Hi welcome to tear down Tuesday Haven't got around to this one for quite some time. You may remember this bit of old school test equipment porn from a auction school which I got which I'll link in that down below and it looks pretty harmless enough, but Tada, look at that. Oh, just beautiful. And what we've got here is an Evo 1962 vintage.

Yes, 62 that was even before I was born. Goodness, it must be old. CT Double for Six Transistor tester is the model number on this thing. Serial number 806 So yeah, probably was the eight hundred and sixth one made in the old dart of course.

Hotter war my pommy viewers I don't know what does Zed for Zed da etc stands for. But anyway, definitely Serial number Armed 806 made in there. We got 1962 and that is definitely the model number that's been confirmed. CT Four Four Six There is a Mark Two version of this I believe but this is the original and it's just beautiful.

Look at all those knobs and this one is in absolutely superb condition. It looks like it's had very little use at all and it's all got the original look at this. It's got just the rubber bottoms on the thing, nice attention to detail. It's got a carry handle and of course the latches.

And consider when it comes from 1962, I Mean there's no rust or corrosion on the thing. really? haven't had a look inside yet, but geez, you know we don't I expect it to be just as good as the outside. It's just brilliant. And the quality of the knobs on this thing just are really.

you have to, you know I wish there was feel over vision I Really do because this is just stunning. The wire round pots listen to that. Ah, beautiful wire way on pots and just nice big ball bearing switches on the things. just absolutely beautiful.

And the analog meter? awesome. And that's individually. Check it out. Individually hand numbered.

so maybe they hand tested these things. Even the meter has its own serial number. Look at that. Ah, it just reeks of robustness.

Look at these. Kerry Hat not only sort of like carry handles, but designed to protect the input and output. Banana or input. I Think that both the inputs.

Anyway, banana plugs here and oh, it's just fantastic. Looks like this lifts out. I Believe this is like the battery compartment for the thing because hey, it must have batteries to actually operate. But yeah, it's a transistor.

test that it tests transistors or it's a transistor analyzer. sorry. and this one was supplied by the Australian Agents Electrical Equipment of Australia Limited in Liverpool Street in Sydney I Wonder if they still exist in some way, shape or form? I Doubt it. Look at this beater and noise control dial.

This actually might have a bit of an issue because it does go past there and seems to go more than one rotation. So I think and it does slip occasionally so there could be potentially something a bit askew with that. But jeez that, it just feels beautiful and it's just awesome. Build quality on this thing.

Remarkable. No wonder it's lasted all this time. now. The only thing you might think so bit Dicky are these our input connectors for the transistor itself.

Well they're not designed for transistors to plug directly in. that's why in the top of the case it comes with our this test lead. there it is gonna collect the base emitter and that just plugs in I could just yeah and then they screw in like that and that's just beautiful. It is absolutely stunning and I've got a cable on it with just some dodgy you know it was obviously designed for whatever as some sort of thing to plug in.

it's got the original wonder if they're 1960s vintage collector base emitter. There you go so no color coding or anything. think I might real able those I Really like this main function switch here. look at this.

it's got big on there so this is actually so it's off at the moment and Sivan got on on the other side like that as well. So you can see it on there. this. when you've got it down on the bench and you're just looking down at an angle like this, you can actually see it.

So they've thought of like thought of everything there. It's just brilliant. So that's dou Y that's to switch the thing on in meter mode and then you've got all the different no It can do our noise measurement as well and all sorts of bits. Everything but the kitchen sink.

So we've got our input jacks for our NPN and PNP transistors. You have to test them separately and then you can set the collector voltage here anywhere from 1.5 volts up to 10 point 5 volts. That's for the internal. have a look at the batteries when we open the thing up or you can I switch it through to an external voltage here.

12 volts max or up to 150 volts maximum so you can test. You know, reasonably high voltage transistors, although a pretty high voltage for the day Anyway, you've got to remember to back in the 1960s, I mean every most things would discrete art transistors. Well, transistors were just are. Some things were still valve and that transistors were just are coming into vogue and ICS were extremely limited back then.

