help oldish multimeter

[robert the violinist]

Hi, my cheapy multimeter stopped working so i found an old one that id packed away years ago. An Altai kd-30c.  I believe i bought it in around early 1980`s.Im not too up on electronics but hoping someone could tell me whats likely to be wrong with it ?? In simple words, apart from throw in bin.
I tested it on a 9v battery for dc volts and it gave 6V DC ! But when i try and read a 8 ohm resister which i know reads 8.3 ohms on my other one which broke, but this just goes up and down in value on the digital display in a constant cycle.
Ive had a look inside . Slightly corrosion on one battery terminal but inside theres a bulb which is soldered into the circuit and it looks like it has possibly a broken filiment ,also the  piece at the botton a sort of row of spiral wire doesnt look too good and a black lead on it appears to have melted a bit or something.
Any help appreciated .
Thanks Bob

[ppppenguin]

I know we at GVR are dedicated to rescuing old kit but on this occasion I suggest it's bin time. There are loads of multimeters available for nominal prices. I've no idea which are recommended these days but here's one example: https://www.screwfix.com/p/lap-mas830b-d...600v/75337

Or for a bit more money something like this: https://www.amazon.co.uk/gp/product/B075...tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=B075L7PQ3Y&linkCode=as2&tag=topchoseo-21

Not sure I believe the Cat IV rating I can see in the photo.

[robert the violinist]

Hi Thanks , i thought that may be the answer, thought it might have been something simple as i dont particulrly like throwing things away.
Bob
p.s do all new multimeters have sheathed banana plugs now ??  can you get adapters to plug an unsheathed banana plug into in order to plug into a modern meter???
A photo may explain better , i need this probe to plug into a newer multimeter ,the probe has unshrouded banana plugs.The skytronic multimeter is the one thats broke as well but newer ones all have shrouded input sockets. You can see how recessed the skytronic sockets were ,too deep for the unshrouded banana plug, are they al like that?

[ppppenguin]

I've had a look at a couple of my multimeters. One is an old Fluke 87, the other a new-ish cheapie. Both are designed for shrouded plugs, both happily accept ordinary 4mm plugs. The picture of the Screwfix one I suggested looks like it will take ordinary plugs.

I really don't think it's worth salvaging what was a cheap and cheerful meter in the first place. I know it's not nice to chuck stuff but I'd regard those as completely disposable. I bought a Fluke 87 many years ago. It cost a lot but I still have it and it's still working nicely. It predates the Cat safety scheme but I'm happy to use it on mains.

On the other hand a few cheap DMMs are always useful when working on some types of kit and you need to look at several things at once.

[robert the violinist]

thanks for the reply. I actually bought one the other day which i havent received yet an Extech ex-430, used but in little used condition for £30 with shipping. I hope it will take the unshrouded banana plugs and the recessed sockets arent so deep.
Bob

[Terry]

Our very own Mark Hennessey has written a lot about cheap, but good, DMMs.

You may be interested in his comments.

See https://golbornevintageradio.co.uk/forum...p?tid=5501 and you'll see what I mean.

[Refugee]

When Mark did his reviews I bought a couple and found that one of the better suppliers was banggood.com.
They offer competitive prices and send out far less unwanted emails than many others.

[Old Sparky]

On a related topic, does anyone make or import a decent analogue multimeter these days? I have a Russian U4324 which needs a mod. doing in order to fit the nearest available battery, and a small Di-LOG bought from CPC years ago, but another decent analogue meter wouldn't come amiss.

[robert the violinist]

Our very own Mark Hennessey has written a lot about cheap, but good, DMMs.

You may be interested in his comments.

See https://golbornevintageradio.co.uk/forum...p?tid=5501 and you'll see what I mean.

Thanks Terry , very good detailed reviews of the various models.
Today i just unscrewed and unsoldered that bulb on the circuit board and then screwed back in and resoldered and now got this in photo(50w 8ohm resistor) , no more erratic display.  The bulb hasnt a broken filiament but one has came off the little hooks inside whatever they are called.

[Terry]

I think they're called 'little hooks for hanging things on', Bob.

Did you think to look for any markings on the base of the bulb while you had it out, in case you need to find a replacement in the future?

It may be a thermistor (or a bulb being used as a thermistor) but why, I have no idea.