Easy repair and teardown of the rather obscure Tektronix DMM916 Multimeter.
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#ElectronicsCreators #tektronix #Multimeter

Hi I'm just looking at a one of these tectronics DMM 916 true RMS multimeters that I got in my box of multimeters um that I had in my dungeon and I've got it set to a 3v reference source here and it's not quite 3 volts. but when I plugged it in, it was bang on 3 volts. Um and if I have a wiggle wiggle wiggle yeah, will it can I make it go back? Hang on it was it was working before. Come on, you can do it.

There you go. 3.02 it's oh 3.03 but you can see that it's bang on. So I think that we have a uh problem with the input jack? perhaps? um so yeah cuz like obviously like ADC reference everything else is uh is working for this bad boy. but uh, it's unfortunately like this is really high speec uh meter I haven't tried anything else yet.

This was the first thing I tried but it's yeah. look it's obviously working. it's bang on right 3 volts but it's a bit how you're doing. uh.

and the only other thing I found wrong with it was uh, this 9vt battery Focus you bastard There you go. Um yeah, that can happen to 9vt Batteries Not Just which have six 4 a cells in there. um not just to your doublea's and your Aaa's so beware. But fortunately it didn't really leak.

but uh yeah, the uh Magic Smoke escaped from that one and uh, physically ejected itself. so it's rather interesting. all right. So let's have a look inside this thing.

uh, this one doesn't have the Royal Australian Air Force on here like my other ones. I think this is the only one that doesn't. uh, have it cuz I Got a huge auction lot of these and this was Donkeys years ago I Got like a dozen of these meters um and I like fixed up and S you know, tested and sold the ones that worked and the ones that didn't work. um I left them in the or that were dodgy in some way.

I uh left them um in the box and this is this is one of them. So uh, unfortunately the tilting baale actually fell off one of the little plastic things. uh fell off. but um yeah, this is like a high-spec meter I don't know the specs off hand.

but uh yeah, if you got any knowledge of um who I mean I assume Tectronics manufacturer? Well no, maybe they didn't maybe they contracted out. but like it's a really high quality meter. But as you'll see inside, it's old school construction. Where's my bloody screwdriver? Yeah, there's no battery compartment in this thing.

so it really is like your old school like '90s even 80s style construction of a multimeter. And don't expect too many surface mount parts in here either. Um, and it's got some power on options. There you go.

disable a turn off be but test LCD segments gold. Oh nice. Anyway, let's try that, Shall we? Here we go There you go. test all the test all the segments.

This one's a bit uh scratched up but it is, uh, it is dual read out there dual display so tongue at the right angle. It's got a plastic clip at the top. It's not the best so don't not. the battery life on this is there you go.

Got some shielding, the piso and uh, there you go. No, they aren't corroded, they're actually. uh, well. they're a bit tarnished, but they've actually left the um solder mask off those for and that'd be guard.
um, trace for guard Trace Reasons I would suspect are they Anyway, that is. That is a definitely definite deliberate, um, leaving off of the solder M there. and as you can see, there's we got old school trimmers in here. There's our uh, hybrid resistor Network board to board, interconnect, um and another little carbon trimmer over there.

So that's probably for like oh, three more. three more carbon jobbies over there. Oh, we got some surface mount. There you go.

it's not all through hole a meter of this Advanced thing you're not going to. oh oh just it just lifts out. I've not taking apart one of these in ever since the original lot and the battery like there's no battery compartment like it's just. but.

then again, like your Fluke 87 has, you know, still got the wired 9volt battery. Hasn't it? There you go, We still got the uh, it's got. there's the LCD it's rather nice and there's the switch. Few switch afficionados that looks pretty decent should actually set that back to the N position of off before I forget and there you go.

So no wonder they make it easy to get out cuz the fuses are on the opposite side. There you go. They got the original uh little fuse jobbies in there. although that's a yeah yeah, that's a little fuse as well.

We got genuine little F little fuse fuses in there, two input fusible resistors over here that's like going to two separate paths and PTC encapsulated there with some heat shrink just in case the Magic Smoke escapes. You don't want it exploding everywhere, but uh yeah, you got the hybrid resistant. Network got another trimmer there and uh, That's All She Wrote diode Bridge protection ction should I take that apart completely. Oh, why not? Some people will probably get upset if I don't um, do I have to I've got to take the LCD No, no, I don't no no.

