Author Topic: Quick question about HP 3468A (Read 25435 times)

Dave · « **Reply #25 on:** February 28, 2013, 12:34:53 am »

c4757p, could you measure the dimensions of the original battery? I need to replace batteries in two meters and I want to buy the right batteries for the job.

c4757p · « **Reply #26 on:** February 28, 2013, 01:14:23 am »

Very nice on the 3478A. Looks like there's a bit more room to move things around - and that hole you put the cable tie through was convenient indeed!

Dave, of course! I'll grab the measurements tonight.

willb · « **Reply #27 on:** February 28, 2013, 02:10:33 am »

Those holes were indeed very practical! Made everything so easy and clean.

Aren't the batteries the same in the 3468A and 78A?? The one I used fit absolutely beautifully in my meter. I don't think the old battery was original, but the dimensions of the old vs the new are the exact same. Attached is the old battery.

c4757p · « **Reply #28 on:** February 28, 2013, 02:41:01 am »

It looks identical. Mine IIRC was blue (could be black, now that I think about it) but was otherwise the same shape, size, and brand.

Dave · « **Reply #29 on:** February 28, 2013, 04:56:21 pm »

Judging from the picture, I assume that is a 2/3 AA battery (33mm or 1.3" in lenght). Is this the correct size?
It could also be a 1/2 AA battery (25mm or 1" in lenght). Which of the two should I buy?

c4757p · « **Reply #30 on:** February 28, 2013, 05:13:46 pm »

Ah crap, I forgot to get the measurements! Here, I just did now: Length 32.5mm (29.4mm excluding the + bump), diameter 16.3mm.

Dave · « **Reply #31 on:** February 28, 2013, 05:19:52 pm »

No worries.

2/3 AA it is. Thanks!

tribbles · « **Reply #32 on:** March 02, 2013, 06:07:35 pm »

I have a 3468a and the battery in it is a SAFT LX1634. Is that an original or has it been replaced? If they replaced it they did a good job looking at the board and joint.

c4757p · « **Reply #33 on:** March 02, 2013, 07:50:50 pm »

Well, it's not the same type mine had, but it's just a battery - they certainly could have swapped for a different one at some point.

ModemHead · « **Reply #34 on:** March 02, 2013, 11:11:53 pm »

Quote from: tribbles on March 02, 2013, 06:07:35 pm

I have a 3468a and the battery in it is a SAFT LX1634. Is that an original or has it been replaced? If they replaced it they did a good job looking at the board and joint.

I also have a 3468A with a SAFT LX1634 in it. Looks original to me. I just ordered a BR-2/3A to replace it. (Digikey P226-ND)

edit: I documented the replacement procedure here

Dave · « **Reply #35 on:** March 19, 2013, 02:50:26 pm »

I replaced the batteries in both my multimeters this weekend, but was only 50% successful at doing so.
I first tackled my 3468A and successfully replaced the battery. I kept the RAM alive by tack soldering a temporary AA battery pack to the leads of capacitor C550.
After I finished working on this meter, I tested it and everything appeared to be in order.

Feeling confident, I cracked open my 3468B. This time around, I decided to also take some photos of the process.
I soldered in the temporary battery pack, took a picture, and immediately desoldered the lithium battery. Just as I was holding the lithium battery in my hand, I noticed one of the AA batteries sitting NEXT to the battery holder. At that point, I wanted to bang my head on the bench. You can see the result of my stupidity in the images below.

Now I have to find a way to recalibrate my meter. Hopefully I can find some help at my uni.

bingo600 · « **Reply #36 on:** March 19, 2013, 07:53:22 pm »

Quote from: ModemHead on March 02, 2013, 11:11:53 pm

Quote from: tribbles on March 02, 2013, 06:07:35 pm
I have a 3468a and the battery in it is a SAFT LX1634. Is that an original or has it been replaced? If they replaced it they did a good job looking at the board and joint.