So transistors were the Ducks guts and the new technology coming out. And you needed these analyzers and transistor testers because transistors they hadn't, you know, perfected the fabrication techniques we take for granted these days. and all the huge you know fantastic specifications you can get these days. But even when they made this, they still had thousands of different transistors on the market.

and and they'd have leakage and problems. And they'd have all sorts of you know, processed technology problems. And it was really important to actually individually test and characterize transistors to make sure that they actually worked. and if they blew.

Hey, your test and replace the transistor and you'd find and you'll be able to use something like this to test if a replacement. Transit There was a suitable substitute for the ones you're doing in in terms of beador leakage, noise for example, which they got down here. You know, all big, all the big deals, and just like any regular multimeter, this scale is going to be multi range depending on how you set with the meter switch here. so 0 to 1 milliamp for example.

it might have a hundred milliamps on the scale, but that would be a hundred micro amps full scale for example. and then you can just dial in that it does current and also voltage as well over here. so dual use voltage and current. Mirrored scale on that looks like a really nice meter.

It's not mirror back to eliminate parallax error, but high G's it. just it just looks and feels good quality. I mean check this out. They've even gone to the effort to put a rubber seal around that meter on there.

You know this is probably designed to be, you know, splash proof or something like that. You know, sort of weather resistant kind of thing. Sort of like a really yeah, I kind of like a military-grade kind of build on the thing with the case and everything else. So you can see up here that we can set our base current course like this.

So the dual ranges one to 40 milliamps and zero to one milliamp. So you know if you've got a bigger power transistor with very low gain of like 10 for example, you know you'd whack it right up here on the Wunder 40 milliamps and then you've got the course you could go I Mean it's got a thousand on there, so that would be like a four. that would be like 40 milliamps full-scale base. and there you can it with your tongue at the right angle? just tweak it with your fine control here.

But that's just beautiful. And it's got two meter output. So with HP and LP I don't know, Haven't read the manual in detail. I'll link in the manual down below.

Actually, it's got the full operational aspects of this and the schematic as well. I Know what you're saying? Enough talk. Dave You want to see inside this beauty? And by the way, yes, Ah, smells as good as it looks. It really does that old fashioned bakelite smell.

Hmm, ah, sniff that order. It's probably bad for me cancerous, but geez. I Love it. So here we go.

let's lift out this which is the not. It's a weird combination of the collector voltage controlling us. they didn't have enough. you know, space elsewhere on the box to do it.

so they've had to combine it with thee. Let's have a look. Tada battery compartment. Check that out.

We've got these connectors here. There's one here and one on the other side. Look at that. I mean there's nothing to hold that in? I'm a bit disappointed and surprised by that vibration.

Could you know shock or vibration could make that fall out? Maybe there is a way to hold it in, but it doesn't look like it. and there's a another one over here. So basically that's just taking all the controls there from the top. And ah, I've released all the smell too, by the way.

Mmm. fantastic. And you're wondering what these things are. Well, they're the.

yep, they just pop off. So these are a U10 battery which was um, and Eveready yard type which was quite common back in or AVO and old-school teske like this I think they're also known as R12 and I obviously don't have many, but look how many we've got. Two, four, six, eight, ten, twelve, fourteen batteries. and yes, they're just like a zit though.

or like a zinc carbon. 1.5 volts per pop. So they've got a big spring in the base of that and a contact down in there, which the contacts look in fantastic condition considering that they're over over 50 years old. I Mean jeez, you know, like this is just absolutely remarkable.

The longevity of this thing? absolutely stunning. Obviously it's been stored in a you know, a really good location, but yet these would all be in series. I'm not sure if they're tapping it off elsewhere to get a smaller voltage. I'm not sure but yeah.

I mean I could probably whack a a double-a in there or something and see if it goes in and makes contact. And of course, as you'd expect, the quality of the custom gained switch in there is looks like they got jewel wipe contacts in there as you'd expect. looks very nice. I Got nice ball bearings in there.

look at how that very nicely are tied in all the just bundled the wires there. the wire looms with just this I think it's a just wire? I think yeah, that's just like beautifully done look at that. it's just gorgeous. Man, somebody really took pride in that.

