Topics

Changing the battery of a 2465B

Alberto I2PHD
 

I have a 2465B 'scope that I bought second hand about 20 years ago. It has always worked flawlessly, no signs of the dreaded 04 error at power on.
Considering that maybe the previous owner did use it for a number of years before selling it to me, I am fearing that the battery that holds the calibration data is near to the end of its life....

So, my question is... is there a recommended procedure to change the battery with a fresh one without losing the calibration data ?
I don't have the zillion test equipment that Tektronix deems as necessary to perform a new calibration, and sending it to someplace in the States to have it calibrated would cost me for shipping alone an amount similar to the actual price of the instrument...

Thanks for any suggestions...


--
/*73 Alberto I2PHD*
Keyboard Not Found : Press F1 to continue/

Paul Amaranth
 

If your NVRAM is still viable, dump the contents using a prom programmer and
then put the data into a new one before installing it.

It's not too hard to cobble up a suitable device using an arduino.

When you take out the old one, put in a good quality socket.

Paul

On Mon, May 20, 2019 at 01:10:46PM +0200, Alberto I2PHD wrote:
I have a 2465B 'scope that I bought second hand about 20 years ago. It has
always worked flawlessly, no signs of the dreaded 04 error at power on.
Considering that maybe the previous owner did use it for a number of years
before selling it to me, I am fearing that the battery that holds the
calibration data is near to the end of its life....

So, my question is... is there a recommended procedure to change the battery
with a fresh one without losing the calibration data ?
I don't have the zillion test equipment that Tektronix deems as necessary to
perform a new calibration, and sending it to someplace in the States to have
it calibrated would cost me for shipping alone an amount similar to the
actual price of the instrument...

Thanks for any suggestions...


--
/*73 Alberto I2PHD*
Keyboard Not Found : Press F1 to continue/





!DSPAM:5ce28b4e161396325818081!
--
Paul Amaranth, GCIH | Manchester MI, USA
Aurora Group of Michigan, LLC | Security, Systems & Software
paul@... | Unix & Windows

Chuck Harris
 

I presume that your 2465B is from before serial number B050000, and
has a battery and cmos ram setup, rather than the later Dallas NVRAM.

If that is so, it is trivial to replace the battery without losing
your calibration data... not that the data is all that valuable on
a scope so long out of calibration.

What you do is remove the A5 controller board, being sure not to
short the connections on the bottom of the board to any metal surface,
and set it down on a wooden board... [less static on wood, than on plastic,
and you sure don't want to use metal...]

Using a set of micrograbber clip leads, connect the minus lead of a 3V
battery to any convenient ground on the A5 board, and the Plus lead
to either of the cathodes of D2770, or D2371. You can solder a wire,
if you are afraid of your micrograbber clips, I don't as I think that
is a more dangerous act, than using a micrograbber clip. Just be sure
that your clips have a good J hook on their metal part.

Unsolder the battery, and install a new battery. Remove the micrograbber
clips.

Don't use a power supply for the 3V, just use a pair of AA cells, or
any lithium cell. Your soldering iron tip will be grounded (if it isn't,
you should throw it away), and may your calibration constants, by shorting
the battery to ground through the power supply... while you unsolder it.

And that is all.

The replacement battery is made by Eagle-Pitcher, and is readily available.

-Chuck Harris

Alberto I2PHD wrote:

I have a 2465B 'scope that I bought second hand about 20 years ago. It has always
worked flawlessly, no signs of the dreaded 04 error at power on.
Considering that maybe the previous owner did use it for a number of years before
selling it to me, I am fearing that the battery that holds the calibration data is
near to the end of its life....

So, my question is... is there a recommended procedure to change the battery with a
fresh one without losing the calibration data ?
I don't have the zillion test equipment that Tektronix deems as necessary to perform
a new calibration, and sending it to someplace in the States to have it calibrated
would cost me for shipping alone an amount similar to the actual price of the
instrument...

Thanks for any suggestions...

 

Chuck - Does the same hold true for a 2445? One of mine is giving me a battery error. Also, can you provide more information on the Eagle-Pitcher replacement battery? I couldn't find anything suitable cross-referencing the Tek part number so I bought a AA size Lithium battery, planning to use an AA battery holder with it, but if there is a correct battery I would rather go with that.

