hpr-knowledge-base/hpr_transcripts/hpr2394.txt

Episode: 2394
Title: HPR2394: The Lost Episode
Source: https://hub.hackerpublicradio.org/ccdn.php?filename=/eps/hpr2394/hpr2394.mp3
Transcribed: 2025-10-19 02:14:06

---

This episode of HPR is brought to you by Ananasthos.com.
At 15% discount on all shared hosting with the offer code HPR15, that's HPR15.
Better web hosting that's honest and fair at Ananasthos.com.
Hello, this episode was recorded in October of 2016.
It was supposed to be a three-part series on transistor testers.
So the one you're about to hear, and then I had recorded a second one, but it wasn't edited together.
However, during the recording of that one, a good friend of mine, well, a good friend of everyone in our Linux user group passed away.
And I had mentioned him in that episode, and he was part of that episode.
And it was a bit too raw at the time to finish working on that one.
I'm not even sure if I still have the recording. I would put it up if I had it now.
Mr. Pico, but anyways, here is part one of transistor tester kits, because someone who went by the name not verified in the comment section of HPR,
I don't know if that's his actual nickname, or he just didn't put a name down.
But he asked if I had ever put together any of these transistor kits, and I have a couple of them.
So here is an old episode I did way back when that I still had on this H1 Zoom SD card.
And I'll put it up, and Mike Ray will be happy because there's more clicking on the bench going on.
So, okay, enjoy.
Hello, this is Envoy Bill, and I'm here with another electronics kit to do a HPR on.
This one I found on eBay, it's called, well, it's a really long name.
I don't know who makes it, it's like in Chinese.
What it basically is, it's a transistor tester. You can take a transistor, you put it in this little zero force insertion little jovy thing with a handle on there.
And it will tell you if it's an NPN, a PNP, it will try and classify what type of diode you have there.
It also says it's an LCR meter, which is inductance, capacitance, and resistance, so you can test inductors, capacitors, resistors with this little kit here.
It also says it's ESR, which is effective series resistance.
It says it will test frequency, and it says it will generate PWO pulse width modulation.
All of this in a kit for $13.95. It seems a little far-fetched, but I just had to get it, and let's try it, and let's put it together, and see if it's actually handy.
I like to get these little kits. I mean, I have some better equipment on the bench, but these kits are fun just to build, test them out, play with them.
You learn a lot while you build these, you learn even more if you have to troubleshoot them.
And as I gather these things, I assume someday, if any of my nieces or nephews or something start getting into electronics, I'll have some pieces of equipment to give them, or extra kits.
And they can build them themselves, or they can use these test kits, and I don't really have to worry about them, like smoking a $700 meter or something.
They can just, you know, take these home, play with them, learn from them as well.
So I found this on eBay. You can too. There's a couple different ones. This one has a color LCD screen.
I see some other ones that are just kind of like a green screen. It's still LCD. It's still LCD, but it's like monochrome.
And they come from all different sellers, and I don't know if it's all different makers again, but here we go. Let's build this thing.
So I started with this at the last plug we had. I don't know when you'll hear this, but the last plug was what? A pull, but I think.
And I was just populating the resistors. Sometimes that's, I mean, it's not difficult, but sometimes that's the most time consuming thing on these, you know, inexpensive kits.
But they don't mark what resistor is what they know. Sometimes you get a kit, a nicer, a higher end kit, and they will still have the masking tape on top in the bottom of the resistors.
And someone will pencil in, you know, this is this. It's not a big deal to find out what a resistor is, but when you have to go through 40 of them or 20 of them, that it's just, it's just time consuming.
So at the log, I was, I had my meter out, and I had this neat little, where's my phone?
Oh, you can make that another HP.
And I was going through all the resistors to figure out which ones which and just stick them into the board as I went.
The other, well, interesting thing or thing I'm seeing more, more often now is five band resistors are coming out. Well, they've been out, but they just seem to, these kits just seem to come with five band.
They can be a little more tricky. So be careful when you're trying to figure out which type of resistor you have, because the fifth band on there is usually brown, which is one in resistor.
