Topics

Backup Battery in Tek 2245A

mcdadeclinton
 

Hi All, I have a Tektronix model 2245A Oscilloscope and I wonder if it uses a backup battery and where it is located if it does use one. I have a service manual that lists a backup battery but I have not been able to locate it in the scope or in a diagram for location in the manual.
Maybe it is only an option in some versions of them?

rpoz28cam
 

Clinton,
 
I do believe the 2245A has a nvram with internal lithium battery mounted on the controller similar to my 2467B.  It is DS12XX series part that also contains calibration constants programmed into this part.  I have a similar situation with my 2467B. There are a few people on here that are quite knowledgeable regarding this topic.
 
Jon

From: Clinton
To: TekScopes@...
Sent: Wednesday, September 7, 2011 8:59 AM
Subject: [TekScopes] Backup Battery in Tek 2245A

 
Hi All, I have a Tektronix model 2245A Oscilloscope and I wonder if it uses a backup battery and where it is located if it does use one. I have a service manual that lists a backup battery but I have not been able to locate it in the scope or in a diagram for location in the manual.
Maybe it is only an option in some versions of them?



gwangju3 <gwangju3@...>
 

2245A or 2445A? These are different, which scope do you have and which manual do you have? These two scopes are mixed up all the time here that is why I ask.

--Victor

--- In TekScopes@..., "Clinton" <mcdadeclinton@...> wrote:

Hi All, I have a Tektronix model 2245A Oscilloscope and I wonder if it uses a backup battery and where it is located if it does use one. I have a service manual that lists a backup battery but I have not been able to locate it in the scope or in a diagram for location in the manual.
Maybe it is only an option in some versions of them?

gwangju3 <gwangju3@...>
 

See what I mean. 2245A and 2445A are not the same.

A 2245A i not like a 2467B. A 2445A is a little like a 2467B.

--Victor

--- In TekScopes@..., J <rpoz28cam@...> wrote:

Clinton,
 
I do believe the 2245A has a nvram with internal lithium battery mounted on the controller similar to my 2467B.  It is DS12XX series part that also contains calibration constants programmed into this part.  I have a similar situation with my 2467B. There are a few people on here that are quite knowledgeable regarding this topic.
 
Jon

From: Clinton <mcdadeclinton@...>
To: TekScopes@...
Sent: Wednesday, September 7, 2011 8:59 AM
Subject: [TekScopes] Backup Battery in Tek 2245A


 
Hi All, I have a Tektronix model 2245A Oscilloscope and I wonder if it uses a backup battery and where it is located if it does use one. I have a service manual that lists a backup battery but I have not been able to locate it in the scope or in a diagram for location in the manual.
Maybe it is only an option in some versions of them?

rpoz28cam
 

Ah yes, thank you for clearing that up Victor.
 
 
 

From: gwangju3
To: TekScopes@...
Sent: Wednesday, September 7, 2011 9:21 AM
Subject: [TekScopes] Re: Backup Battery in Tek 2245A

 
See what I mean. 2245A and 2445A are not the same.

A 2245A i not like a 2467B. A 2445A is a little like a 2467B.

--Victor

--- In TekScopes@..., J wrote:
>
> Clinton,
>  
> I do believe the 2245A has a nvram with internal lithium battery mounted on the controller similar to my 2467B.  It is DS12XX series part that also contains calibration constants programmed into this part.  I have a similar situation with my 2467B. There are a few people on here that are quite knowledgeable regarding this topic.
>  
> Jon
>
> From: Clinton
> To: TekScopes@...
> Sent: Wednesday, September 7, 2011 8:59 AM
> Subject: [TekScopes] Backup Battery in Tek 2245A
>
>
>  
> Hi All, I have a Tektronix model 2245A Oscilloscope and I wonder if it uses a backup battery and where it is located if it does use one. I have a service manual that lists a backup battery but I have not been able to locate it in the scope or in a diagram for location in the manual.
> Maybe it is only an option in some versions of them?
>



Francis <jekker@...>
 

Hi,

the battery is located under the logic board, the upper one.
You can see it when the case is removed, front left, near the CRT.

--- In TekScopes@..., "Clinton" <mcdadeclinton@...> wrote:

Hi All, I have a Tektronix model 2245A Oscilloscope and I wonder if it uses a backup battery and where it is located if it does use one. I have a service manual that lists a backup battery but I have not been able to locate it in the scope or in a diagram for location in the manual.
Maybe it is only an option in some versions of them?

mcdadeclinton
 

Wow, thank you guys for all your great responses. I do have a 2245A and I know there is a big difference between the 2245A and a 2445A.
As one member said the backup battery is on the underside of the logic board as big as day. I don't see how I could have missed it. I only saw it when I removed the mounting screws from the board and lifted it up.
Thanks everyone.

tom jobe
 

Another thought on those 224x series batteries, is that I don't believe it
is involved in storing any calibration data. I have changed those 224x
batteries without any apparent loss of anything, and I believe the battery
only helps to save the current setup across oscilloscope shutdowns.
Comments anyone?
tom jobe...