You can also see all the other wiring down in there once again, all learned and cable-tied like every centimeter. That's just. that's just beautiful. It really is.

and this is just that. this is just the top. Imagine what we're going to see inside so we'll just whip this top off. It looks like it's all just going to lift out and it's got looks like these screws around the outside here.

and of course Phillips that's not going to work. And I expect metal threaded inserts. None of this screw into plastic rubbish. Yep, look at that.

Even got washers. Brilliant All right. I Like Boyer All right here we go. Let's lift the skirt on this baby.

and actually I might do it this direction. Oh yeah, I got them all. Yep, yep, look at that Tada that's clean, beautiful, and oh yeah, oh that looks really stunning. Look at the lumen on that beautiful our precision resistors here.

We'll have a closer look shortly, but that looks in like as new condition. Wow Now as you can see, it's all pretty much our turret board and point-to-point construction down in here. like there is nothing on the back of those. If you're wondering, there is.

You know it's not a printed circuit board. it's just the turrets through there. and then the individual individual resistors and caps with their legs just wrapped around those our turret pins and soldered. But just look at the neatness of the of the wiring and all that looming that is just gorgeous.

Please caps, look at that is that. Yeah, Five hundred, five hundred. Mike There we go. Beautiful.

Ah, made in the old dirt as well and made in the old diet. Doesn't stop there either. Look at this thing I believe that's from my Mahad absolutely fantastic classic name and I believe that looks like an inductor that looks like a big-ass inductor. or maybe a trans No maybe a transformer.

Actually, it's got two sides there didn't see that one on the other side. So yeah, that's most likely a transformer. I Should dig out the schematic and have a look. So if we do have a squiz at the schematic here, link provided down below just on that top board there with the battery.

Yeah, I was right. Look, they've got some, like a couple of our cells in series down here and these ones here all tapped off to that collector voltage. Our range switch that we saw on the front panel here we go here is the main schematic and there's not much to it. There's lots of switching porn around here.

of course, how they design these things. That's just. you need to keep all this in your head and figure out how everything switches. It's just.

you know, a lot of the high-end multimeters and things like that. Just remarkable. Anyway, so lots of switching around here. No.

I should look closer. This Mullard thing is an inductor. It's only look. It's only a single contact, one side and single contact the other down in there.

So it's not actually the transformer, just the inductor. That's it. So that's definitely not the transformer here. for our one Kilohertz oscillator.

the only other inductor I can find over here is this one all on its lonesome, which goes all the way back over to here, which is, uh, presumably our phase splitter. I Haven't analyzed that or thought about it, but that's the only major component in here. so it's got to be that inductor down there in these little suckers which I thought were inductors at first. they're actually wound bobbin resistors.

so I think ones are point three ohms and ones about three ohms. So that's the yeah, they just didn't have them in these sort of packages like that. These are one percent resistors I believe. but you know as your axial ones as you're familiar with.

But to get the low value resistance as well, they had to have a my wound on a little bobbin like that. Check this out. Is that some sort of body or what look they've got that wire soldered onto onto there? they getting a little bit extra resistance out of that or just flapping around in the breeze? It just seems a bit out of character. And by the way, my humble apologies, these are not capacitors.

They're condensers. They didn't call them capacitors back in the day. Bloody condensers. Thank you very much And check out.

those hand-written Welwyn resistors that we've seen before on the blog are just beautiful or handwritten and we have ourselves a little coax there that runs around to the front. that's the oscillator output by the way. and that runs down to this separate board here. So Bingo! I Think we have found our oscillator.

Our transformer is inside there. Oh man, look look at the size of this thing. It's just enormous. Is that a little tremor on top as well? Wow that's our one Kilohertz oscillator.

Oh, so if we have a look at our oscillator circuit here and it's a dead giveaway because there it is. screen. So it's all. all that circuitry is screened.

you know, Massive high-frequency One Kilohertz Sine Wave generator. Got a screen. the sucker and you might be going. Well, where's the transistors? Didn't see any on the board? Well, tada, lift the top lid on that and there you go.

