2465BDV slow reaction


Sergey Kubushyn
 

Hi everybody,

I have a 2465BDV (early series, serial B013522) that has a weird problem.
Everything works fine, display is crisp, readout/cursors/etc everything
works. The problem is it is very slow to response to controls. E.g. when
turning vertical position pot it doesn't react immediately so trace does not
move. Then, after a second (may be half-second but very noticeable and long
delay) it jumps to a new location. That is true for all controls e.g. it is
very difficult to use trigger level. It is also slow to respond to switches
(e.g. trigger mode) and when I turn off e.g. cursors they dissappear but the
big character reading stays on the screen for a second or so after cursor
turned off.

If I turn a pot VERY slowly it follows it i.e. there is a very long lag on
reading the control panel.

Also all LEDs flash momentarily when it loses sync or any control changing
LED state is activated (i.e. when there is a change in which LEDs are lit on
the control panel.)

Other than that everything works fine. All voltages are normal, no ripple,
LVPS was recapped recently so there is no problems with the power. All caps
were like new so no recap was actually required but once I've already pulled
that PS off the scope I proceeded with the recap.

It's been behaving exactly the same before that so that recap didn't change
anything.

Have anybody experienced anything like that?

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honolulusnowwhite
 

Hi Sergey,

I haven't had this problem. I suggest that you follow the Preliminary Troubleshooting chart in the repair manual. Among other things, the chart has you check the clock speed of the microprocessor and the signals at selected other pins.

The microprocessor is supposed to scan the front panel switches every 32 ms while the front panel pots are supposed to be scanned every 16 ms.

Good luck,

Patrick Wong AK6C

--- In TekScopes@..., Sergey Kubushyn <ksi@...> wrote:

I have a 2465BDV (early series, serial B013522) that has a weird problem.
Everything works fine, display is crisp, readout/cursors/etc everything
works. The problem is it is very slow to response to controls. E.g. when
turning vertical position pot it doesn't react immediately so trace does not
move. Then, after a second (may be half-second but very noticeable and long
delay) it jumps to a new location...