But, well, that stands for 10% on the back end, but often a lot of resistors start with one as well. So you're going to have brown on one end and brown on the other, and just colors in the middle that you've got to figure out which ends, which a handy thing to do is get your meter out, stick it in the ohms, read your bands.
See what you think it is. You can write it down if you want and then test it with your meter. It's going to come with, you know, within 10% like I said.
And it's just a better way to double check which resistor you have is which, because I've been doing this for years, and even sometimes I still mess up a resistor here and there.
At the log, I populated the resistors, and just before I turned this recording on, I soldered them up. I took a picture of these things here.
And I thought, well, why don't I kind of build this kit as I record, and maybe some things will come to mind that I wouldn't mention, you know, after the fact, a day later or an hour later.
So two things I thought to mention is you could get a, if you look at some of these pictures, you might see a black vice with blue legs, and it holds a PCB board.
These are really handy. I got this in Amazon. They're not expensive. They're like 20 bucks. You can get more expensive ones. I think it might be called panel tilt or something like that, but you can get like 100 or $200 ones.
It's just like a, it's a third hand, but it's not that alligator clip thing. I think I find those kind of useless. Those two alligator clips on a little tripod with a little magnifying glass. Don't bother with those.
This is better. I should find the name of it. If I do, I'll put it in the show notes, which one this is. I've, this so far, this one's been good.
It holds the board well, and you can just, you know, you're going to hear it right now. There you go. Sounds from the bench. You can rotate it, you know, populate your board on the top, rotate it, solder things up.
So I just, I populated the resistors, spun it around, soldered that up, then turn it around, populated capacitors, diodes. Oh, this diode, I didn't solder very well sticking up. I'm going to fix that.
And the little crystal and the LED. If you heard the episode I did, the first DSO 138, the little oscilloscope kit, they kind of step you through building up your project, and they'll have you put the smallest components in first, which is the resistors. And then, you know, next was, I don't know what was next, probably the crystal.
And you, you slowly step up and stack your board up with taller and taller things, because if you put the tall things on first and you spin it around or you put it on a table.
Well, let me step back. If you put the tall things on first and solder that, and then you put like your little resistors in, and then when you spin it around, the risks are just going to flop down and trust me.
Put the low profile things on first and then build your layers from there. So here I am. I just turned the recorder on. I got the resistors in place. The caps, like, the little caps, which are pretty small. Sometimes those get big, but these were small. So I threw them in LED and crystal. So I'll go from here.
I just spun it around again to fix this diode, which I didn't really, I didn't realize it flopped down when I spun the vice around. Now it's sticking up like a half an inch. That's so good.
All right, I'll just, I'll pull it right out.
Ah, here's another handy. Anybody want to figure out what that is? We'll do a little quiz noise quiz here. That is a solder sucker. I just pulled this diode right out, but it filled the holes in in the PCB board.
So I want to suck the solder out of them so I can install this diode again and do it right.
One, two, three. There we go.
Spin it back around and put this diode back in. So the solder sucker is like, I don't know, $12, but they're really handy. If you want to spend a lot more money, you can get a solder sucking station, which looks like a big solder station, but the gun has a button with a vacuum on it.
You go in your solder and you press this button and it sucks.
I suppose if you were like pulling apart boards, just to salvage parts, like whole entire computer boards and things, that would be the way to go. But for the one off thing, like I just had to do just the cheap little handheld one works fine. Where are my needle nose?
I can tell this can be another one of those episodes where there's just like a lot of side talking and me getting distracted.
Okay, let me throw this diode back in.
What it was was when I stick components in, I reach behind the board and I bend the pins, display them out. So then it'll kind of hold the piece in position in the board. That one was already in like a little forest of prongs and I didn't get my finger in there.
I didn't play the wires out and when I spun the board around, it slipped out before I knew it and I had it soldered in a weird way.
Let me solder back in.
Oh, another handy thing. I got one of those magnifying glasses with the LED light on arm.
Believe me, some of this stuff is so small and the older you get, the smaller it seems to get.
I'll take a picture of that as well. That was on eBay as well or no, that was on Amazon.
Okay, diode just. Well, here, I'll take a picture right now of the...
So this picture is the, that little third-hand vice that I use and the LED magnifier.
That's not very good.