I Mean this is the this is the control. - of course there we go. That's our, that's our main feeder and noise. there are in sisters.

look at those. Bingo. they're armed I Believe a they're either a Maillard OC 75 according to the manual and schematic and parts list. Very comprehensive parts list in this thing list.

every screw and not a knob and cable tie and everything. It's absolutely incredible. or a CV 2400 I Don't know what a CV 2400 is, but yeah there. L There are transistors and there's the three leads coming out.

They've got two insulated ones, they've put a insulating nuts sleeve over that I don't think that's are embedded into the actual transistor itself. and then we've got a better lead coming out. Just all point-to-point stuff so that they're our two transistors down in there. Oh no, oh, this is just ruined it.

Look, we have one. Lee Keep Lizzie Cap bloody please. Caps I'm not sure what that one is, but this one's our pleasure. and it's leaking.

Ah bummer, there's the culprit. Plaisir Right down in there only lasted like 52 years. Dodgy has got some more big-ass resistors there by the looks of it on these range switches and it looks messy. but that you know there's just the way they've are tied everything together is really very very nice and my hat's off to them.

I Mean that is just you know. really professional looming. it really is. And if you're wondering what these are, these are the push-button switches.

I'm putting my finger on the bottom there and you can see the slider. Go there. The contacts are actually there's no contacts on this side down here, but the contacts are over on this side. I'll see if I can get a different angle and yeah, there we.

There's still none on that side. Oops. But yeah, these are the beautiful little push button. not little, a huge push button switches with the cutouts at the slot cutouts in the board for the wait for contacts and the turret studs.

Just beautiful. Yeah, there we go. There's only one contact in that you can see it. right up the back there.

there's a there's not many contacts on that set. On that particular sucker, there's more on the other one. So there you go. you can see the dual wipes on those are by dual wipe I mean top and bottom.

In fact, their triple wipe. They got two contacts on the top surface and one contact on the lower surface. and these I can bet your bottom dollar. These contacts are still reliable after 52 years and there's a mod record plate as well.

Nice attention to detail. So if they've modified this thing after it was assembled or maybe even now at the factory at might you know the new products coming out might have a certain mod status. They've improved the design or whatever. it'll be marked on there but looks like hasn't been touched.

They got it right the first time these people knew what they were doing. These are our wire round potentiometers of course, our dual ganged here so they've got the top one and the bottom one. They're two separate ones on the same shaft and that's just beautiful. You can just feel the feel the precision wire wellness in there.

is that a word? It is. Now there we go. Deep down in there I won't like take the whole thing apart and be really messy, but got ourselves another transistor down in there I think there's five transistors total. Yep on this entire thing.

Ironically, a transistor analyzer needs some transistors. We've got ourselves a Germanium our point contact our Diode down there. absolutely bet your bottom dollar at side Germanium, another transistor down in there, and just some more our point-to-point stuff on that on that vertical board in there and that'd be part of our phase splitter or our circuit. You'll notice this cycle round connecting point down in here.

It's got just got multiple contacts on there so they can wire everything down to a central our star point: I mean this thing's I've been working at one. Killer. It's but you know, look. star grounded down to the metal case down in here.

Brilliant. And by the way, all the cabling are going over to our main top transistor input board here. this is all shielded so you can see the shield down in there going down to our main star grounding point. There, there's the ball bearing on our rotary switch there.

That's why it feels so wonderful. I Love a good set of balls and I find the tie-down straps on this please'. Capacity's guy capacitors here. Absolutely wonderful.

They're a rubber they're designed to pull off. They're really quite hard, but I think it's saying made in? England they're even the rubber tie-downs A bloody wall made in England Ah, fantastic sir. anything in here there's not made in England And what on earth are they? Look at? these little free wired like little flying saucer discs? Things: I've never seen those before. It's got one hour to E1 on it.

