Trying to identify components...

[Explorer]

In a nice old meter that doesn't work. The components are the 2 identical ones that are wrapped in brown tubes and have one set of leads twisted together. (2 photos attached.) Diodes? Fuses?

 

[Arouse1973]

Well I have seen a lot of components but I must admit I haven't a clue. They must be older than me Steve might know
Adam

 

[KrisBlueNZ]

Likewise, I've never seen those before. My guess would be fuses.

Have you measured them for resistance? Are there any markings on them?

 

[Arouse1973]

Likewise, I've never seen those before. My guess would be fuses.

Have you measured them for resistance? Are there any markings on them?

Dave might also know

 

[davenn]

LOL ... .I'm at a loss too

do as Kris asked, also do a little circuit tracing around them see what they are connected to/between

have you tried to google for a schematic of the meter ?

cheers
Dave

 

[dude]

They are germanium diodes.

 

[davenn]

They are germanium diodes.

really ? not like any diode I have ever seen but hey

got a link to something to confirm that for all of us to learn ?

Dave

 

[KrisBlueNZ]

Yeah I'm doubtful as well. The wires on them are very thick, and crimped, and I don't see any polarity indication. Where's the evidence that they're diodes?

 

[dude]

Here's some http://semiconductormuseum.com/MuseumLibrary/HistoryOfCrystalDiodesVolume1.pdf

 

[KrisBlueNZ]

Yep... Although I wouldn't normally trust any document written completely in MS Comic Sans, I have to admit that those components look very much like the second-to-rightmost one in this picture from page 13.



Apologies for doubting you, Mr. dude.

 

[davenn]

Here's some http://semiconductormuseum.com/MuseumLibrary/HistoryOfCrystalDiodesVolume1.pdf

cool article ... thanks lots ... yeah does look VERY similar to that one huh

Although I wouldn't normally trust any document written completely in MS Comic Sans

awwww Kris, I get so flaming bored with Arial or Times New Roman, I regularly write my www site pages in MS Comic Sans

Dave

 

[dude]

No problem Kris, its good to doubt.

 

[KrisBlueNZ]

awwww Kris, I get so flaming bored with Arial or Times New Roman, I regularly write my www site pages in MS Comic Sans

I think that's the problem - many people like it. So, people who obsess about that sort of thing (font nerds, I guess) associate it with mediocrity. The way I associate those title pages you see in old YouTube videos, that have blue backgrounds and moving text, with Windows Movie Maker.

 

[Arouse1973]

Here's some http://semiconductormuseum.com/MuseumLibrary/HistoryOfCrystalDiodesVolume1.pdf

Nice one Dude

 

[Explorer]

Thanks, guys! Thanks for the PDF and photo!

I can't find any info online on the device itself (e.g., schematic). Nothing comes up when I google the brand name " A and A" and multimeter.

I'll desolder the the diodes tomorrow and test them. There's one capacitor buried deep inside the thing. Does anyone know, if that cap has failed, would the whole meter be entirely nonresponsive?

 

[KJ6EAD]

That meter looks very much like some Triplett models.