Re: 2440 and 2465B battery/ram replacement

Szabolcs Szigeti

Hi Mark,

I can't help in replacing the RAMs, but I have some experience with the
2440/2432 etc DSOs. Don't be afraid to replace the RAM without saving it's
content, it is much easier to get calibrated than the 2465.
The first time I calibrated a 2440 I used a DC supply, and an old, low end
function generator's square wave output. Since then I have much improved
instruments, but it was possible to get it calibrated with minimum
Especially, that if it is has not been calibrated for long you will
probably need to do an internal adjustment and readjust the screen geometry
and the CCD timing anyway (for that you'll need some kind of a signal
generator) which requires clearing the nvram as a first step, so there is
absolutely no need to save the ram or worry about losing its content. There
is absolutely no point in saving and reloading the old data.


Mark Vincent <> ezt írta (időpont: 2021. márc.
26., P, 2:45):

I have both of these and would like to get these replaced with the new
style of chip that does not need the back-up battery. The (real) 2465B is
still good. I do not know how long it will keep the data before becoming
dead. The 2440 needs replacing. I know these original devices will go bad
soon. I do not have or access to a programmer. I know I have the newer A5
board in the B with S/N 063838 (1994). I am in the mid-Atlantic area of the
US. The caps and resistors in both have already been done. Mr. Yachad's
2465B site was used. Thank you Mr Yachad. I do not know what I would send.
The whole piece, board, what. Is there anyone willing to do this and give
me a price on these? I do not know if calibration is needed after the chip
replacement. I know enough people in this group are good to expert at using
and knowing the 2465B features. I got this one because of the praise it

The 2440 I have used some. The B is recent and I need to learn the
features. This is new to me. I am used to the 7000 series and older. The
2440 has some FAIL modes. I think the CCDs are good. It likely needs
calibration to clear the fail. This one still shows signals like should. I
know I need to learn what all this one can do when it is working right.

I have adjusted the power supplies to within a couple of mV to exact
of the adjustments on each scope. I do this on other models as well.

If anyone wants to contact in private, you can use the email. I will
give my telephone number in a private email if any want it. That is a much
faster way to get me and discuss anything necessary.


Join to automatically receive all group messages.