I'll see if I can find that in the show notes as well, but that's not cheap. It's like a hundred bucks, but I like it and my wife stole it once.
I brought it to her jewelry making bench and I had to steal it back and I got her a white one and I kept my black one.
So it cost me two hundred bucks for this light.
Okay, let me...
So that's the resistors on and the next kind of size components. I'm going to go down to the garbage and clip these leads off.
If you clip these leads off in your room, they go flying everywhere and they get in the rug and you're going to step on them and you're going to get one in your toe.
Speaking from experience.
Okay, because there's no rules I have to figure out which components I want to put on next. Let me see what we got.
We have...
We should send you a little picture with this, but what do you expect for $14?
There is the rail for the... there's a little... probably a rotary encoder.
Rotary encoder, it looks like a potentiometer, but I can tell by the way it's clicking. It's a rotary encoder.
And this bag is the CPU, the main brains? Oh good, and they give you a socket.
So you don't have to... oh, it's an app now. That may be good. Let me get this back here.
That may be a 32-328b, so maybe this is our greener base? I have to look that up later.
Okay, that's going to fall right out as soon as I turn it over. So this is when I tape it down.
This is the socket for the main CPU.
Flux pens. I like these. I like the alcohol one better. They do have water-based and alcohol-based.
I used to use flux paste, or like a flux liquid, and a little tiny paintbrush, but these are just so much easier.
It's like a marker. You just push the tip down and it will float some alcohol or water-based flux, and you can just kind of just draw on your board. It works well.
I'm going to have you guys spending like a hundred bucks by the time of those if you want all this stuff.
If my voice changes, it's because it's going behind this magnifying glass thing again.
You're also going to want a needle tip for all this stuff. I used to, way back when, only have one tip for my soldering pen.
I actually set that soldering pen to Jezra, because he had a crappy soldering pen, and when I got the Haco here, I didn't need that anymore.
I sent it to him, and luckily, just before I sent it, I did find my little bag of tips for that.
He's got a big wedge shape to desodder. If you buy a soldering pen or you buy a soldering station, see if they have a tip package you can get.
They'll send you six or eight tips. For a lot of electronics work, you're going to need this little needle tip.
If you get into bigger things, or something with a larger surface area, of course you need the bigger tip, just to transfer all that heat.
You want to transfer heat quickly so that you don't damage the board or the part.
So, something larger needs to heat up quick. Melt your solder, get off it. If you use a small tip on something with a big surface, you're going to be sitting there for like two minutes.
It's going to really heat up a localized area, slowly dissipate out. You're going to damage the board.
So, use the right tip for whatever your soldering. That's my tip for tips. I guess.
Okay, there's that. What else do we have to put in this zero force?
Jesus, it doesn't say which direction it should go.
I suppose it doesn't matter. I should look at the picture on eBay.
Okay, they show it with the handle to put your component and you run this handle down and it locks into the component.
They show the handle. Oh, it's drawn on the silk screen. Yeah, there's the little handle.
Never mind. If you get this kit, you'll figure it out quicker than I did.
So, that's going to take some tape as well. Actually, that's a pretty tall part. I'm going to do these next.
It is a little terminal, a little screw terminal. I can see the one here is to do your pulse width.
One is to do. It's outputs. Outputs for different types of waves. Let me do those next.
Okay, there's those. Next, it will be. This looks like the header for the screen.
Where did that zero force thing go? See, I turned the board around and it fell out.
I'll tape these two down.
My tape fell out. Both pieces of tape. Okay, I'll start that over.
Okay, here's another trick. This big giant zero force thing. You're not going to burn your fingers on it.
You can pre-put the put flux on it. Now, just hold it with your finger. Hold the top of the zero force.
Turn the thing around and just tag one pin.
And then on the other side, the opposite pin. I hope you more solder it.
If it was like a capacitor or a resistor or something, you're probably going to burn your fingers, but this won't.
So, that'll just hold it in place. You just solder the two opposing ends in and then you can just go for it right across the pins.
I'll do the same with the LCD header.
What's next? Got the rotary encoder. That's it? The rotary encoder and the, where you can plug in DC power.
Let's put DC power jack.
And they give you some stand off so you can make a little stand to lift it up.