I also have a 3468A with a SAFT LX1634 in it. Looks original to me. I just ordered a BR-2/3A to replace it. (Digikey P226-ND)

edit: I documented the replacement procedure here

Thanx for the nice description & pics.
This inspired me to finally change the battery in my HP 3478A in the weekend

I'll use my Propane solder unit , and a spare 3v3 litihum diode-ored to the ram supply.
I even think i'll keep 230v mains on , while performing it.

/Bingo

c4757p · « **Reply #37 on:** March 19, 2013, 08:12:35 pm »

Quote from: Dave on March 19, 2013, 02:50:26 pm

Just as I was holding the lithium battery in my hand, I noticed one of the AA batteries sitting NEXT to the battery holder. At that point, I wanted to bang my head on the bench. You can see the result of my stupidity in the images below.

Now I have to find a way to recalibrate my meter. Hopefully I can find some help at my uni.

Oh, no!

That's not going to be easy. I hope you can find help.

ModemHead · « **Reply #38 on:** March 19, 2013, 09:28:28 pm »

Quote from: bingo600 on March 19, 2013, 07:53:22 pm

Thanx for the nice description & pics.

Glad you found it useful. Should be no problem, just double-check everything, don't get sloppy with the iron, and make sure your back-up power is actually connected before snipping! (@Dave I too hope you can find some help...)

bingo600 · « **Reply #39 on:** March 21, 2013, 01:21:39 pm »

I did change the battery in my HP 3478A successfully today.
https://www.eevblog.com/forum/beginners/changing-battery-in-a-hp-3478a-can-i-use-a-3v-lithium/

/Bingo

george graves · « **Reply #40 on:** April 13, 2013, 10:03:46 am »

I wonder how hard it would be to add a backlight a 3468A.

skipjackrc4 · « **Reply #41 on:** April 13, 2013, 02:50:49 pm »

Quote from: EEVblog on February 19, 2013, 09:12:05 am

That is a known wear issue on the HP3458A.

Dave.

Are the relays replaceable? I have one and had the same concerns.

grumpydoc · « **Reply #42 on:** April 13, 2013, 03:37:58 pm »

Quote

I wonder how hard it would be to add a backlight a 3468A.

If the display is similar to the 3478 I think basically impossible

Wh1sper · « **Reply #43 on:** July 10, 2013, 10:59:25 am »

Hello HP3468A owners.
I have this one, too.
Often I change from Volts to Resistor Measurement and back.
What's sometime happen is that no value is been shown.
I didn't found another solution than power off an power on again to awake the DMM.
Is this a known behavior to you, or it's just mine? Its ROM inside date around '97 as I remember right.

(Please apologize for not introducing myself first, I will catch it up soon.
Greetings

mianchen · « **Reply #44 on:** August 07, 2013, 09:23:19 pm »

Thank you everyone in this thread. After reading this thread, I've successfully replaced my battery for the HP3468A with a 1/2 AA Tandiran SL350P which is what I could get from Farnell UK at the time.

I guess it must be easier than putting in a 2/3 AA. With a half AA, you have a lot more room to work with and the leads are easier to solder in compared to solder tabs I think.

Before I did anything, I had a bit of oh @!&* moment when I accidentally shorted the battery - I realised that within 5 seconds. There was no spark, flame etc. and the temperature of the battery did not increased noticeably, if at all. But the voltage of the battery went down to 3.2V (3.6V nominal, 3.7V when I first tested it). It gradually came back to 3.65V after 10 minutes or so. I wasn't sure how much damage I did to the battery, and didn't think straight, used it to replace the old battery inside the HP meter.

Now when I think about it, I start to worry about the longevity of this new Tandiran - Should I be worried? should I get another one to replace this??

Any comments are welcome, TIA

Fsck · « **Reply #45 on:** August 07, 2013, 10:46:00 pm »

Quote from: willb on February 27, 2013, 08:50:12 pm

I just replaced my battery in my 3478A today. I wasn't sure on the age of the battery, so I did it to be on the safe side.