I just undo it from the back there I think that has to come off there and the others I can get from the top side here to get this board off. but uh yeah, leave it in the comments down below. If you know who actually manufactured this and did Tonics design it, don't know. Um, although Tectronics have acquired uh, various and of course you know, um, they were all acquired by uh, danur in the end weren't they fluke and all the rest of them and wave Tech and um, don't to washer flapping around in the breeze? All right.

So let's yeah, we got it. We got one. Oh standoff. there doesn't actually connect.

Oh wa no, it doesn't connect to anything. Anyway, is an NEC Jobby there you go NEC Fanboys Go wild. 78063 So that's doing all the um LCD uh driving. So presumably that's not the main processor.

So there's our range switch down there that looks in reasonable Nick doesn't it? Well, you know for the age I presume this thing is or you know that's still going to work. Yeah, don't have a problem with that n date of 97. There you go, 9717 and all right. So we have that processor and what have we got down in here I have to prop this up TC 8129 What's a TC 8129 I don't know but we got a 4069 over here.
4069 again T 62s all your favorites 4053 of course maxers more T g they fun of the T 62s got an 8737. that's the true RMS uh converter not seeing the reference. no no, don't see it anyway. Um, interestingly there's only this is a whoa.

this is a hello. That is who. So this is a two-sided This is a two-sided range switch. Double-sided range switch.

Now is this marked how do I get this back in right? Cuz we got the contacts we saw on the other side and then we've got all the contacts here so that's interesting. I'm not seeing any markings there, so hopefully I'm going going have to like R let the shaft will do that, but if you got it turned a bit in the wrong location, you're going to come a Guta That's interesting. Um, got an E Square prom up here. that's uh, calibration values.

Is this your reference over here that looks or is that just a regulator? MTS 102 No, that's just a transistor and it's got a Mbase collector there. So yeah, I don't know. Anyway, this isn't a detailed tear down I Want to actually haven't even looked at the solder the input Jacks yet? So let me just put this back together. So otherwise, um, I'll probably goof that range switch up.

From a production point of view, this really sucks. Really? No, it's not going to go in, it's slightly. oh no, no, there we go. Have: I Got in the right location that's AC that's DC Yep, Yep, Yep.

I got it. I got it the right way. Woohoo Win! Yeah, you can see how annoying this design. Oh, this design is just from a production point of view.

Please if you design the multimeter, don't do it like this and you got to, you know, take the entire board out to change your fuses and you know. eh? I Guess they hadn't. They didn't care too much back in those days, but these days it's bit inexcusable even. You know you can say it's inexcusable back then as well.

Oh well, let them off the hook. Just got myself an extra long pair of pliers like this for getting in places because I used to have one but it uh, it went Walkabout All right, let's get back to the input. Jacks and aha sorry, could have saved. you're all probably screaming at me.

um yeah, hello, um of course are they like Loosey Goosey I'm going to need a going to need a bigger boat I mean obviously if if you just got Shake proof washer like that, you could easily come a Guta oh yeah, well certainly wasn't tight and I yeah I can really can screw that up I really don't like those but they are nonetheless like often. yeah I suspect like because we're talking like 10 megga ohm input impedance there and we will getting the uh, we'll getting readings like slightly low and stuff so I can only presume that like it was just a really high impedance path there and that was causing causing a problem and you probably would have seen that on Ohms if I bothered to test that. but uh yeah I don't know. Maybe I could unscrew it and clean it and stuff like that, but I'm just going to put that back together.
Is it that easy? Could be Yeah Bang on uh, 29996 volts. Uh, for three volts, this isn't my best uh reference. This is uh and if I Wiggle Wiggle the Jack Wiggle Wiggle Wiggle Yeah n it's all good. There you go, you can see that 2.99 96 and that's good enough for Australia And there's no wiggle.

Oh no. 29999 Now Oh yeah. Yep. So there you go.

Nice! AC Plus DC Let's take it back to three. 3.08 for 3 volts. Yeah, it's all looking good. Let's see if those fuses are intact and we can measure current.

Probe Probe Probe Probe Yeah3 m milliamps. Uh, turn it to microamps 299.99 microamps so no worries I Can only go to 30 milliamps maximum but it's intact. There you go. 30 So that is a winner.

Winner Chicken Dinner Probe Probe Probe: There you go. Um so that is a real easy. It's not even a repair. Um well I guess it is right.