TIA, Lee

Alberto I2PHD
 

On 2019-05-20 15:20, Chuck Harris wrote:
I presume that your 2465B is from before serial number B050000, and
has a battery and cmos ram setup, rather than the later Dallas NVRAM.
Yes, the SN is B012133.
Other than telling me that it was made in Beaverton, Ohio, I don't how to interpret that number... year of production ? Special features ?
If that is so, it is trivial to replace the battery without losing
your calibration data... not that the data is all that valuable on
a scope so long out of calibration.
This brings to another question... when the 04 error is displayed ? When the checksum of the RAM is invalid, or when the instrument is actually out of the specifications ?
And in this latter case, how can the firmware tell that ?
Don't use a power supply for the 3V, just use a pair of AA cells, or
any lithium cell. Your soldering iron tip will be grounded (if it isn't,
you should throw it away), and may your calibration constants, by shorting
the battery to ground through the power supply... while you unsolder it.
Yes, I will use a couple of AAA cells for that, and a Weller soldering iron.
The replacement battery is made by Eagle-Pitcher, and is readily available.
Well, I have never opened the instrument, and I thought, apparently wrongly, that a CR2032 cell could do.
They are sold around here at the supermarket, a 6-pack for 3 Euro. Is that cell sold by Eagle-Pitcher different from a CR2032 ?

Thanks for your suggestions.


--
/*73 Alberto I2PHD*
Keyboard Not Found : Press F1 to continue/

Chuck Harris
 

A 2445<<B>> with a serial number below B050000, yes.

The 2445/55/65 (Note no "B" suffix) uses no battery,
just a device called an EAROM.

-Chuck Harris

Lee Houde wrote:

Chuck - Does the same hold true for a 2445? One of mine is giving me a battery error. Also, can you provide more information on the Eagle-Pitcher replacement battery? I couldn't find anything suitable cross-referencing the Tek part number so I bought a AA size Lithium battery, planning to use an AA battery holder with it, but if there is a correct battery I would rather go with that.

TIA, Lee



Chuck Harris
 

If you are getting *any* of the Test04 errors, your calibration
is gone, or was never there in the first place.

There about 180 locations in the saved RAM, NV, or CMOS,
that contain important values related to your calibration.
Each has a parity bit associated with it, and the entire block
of constants has a checksum associated with it.

If any of those checksums has changed, your RAM has lost its power
and forgotten all or some of its data. The thing is, you can't
tell which it is, so you have to assume it is all bad.

The only cogent way to tell the age of your scope is to look at
the dates on the soldered in IC's, and that is slightly earlier
than your scope was sold. The hybrids are not a safe indication,
because they could have been swapped... though if most have
similar dates, they are probably original.

-Chuck Harris

Alberto I2PHD wrote:

On 2019-05-20 15:20, Chuck Harris wrote:
I presume that your 2465B is from before serial number B050000, and
has a battery and cmos ram setup, rather than the later Dallas NVRAM.
Yes, the SN is B012133.
Other than telling me that it was made in Beaverton, Ohio, I don't how to interpret
that number... year of production ? Special features ?
If that is so, it is trivial to replace the battery without losing
your calibration data... not that the data is all that valuable on
a scope so long out of calibration.
This brings to another question... when the 04 error is displayed ? When the checksum
of the RAM is invalid, or when the instrument is actually out of the specifications ?
And in this latter case, how can the firmware tell that ?
Don't use a power supply for the 3V, just use a pair of AA cells, or
any lithium cell. Your soldering iron tip will be grounded (if it isn't,
you should throw it away), and may your calibration constants, by shorting
the battery to ground through the power supply... while you unsolder it.
Yes, I will use a couple of AAA cells for that, and a Weller soldering iron.
The replacement battery is made by Eagle-Pitcher, and is readily available.
Well, I have never opened the instrument, and I thought, apparently wrongly, that a
CR2032 cell could do.
They are sold around here at the supermarket, a 6-pack for 3 Euro. Is that cell sold
by Eagle-Pitcher different from a CR2032 ?

Thanks for your suggestions.

Tony Fleming
 

Is 2465 DMS equipped with battery or has CMOS?
Thanks.

On Mon, May 20, 2019 at 2:29 PM Chuck Harris <cfharris@...> wrote:

A 2445<<B>> with a serial number below B050000, yes.

The 2445/55/65 (Note no "B" suffix) uses no battery,
just a device called an EAROM.

-Chuck Harris

Lee Houde wrote:
Chuck - Does the same hold true for a 2445? One of mine is giving me a
battery error. Also, can you provide more information on the Eagle-Pitcher
replacement battery? I couldn't find anything suitable cross-referencing
the Tek part number so I bought a AA size Lithium battery, planning to use
an AA battery holder with it, but if there is a correct battery I would
rather go with that.

TIA, Lee