Here is the battery I used :

http://www.alliedelec.com/search/productdetail.aspx?SKU=70197006

It was the only place and only battery I found in stock that would work and ship to Canada. Anyhow, I powered up the meter and used a Weller Pyropen to solder the new battery. The whole process was painless. I soldered pieces of 22ga wire on the battery tabs and fixed the battery in place with some double stick tape and a zip tie. I turned the meter around once the battery was in place and soldered the wires to the PCB. 20 minutes later I had my meter back in service.

As an addendum Allied also has ones with presoldered tabs with 2 leg positive terminal: https://www.alliedelec.com/search/productdetail.aspx?SKU=70197007
haven't seen a lot of 3457a interiors, but the battery in mine has 2 legs on the positive tab, also makes it easy to identify +/- for us morons.

bronson · « **Reply #46 on:** January 31, 2014, 11:00:55 am »

Sorry to revive this old thread but @Fsck I'm surprised to hear your battery has two leg positive. My 3457a has the plain one-leggers.

Mine was made 3rd week of 1987, http://www.hpmuseum.org/collect.htm#numbers ). Is yours newer or older?

FWIW, this is what I ordered: http://www.mouser.com/Search/ProductDetail.aspx?R=BR-2/3AE5SPNvirtualkey65800000virtualkey658-BR-2/3AE5SPN

Also, is it really necessary to use a butane soldering iron? Seems like a typical grounded soldering iron would be fine as long as the multimeter is unplugged and a temporary battery is shunted in...?

AMR Labs · « **Reply #47 on:** March 04, 2019, 04:29:53 pm »

Hi BravoV,

I wanted to ask where did you purchase those gold color banana plugs that also allow wires to be connected to their end like that? Or at least, what are these called? Not sure they are the same used to connect speaker wires, maybe.

I realize this is an old post but knowing you are still very active on the forum on other threads, though I just ask here to keep this thread on topic. Not even sure how these are called, tried several possible names but so far was not able to get any meaningful results. Want to order a pair or two for my own 3478/3468 DMMs.

Thanks.

Quote from: BravoV on February 17, 2013, 06:02:47 am

My 3468A probably more than 20 years old and now about 3 years since I bought it, with with last cal stamp dated about 8 years ago and still very accurate, fyi last year I checked it against my friend's 34401A (annually cert-ed) and its still on spot according to it's spec.

Pics taken last year when I did measure low ohm resistor, and the resistor had been verified using 34401A.

BravoV · « **Reply #48 on:** March 06, 2019, 02:17:01 am »

Quote from: AMR Labs on March 04, 2019, 04:29:53 pm

Hi BravoV,

I wanted to ask where did you purchase those gold color banana plugs that also allow wires to be connected to their end like that? Or at least, what are these called? Not sure they are the same used to connect speaker wires, maybe.

I realize this is an old post but knowing you are still very active on the forum on other threads, though I just ask here to keep this thread on topic. Not even sure how these are called, tried several possible names but so far was not able to get any meaningful results. Want to order a pair or two for my own 3478/3468 DMMs.

Thanks.

Yes, you're right, its just ordinary banana plugs for audio amplifier/speaker wires, and mine are similar to these below, an example random result from googling "gold banana speaker".

Forgot where I bought it, maybe from local shop, usually those audiophoolery shop sell these, and they're quite cheap.

They're quite handy as test probes for thru hole components that have long legs, the top bolt can be opened quite wide, and can clamp quite securely on those DUT's legs, something like this below.

Also if you're lazy to find the like DMM test leads, or they're hiding some where, they're quite handy too.

AMR Labs · « **Reply #49 on:** March 06, 2019, 03:05:48 am »

Thanks for the info BravoV. Found these on ebay which I think are similar to yours:

https://www.ebay.com/itm/401033352392

Yes I agree they are very handy to test leaded components without using regular test leads, exactly why I wanted them. And also avoid the additional inductance and resistance.

Thanks again!


EEVblog Main Site	EEVblog on Youtube	EEVblog on Twitter	EEVblog on Facebook	EEVblog on Odysee

Author Topic: Quick question about HP 3468A (Read 25435 times)

Share me