It was just a dodgy input jack, but it's very curious that uh, you know it had a rather than just give no reading at all, it gave a high enough impedance that it was given a voltage divider with the 10 mega ohm input nominal 10 or 11 or whatever. Uh Mega input impedance of this meter. Um, and so yeah, it just like uh PL maybe some tarnishing on the contacts and combine with the looseness of them and just tighten them up and it p through pieces through any oxidization tarnishing on the contacts and it's a winner. So yeah, there you go.

Um, the Tectronics DMM at 916 multimeter I wonder if the others are the same that would cuz I've got three of these. Um so yeah, it's a uh I have to check the specs on it. but I do believe like it's a pretty high end. it's like I think it's 30.

It seems to be like 30,000 count so it's uh, you know it's your 4 and 1 half digity. Plus let's get my 10K reference here. see if the Oh SK is good I'd be surprised if the Oh Skar is bad because you know the meter works. It works 9991.

Yeah, it's a little bit. it's a little bit lowish 993 but I'm pretty sure that' be within spec, right? No worries, What is? You know this? Surely this would be a 0.005% class instrument. although you wouldn't that's DC volts. You wouldn't get that on your Ohms range.

That is a simple repair. Hands up if you have one of these. Uhuh, if we look down here made in Taiwan Who in one? So it's one of the Taiwanese manufacturers. maybe they designed it as well.

Um I don't know is an early. it's I don't know. Did Briman have a hand in it back in the early days Briman were making meters? uh back then. but uh yeah, leave it in the comments down below.
if you know who actually manufactured the Tetronics series multimeters, but there you go. Repaired Beautiful. I'll screw that back together and Bob's your uncle. Maybe this is this sort of stuff's annoying I know, no, that'll just yeah.

I can clean that off? That'll it'll clean up nicely. Shame About the scratches on the screen and stuff that's not a is that silk screen underneath. If it is, then you could get medieval on it. Um, and maybe you know, buff out that window and a fine multimeter.

How's the continuity tester on it? Oh, that's A. it's loud, it's instant. And how's the auto ranging? Ready set? Oh Ready set Go well. not bad and it's got like a um 30 ohm range as well.

Brilliant. or is that 300 sorry, that would be your 300 ohm and 10 mli ohms Resolution: nice and you know it's got all sorts of fancy stuff. like it's got, you know setup I don't know, right? And it's got all sorts of fancy whizbang stuff. and you can store.

you can. actually? well, if we get an exit set up, if we actually we can change the number of digits. There you go. It's got Auto hold.

So it's got a fluke auto holdy type thing. What does gold mean? Oh gold. I Was wondering what gold meant. It's the gold color.

here. It's invert so it's gold. Took me an embarrassing amount of time to figure out what the heck gold meant. Um, so the auto hold does it? Yeah yeah yeah.

it's got the fluke style Auto hold thing, touch hold. so yeah yeah, it's a fairly capable uh meter store. Recall: what else do we have in the setup? Can we go side to side? no and bar graph. oh that what? It's got different mode bar graphs.

Does it have like Center zero? and stuff like that probably does. So yeah, it's got the Dbms and we've got temperature as well and it's a pretty capable little thing. Didn't measure the nanofarads there you got? It's got 300 residual puff that is. Oh I'll tell you what.

I will leave a link down below to my EV blog eBay store and I will auction this off are starting at 99. So yeah, if you want it, go for it. I'm sure it'll uh serve you well. Anyway, there you go.

If got any details on the tectronics DMM 916, leave it down below last calibrated in 200 10. That's still a winin' meter. Anyway, if you like that video, please give it a big thumbs up. leave it in the comments down below.

If you um, know about the history of the DMM 916 or if you're still using them or you're used to use them, catch you next time.

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29 thoughts on “Eevblog 1576 – tektronix dmm916 multimeter teardown easy repair”
  1. Avataaar/Circle Created with python_avatars q zorn says:

    That poor Tektronix DMM916… Some people treat expensive test equipment like a football. 😎 Thank you for the great video. 🥳

  2. Avataaar/Circle Created with python_avatars Trevor O. says:

    It's about the time for multimeters to have LCR function, that is, internal signal generator and logging, which is not really difficult to make. Yet those expensive ones don't have it, while it is supposed to be a MULTIMETER. Along with high-resolution full color LCD and USB charging.

