Re: 2465B/2467B NVRAM image, different cable, CAL proceedure

Chuck Harris

A full cal is a much better and more meaningful test of whether
your rework was done properly. Typically, what you did to the A5
board would be fully tested in the first section of calibration
where you calibrate the power supply and the DAC reference.

Your scope coming up with a the Test04 ERR 1x error does nothing
to prevent you from using your scope. Just dismiss the message and
move on. If you clear your NVRAM with your programmer, and install
it in your scope, default calibration constants will be applied, and
that is just as good as using a bogus NVRAM image from some other
scope.... It will allow you to do the only meaningful function you
can do with an uncalibrated 2465B: test and calibrate your scope.

The only reason I can think of that these bogus images for NVRAMS exist
is so that the owner of a scope with broken calibration can demonstrate
the scope as working with old but good calibration. The only reason
I can think of to want to do that is deceit.

You cannot calibrate the transient response of a 2465[ ,A,B] scope with
a PG506, without a fast rise time pulser such as the TD pulser. You
would be better off leaving the Transient Response section alone until
you have the necessary calibration equipment.

As an aside: I have ordered one of Leo Bodner's inexpensive pulsers,
in order to evaluate it's use for transient calibration of 2465's.

I will report my findings and opinion to the group.

-Chuck Harris

Froggie the Gremlin wrote:

Hello Chuck and MachineGuy!

1/ Yes suspicious looking hex data in both NVRAMs, so I assume the data is useless.

2/ I found both 2467B and 2465B default NVRAM images.

3/ Agree on CAL, I would use the PG506 instead of the TD pulser for the fast rise cals.

4/ Identified OPT 06 as CTT, there is an option board tucked near the PSU. Cable from option board interferes with NVRAM on low profile machined pin socket. Have to fix that.

5/ Plan is to try the default images just to check if the hardware rework on A5 board is OK, then to setup to do the full CAL.

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