----- Original Message -----
From: "Clinton" <mcdadeclinton@...>
To: <TekScopes@...>
Sent: Wednesday, September 07, 2011 9:44 AM
Subject: [TekScopes] Re: Backup Battery in Tek 2245A




Wow, thank you guys for all your great responses. I do have a 2245A and I
know there is a big difference between the 2245A and a 2445A.
As one member said the backup battery is on the underside of the logic board
as big as day. I don't see how I could have missed it. I only saw it when I
removed the mounting screws from the board and lifted it up.
Thanks everyone.

tom jobe
 

While we are talking about those 224x batteries, they seem to last for a
very long time and will check out in 3.2 to 3.5 volt range when you open an
old 224x scope up. I don't think I have ever seen one of those batteries
leaking either. Many of the originals were a yellow Panasonic 2/3 A lithium
battery.
I have never checked a brand new one, but the Maxell new old stock
replacement batteries I bought at the flea market check at around 3.7 volts.
The Maxell's have 3.6 volts given on the label as the nominal voltage, the
Panasonics do not show a nominal voltage on the battery.
I have seen the exact replacement battery on the Internet at one of the
battery sellers for a very ordinary price.
The amount of room you have available on the 224x's, gives you endless
possibilities to adapt most anything to replace the original battery.
tom jobe...
PS Some of the military 224x's use two un-obtainable coin batteries, and
they seem to always be leaking and making a mess of the Processor board. All
of the solder points are there to convert it to the commercial model single
battery, or to do any other solution you might have in mind.

----- Original Message -----
From: "Clinton" <mcdadeclinton@...>
To: <TekScopes@...>
Sent: Wednesday, September 07, 2011 9:44 AM
Subject: [TekScopes] Re: Backup Battery in Tek 2245A




Wow, thank you guys for all your great responses. I do have a 2245A and I
know there is a big difference between the 2245A and a 2445A.
As one member said the backup battery is on the underside of the logic board
as big as day. I don't see how I could have missed it. I only saw it when I
removed the mounting screws from the board and lifted it up.
Thanks everyone.

mcdadeclinton
 

The battery in my scope is the big yellow Panasonic lithium. It has the marking "3V" Meaning 3 volts? It is clean and measures 3.1 volts. I think I will leave it alone. The scope works ok but seems to do some erratic things when it is turned on cold but settles down in a short time. When I have time I may do some checks on the power supply.

tom jobe
 

Do a Google search on "Lithium battery voltage", and you will see that the
end is in sight when you get down to 3.1 volts. No need to panic, but you
will probably need to deal with it in the next year or so.
My guess is that you have a marginal capacitor in your power supply, which
will be a cheap and easy fix.
tom jobe...

----- Original Message -----
From: "Clinton" <mcdadeclinton@...>
To: <TekScopes@...>
Sent: Wednesday, September 07, 2011 4:56 PM
Subject: [TekScopes] Re: Backup Battery in Tek 2245A




The battery in my scope is the big yellow Panasonic lithium. It has the
marking "3V" Meaning 3 volts? It is clean and measures 3.1 volts. I think I
will leave it alone. The scope works ok but seems to do some erratic things
when it is turned on cold but settles down in a short time. When I have time
I may do some checks on the power supply.

Tom Miller <tmiller@...>
 

It depends on the chemistry as to what the voltage should be.
 
 
Li-MnO2 are 3.3 volts when new and below 3.0 v near the end. So 3.1 volts could have a fair amount of time left.
 
Li-SOCl2 run about 3.7 volts new and by 3 volts, you don't have much time left.
 
I usually like the Tadiran batteries. They advertise a minimum 25 year life at rated load. In 25 years, I won't be able to see the screen anyway :).
 
 
Regards,
Tom M
 
 
 
 

----- Original Message -----
From: tom jobe
Sent: Wednesday, September 07, 2011 8:11 PM
Subject: Re: [TekScopes] Re: Backup Battery in Tek 2245A

 

Do a Google search on "Lithium battery voltage", and you will see that the
end is in sight when you get down to 3.1 volts. No need to panic, but you
will probably need to deal with it in the next year or so.
My guess is that you have a marginal capacitor in your power supply, which
will be a cheap and easy fix.
tom jobe...

----- Original Message -----
From: "Clinton" <mcdadeclinton@...>
To: <TekScopes@...>
Sent: Wednesday, September 07, 2011 4:56 PM
Subject: [TekScopes] Re: Backup Battery in Tek 2245A

The battery in my scope is the big yellow Panasonic lithium. It has the
marking "3V" Meaning 3 volts? It is clean and measures 3.1 volts. I think I
will leave it alone. The scope works ok but seems to do some erratic things
when it is turned on cold but settles down in a short time. When I have time
I may do some checks on the power supply.

classe_dr9 <classe_dr9@...>
 

I have a 2246 Mod A that I bought new, it's 21+ years old so I thought that I'd replace the battery. I bought a brand new Panasonic BR-2/3A battery (what the manual called for and what's on the board), it measures 3.40 volts, I measured the original battery in circuit and it measures 3.38 volts so I left it alone.

--- In TekScopes@..., "Clinton" <mcdadeclinton@...> wrote:



The battery in my scope is the big yellow Panasonic lithium. It has the marking "3V" Meaning 3 volts? It is clean and measures 3.1 volts. I think I will leave it alone. The scope works ok but seems to do some erratic things when it is turned on cold but settles down in a short time. When I have time I may do some checks on the power supply.

mcdadeclinton
 

It would seem as though those batteries might last forever...

--- In TekScopes@..., "classe_dr9" <classe_dr9@...> wrote:

I have a 2246 Mod A that I bought new, it's 21+ years old so I thought that I'd replace the battery. I bought a brand new Panasonic BR-2/3A battery (what the manual called for and what's on the board), it measures 3.40 volts, I measured the original battery in circuit and it measures 3.38 volts so I left it alone.

--- In TekScopes@..., "Clinton" <mcdadeclinton@> wrote:



The battery in my scope is the big yellow Panasonic lithium. It has the marking "3V" Meaning 3 volts? It is clean and measures 3.1 volts. I think I will leave it alone. The scope works ok but seems to do some erratic things when it is turned on cold but settles down in a short time. When I have time I may do some checks on the power supply.