Um, it's almost as if it's some sort of, you know, plate A? You know, low, low valuer plate. air condenser not not capacitor. Um, but one r2 I Yeah, I Don't know. That's very interesting.

Let's have a quick measure of that. I'm just a You know, using some dagi leads here, so please excuse the crudity of this measurement and it's definitely not resistor. There we go. Seven hundred and thirty-odd puffs furrow that sucker and the other one.

Yeah, there we go. Yep, they're little, some sort of, you know, ceramic type plate condensers so that is just gorgeous old school. I Hope you enjoyed that as much as I did in glorious hour. 50 frames per second? Hopefully this is just.

it's beautiful really that make them like this anymore. Just the the point-to-point wire in the tag board construction. classic 1960s and big. SR condensers with the big straps on those weird-ass a little ceramic or whatever are smaller value ones.

The you know, the hand wound resistors here for the smaller values. just the hand numbered. the hand labeled resistors over here. Just beautiful.

The oscillator over one Kilohertz oscillator in its own case over shielded case over here. Ah, it's just a thing of beauty and a joy forever. It really is. Oh, and by the way, yes, this is all rubber surround in there, so obviously designed to be like, you know, at least our splash proof.

something like that. Just fantastic build quality. And it turns out that a double-a battery might fit in there, but in terms of I getting a contact on the top, it's going to be tricking I Don't actually have that many double A's to hand here in the lab to power this thing up. So yeah, I want to get this video out today so unfortunately our we're not going to see it working.

but if you want to I can always do a second video on having a play around with things this thing. this was only supposed to be a teardown. but yeah, if you want to see a video and I can maybe get it up and running and probably I might have to replace those dried-out caps in there as well. so I'm not sure if it'll work.

off the bat. I mean this thing is 52 years old after all and you really have to know what you are doing to actually use one of these things. It is kind of, you know, a non-obvious although you would have been, you know, used to our basic our transistor tester operation back in the day. But you know these days to operate one of these things like how do you measure the collector emitter arm leakage current for example.

Well, it turns out you've got to actually, uh, swap the pins around and put various ranges and you know and do all sorts of things. It's non-obvious and the leakage current and the I gain and things like that. it's just you know it. You read the manual and it's sort of.

you know they say oh I put this to here and this to here to do. You know to measure this and this and it's not obvious how to actually do. it all and press this sucker up here and do all sorts of stuff. So it's it.

Really is a bit a car. It's quite a bit of complex kit that can do lots of different stuff as I said can do the noise. It can measure out noise as well, only does it at the one kilohertz of course and and it does it equivalent to a broadband. So it generates one kilohertz and then it just measures broadband.

They don't have a a filter on the other side - actually I get that out. but they say in the manual that oh yeah, you know it's near enough. it's you know, We've done tests and it's good enough. You don't need that uh, filter in there.

You don't need expensive filter parts or something like that. but yeah, this can do lots of fantastic stuff I Hope it still works I Really would love to get this puppy up and going of it. You know I mean it's just just for kicks. There's no practical value in having one of these these days.

So I hope you enjoyed that teardown as much as I did. It's just a gorgeous instrument they don't make anymore. I Mean you know I don't even have a transistor tester in the lab I invite us I'm crappy two-dollar multimeter with some crappy transistor tester in it. but that basically I you know, haven't used the transistor tester for maybe 20 years I would be guessing I just haven't had the need to.

It's just not something that you typically need to do anymore. I Mean some people, might you know? but gee, it's just you know we're back. When in these days when transistors cost, you know, dollars? Tens of dollars each? they were, you know, very. you know, prized components and not just like Point Zero Zero one sense they are these days and just throw away and you've got you know, Massive, fully characterized data sheets and everything like that.

and well, you know you don't bother, are salvaging transistors like you did in the old days. But yeah, there was a time when owning a transistor tester like this was the Ducks guts it really was. So if you want to discuss it, jump on over to the Eevblog forum links down below for the manual for this thing that has the yeah schematic and all the info. Highly recommend you take a look at that and as always, if you like tear down Tuesday Please give it a big thumbs up.

Catch you next time you you.