I accidentally shocked my DMM, any ideas on fixing it?

[ErnieHorning]

The MOV, if you get that far, is 820KD07.

The data-sheet can be had from here look for 70mm devices on page 12.
http://www.electro-tech-online.com/c...ies_5_40mm.pdf

[tfischer]

If you do end up replacing it (which I think is probably where you'll end up), check out this one - probably the best bang for the buck out there:

http://www.circuitspecialists.com/csims8264.html

I got one of these for free when I bought my soldering station. I wasn't expecting much, but wow - in some ways it is nicer than my "main" meter. This one has backlight, temperature probe, capacitance check, etc. etc as well as the standard functions.

For < $30 it's a no-brainer IMHO.

[dirknerkle]

If you do end up replacing it (which I think is probably where you'll end up), check out this one - probably the best bang for the buck out there:

http://www.circuitspecialists.com/csims8264.html

I got one of these for free when I bought my soldering station. I wasn't expecting much, but wow - in some ways it is nicer than my "main" meter. This one has backlight, temperature probe, capacitance check, etc. etc as well as the standard functions.

For < $30 it's a no-brainer IMHO.

+1. I got mine free with a soldering station too, and it's quite a powerful DVM.

[ErnieHorning]

I got both of mine free from work, right place, right time.

First one, an old Beckman, was one of two that didn't have a beep function in ohms and everybody hated it. We scrapped them so I took one home. Then missing beep has never been an issue. The battery lasts for months, even if I accidentally left it on.

The second one, a Fluke that had been stored in a cabinet for 10 years and had been written off as being lost a few years earlier. So I was told, "here, it's freebie".

There's plenty of cheap one's around that have a lot of cool features. Some arn't needed much but are pretty handy at times.

[carlk]

The fade of the LCD looks like a slow voltage drop.
You should probably get the pinouts of the three chips and check for the correct voltage(s) when turned on.
If the meter had a 500 Volt range I would use a 600 Volt MOV to replace it.
Sears may have a replacement PCB, which would be cheaper than buying a new meter.
Hope you get it working,
Carl

[ErnieHorning]

Sears may have a replacement PCB, which would be cheaper than buying a new meter.

How much cheaper could it be? They're on sale for $19.54 and you can save on shipping by sending it to a store.

BTW, I talked to the company instrument tech and he said he tosses them if the MOV is blown. They're so cheap now that it just ain't worth the hassle.

[CaptKirk]

+1 on that price. I bet if you try to get a replacement board, they charge you double or triple that because they have to spend the time to buy one at full retail and then strip the board out to send to you...

[Jrd]

It looks like the LCD driver is blown. A normal LCD will act that way when it loses power, signal, or is getting the wrong frequency signal. Without a schematic, it will be difficult to figure what is the LCD driver chip, but I think you should take it off life support and let it expire gracefully... ;-)

I am sorry for your loss... our prayers are with your family.

Well, the LCD driver is probably this big 40 pin IC hiding under the LCD:

The MOV, if you get that far, is 820KD07.

The data-sheet can be had from here look for 70mm devices on page 12.
http://www.electro-tech-online.com/c...ies_5_40mm.pdf

Thanks! I can't seem to find that number at Mouser. Do you know where I could source it from?

If you do end up replacing it (which I think is probably where you'll end up), check out this one - probably the best bang for the buck out there:

http://www.circuitspecialists.com/csims8264.html

I got one of these for free when I bought my soldering station. I wasn't expecting much, but wow - in some ways it is nicer than my "main" meter. This one has backlight, temperature probe, capacitance check, etc. etc as well as the standard functions.

For < $30 it's a no-brainer IMHO.

I have had my eyes on that one for a while now and while this is a (very) good excuse to get it I was planning on getting it(free) with a new soldering station and I am not sure if there will be enough left in the budget yet or not.

The fade of the LCD looks like a slow voltage drop.
You should probably get the pinouts of the three chips and check for the correct voltage(s) when turned on.
If the meter had a 500 Volt range I would use a 600 Volt MOV to replace it.
Sears may have a replacement PCB, which would be cheaper than buying a new meter.
Hope you get it working,
Carl

Good idea, the four ICs in the photo above from bottom to top to right are:
Bottom 16 pin: CD74HC4538E H9806BBJK
Middle 8 pin: 062D JRC 8052B
Top 14 pin: PHILIPS HEF4011BP B86850PS Hmn9827 4
Right 40 pin: ICL7106CPL H9740
I'll try to find the datasheets tomorrow night after I get home.

Yes, the meter has both AC and DC 500V settings, you can see them printed on the silkscreen of the PCB in the bottom left hand corner of the above picture. Could you please suggest a 600V MOV? Preferably with a source?

I don't know about getting a new PCB with components cheaper than a whole new meter.

How much cheaper could it be? They're on sale for $19.54 and you can save on shipping by sending it to a store.

BTW, I talked to the company instrument tech and he said he tosses them if the MOV is blown. They're so cheap now that it just ain't worth the hassle.

Where is that link supposed to go?

I know they are pretty cheap, but I like to fix things if I can, especially when I break them like this.


Thanks for all the input guys! The Christmas lighting hobby without a doubt has the best group of people out of any other hobby I've looked in to!

[ErnieHorning]

Where is that link supposed to go?

DIYC locked out my IP at home so I didn't see this last night. I wish there was a way to fix that.

Hmmm... the link worked when I posted it. The link is at sears.com though it looks like the price changes. Right now its $20.69.

http://www.sears.com/craftsman-multi...p-03482141000P

[rstehle]

I realize that price is a consideration, but wouldn't an auto-ranging DMM provide more protection from over voltage situations? You might try eBay..........