Oh, oh, there it is. I was just opening the screen. They give you a header for one side of the screen.
And then I didn't see any pins for the other, but it's actually in. It's in there. You got to solder those on as well onto the screen.
I think I'll just do this right on the table. Rest the screen on the table. It'll hold the pins in place and solder right there.
Okay, I think that is it. I just got to pop in the at-mall, which I seem to have lost on the table.
Oh, here it is. Since I'm an anti-stack foam.
Let's install this in the socket.
The legs are always split out like slightly too much. I don't know how to pick and place machine to do this.
Okay, there's that in. And install the screen.
And get a nine-volt battery and see if the blue smoke comes out.
There's no on-off switch, so I'll assume you just plug the battery in. Let's see what this thing does.
It does nothing. Okay, let me just going to recheck all my connection. Let me make sure that at-mall is in proper.
Oh, there's a dry joint right there on that transistor. This is why the magnifiers help.
There is a capacitor that I didn't even solder. Okay, check your work people.
What else? I should have double checked this before I put power to it, but well, if you heard some of my previous kits, I just go for it.
Okay, I think the last thing I said in this podcast was let's power it up and turn it on. That was like two days ago.
I put power to the thing and nothing happened. And I pressed the rotary encoder also is a push button, which is how you start it.
There you go. We can have audio sounds in this podcast.
That should power the chip, which turns out is the atmiga or atmega328, which I've also seen in Arduino kits.
The LCD screen will light up white, but it never boots that chip.
So I went to the internet. I'm poking around. And what it turns out is some of these, hang on, motorcycle going past.
There's like 12 or 16 different versions of this board coming out of China. And there's not too many, too much in the way of instructions or schematics.
And some of these boards are coming out and the atmega or atmiga. However, we're going to say this 328 chip is not programmed.
So what you have to do is program it yourself. So I've found some links to the source code and I found some, well, I think they're instructions.
It's kind of if it's not really English, but I'm getting closer. In any case, this is going to turn into a two part episode.
So we'll get another HP out of this. I'm going to track down the software. I'm going to track down the procedure for programming it.
And I haven't done much with programming since like Arduino stuff. I had a teensy and I, geez, that was years ago, teensy was Arduino compatible.
And I just did some simple like making LCD or an LED blink. It's like the new hello world. And then one of the odd camps, I interviewed a guy was breaded shrimp or something like this.
They sold like a cheap or an inexpensive, not cheap, but inexpensive kit where you could make an Arduino compatible on a breadboard. And I recall buying one of those.
I think the parts are still on my breadboard. So I have uploaded programs to these chips before, but it's been so long that I've kind of forgotten all about it, how to do it.
That will be part two. Hopefully I can find the software, figure out how to upload the program to this chip, get this thing running.
I'll let you guys know where I found what and what I did to get things running. And then I will review the unit, go through the steps, we'll check out some transistors and some MOSFETs and throw some inductors, whatever I got hanging around.
And we'll just kick the tires on this thing. If it does do everything it says it will do and it does it fairly well for $12, it's still going to be a bargain.
So I think I'll leave it there until I get some further information on this thing. This is always fun. The journey is more fun than the actual build. So let's see what I find out.
Okay, if anybody wants to email, I'm NY Bill at gunmarkina.net, still on status net, Janu social, NY Bill at sn.com.net. And I do check the comment section, which I'm finding that's the best place to put things because instead of someone asking a question out on email where it just goes back and forth between two people, we keep it in the community.
So I do like the comment section, I check it every time, if we want to have a conversation there, I'll be checking it. I'll talk to you guys later.
You've been listening to Hacker Public Radio at HackerPublicRadio.org. We are a community podcast network that releases shows every weekday, Monday through Friday.
Today's show, like all our shows, was contributed by an HPR listener like yourself. If you ever thought of recording a podcast, then click on our contributing to find out how easy it really is.
HackerPublicRadio was founded by the digital dog pound and the infonomicon computer club, and is part of the binary revolution at binwreff.com. If you have comments on today's show, please email the host directly, leave a comment on the website or record a follow-up episode yourself.
Otherwise, status, today's show is released on the creative comments, attribution, share a light, 3.0 license.