  3. Avataaar/Circle Created with python_avatars John USP says:

    Bought one for $25 😉

  4. Avataaar/Circle Created with python_avatars Vbe says:

    Very nice meter and video Dave!

  5. Avataaar/Circle Created with python_avatars Gautam Damodaran says:

    I think it's made by Escort.

  6. Avataaar/Circle Created with python_avatars Mike S says:

    Nice dmm!

  7. Avataaar/Circle Created with python_avatars Frank Pitochelli says:

    Dave, the camera work was a bit dodgy 😅….
    Best wishes pal…
    Enjoy the channel.

  8. Avataaar/Circle Created with python_avatars Yuzu Ryougi says:

    Where is my bloody screwdriver?!

  9. Avataaar/Circle Created with python_avatars Gordon Wedman says:

    I have two of these. Nice meters. Your will not get one on eBay for 99 cents.

  10. Avataaar/Circle Created with python_avatars Hendrik Hanssons says:

    DuraLeak at it again.

  11. Avataaar/Circle Created with python_avatars Simon Crabb says:

    PP3 batteries don't contain AAAA cells, they're a few mm shorter. Urban myth!

  12. Avataaar/Circle Created with python_avatars Gherghinescu George says:

    Tektronix DMM252 is an APPA 105. This DMM916 looks like a modified but related model inside. Credit to retiredcaps and mr.modemhead who wrote about them on EEVblog forum.

  13. Avataaar/Circle Created with python_avatars Udhaya kumar A says:

    What's special about multimeter fuses. Why it's odd size and pricey 😢

  14. Avataaar/Circle Created with python_avatars schitlipz says:

    I had to sit through two full ads for this? Thanks Dave.

  15. Avataaar/Circle Created with python_avatars Budi Suryadinata says:

    That looks like being made by APPA taiwan, it even has APPA logo being silk screened on the pcb.

  16. Avataaar/Circle Created with python_avatars Wiwing Margahayu says:

    iron and airplane is amazing Sir

  17. Avataaar/Circle Created with python_avatars ksio89 says:

    Duracell and its patented "Duraleak" technology😂. While I don't use Duracell alkaleaks anymore, I still don't leave them inside my DMM, but wrapped inside a plastic bag in case it leaks. Anyway, great work David.

  18. Avataaar/Circle Created with python_avatars Chris Grossman says:

    May be GW Instek. Tek and now Keithley rebadge GW Instek products.

  19. Avataaar/Circle Created with python_avatars Maks pesic says:

    Pozdrav za kralja 👑multimeter❤👍🏻

  20. Avataaar/Circle Created with python_avatars Richard Fraser says:

    That one has been around the block a few times.

  21. Avataaar/Circle Created with python_avatars Artichoke4Head says:

    that naked trace is gold-plated and I don't know why they did that!

  22. Avataaar/Circle Created with python_avatars Ron says:

    given its age and while i was in there i'd probably have just given all the contact points and banana holes a squirt with some contact cleaner/deoxit just to get it nice and fresh – fun to see the old meters still tanking along though! my cheap one failed dead short after 6 months!

  23. Avataaar/Circle Created with python_avatars Jeff Dutky says:

    I bought two of these off eBay a couple years ago, and probably paid way too much for them, just because I love the auto-hold feature so much. I wish that more DMMs offered auto-hold, rather than the normal hold feature where you have to press a button to get it to hold the value, because I never have a hand free to do that when I need it.

  24. Avataaar/Circle Created with python_avatars molasses says:

    I love the style of these old meter designs, personally. The Brymen 85x and Fluke 87 series come to mind. If only they could make meters in this style with the modern amenities – AA battery compartment, fuse access, etc. The plain rectangular chassis just looks nice and professional to me.

  25. Avataaar/Circle Created with python_avatars Feuerbard says:

    inside look like wavetek

  26. Avataaar/Circle Created with python_avatars IanScottJohnston says:

    Nice feature rich DMM. Would adorn any workbench with pride!

  27. Avataaar/Circle Created with python_avatars Malcolm Swart says:

    Multimeter construction screams Brymen to me… even the shape of the plastic case, the rotary switch, and the soft buttons look like my brymen meter I have at home

  28. Avataaar/Circle Created with python_avatars ReeDreamer says:

    I always love a good multi-meter tear down. ; )

  29. Avataaar/Circle Created with python_avatars Justin Richards says:

    battery still connected. Could not help myself from commenting

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