly on

Accès to the plates is quite easy. Will do what you suggested and report back. Thank you Roger

Yes Roger, you’re right. I forgot to mention that when it does work for a few seconds, it’s usually 1 or 2, and it’s extremely rare. 99% of the time it’s instantaneous.

Your first email seemed to imply that sometimes it was working for a few seconds, hence the before and after suggestion. Anyway, measure all the low voltage rails and if any are significantly low

Thank you Roger. I’ll try to check that. But it’s extremely fast, and most of the time instantaneous upon power on.

You need to check the state of all low voltage supplies before and after the fault appears. The power light is an LED fed from the +5V rail, so try watching the 5V rail during the transition from

485 covers don’t have part numbers embossed on them. You have to measure the dimensions of the metal rim around the ‘scope panel and look for a cover that has those dimensions on the inside of the