#77 Shop Talk Build Your Own Test Gear

Discuss this on my site
gokarters.com/smf/index.php?to...
Link to original design and discussion on EEVBlog
www.eevblog.com/forum/projects...
Alan w2aew review
• #247: Circuit Fun: 5 T...
Contact information
gokarters.com/smf/index.php?to...

[@johncunningham5435]

This brings back the old days when I designed some of my test equipment on a budget when I was starting out. I gutted a transistor analog meter that was defective and converted it to test small and large power type SCR'S using four AA batteries. Not only did it turn on, it would indicate open, shorts and leakage and proved to be invaluable for finding those tough dogs when SCR'S were most common. "Excellent presentation Buddy"

[@josephcote6120]

If I was building this signal tracer I think I'd live with the straight through probe and put the demodulator circuit inside the speaker housing, then add a little toggle switch that bypasses the demodulator for AF and puts it back inline for RF. Maybe even add a little opamp to boost really low signals, adjusted by a gain pot.

[@jimzradios6155]

Thanks Buddy, I built a rf probe a few years back and sitting here I noticed I have a computer speaker, so I have my next project for this coming weekend. I have learned so much from making my own projects from scratch.

[@TheRadioShop]

Cool deal. Will be a fun quick project

[@fullwaverecked]

Hello Buddy, that's a slick way to make a circuit board. I'll have to give this a try. Thanks for your efforts in making these videos!

[@Andrewausfa]

A signal tracer is very useful. I built one in an old ex-equipment case with an LM380N amp, OA79 diode, speaker, a few capacitors and resistors and a couple of hours soldering. I made mine with the demod diode on the strip board and then switchable RF/AF on the probe (which is just an old meter test probe) input. Best of all it was fun to make. I wish you could still get those Heathkit probe bodies! Andrew

[@TheRadioShop]

Man I love those old heathkit probes. I may even look into reproducing some of them. . Use aluminum tubing for the body and mill some ABS for the ends. Thanks for sharing.

[@jaybats7865]

That’s so awesome to re-purpose old equipment. Thanks for the fun👍

[@winstonhuxley5064]

Not sure if you guys cares but if you are bored like me atm you can watch pretty much all the new series on InstaFlixxer. Have been watching with my gf for the last months :)

[@kasontrevor966]

@Winston Huxley Yea, have been watching on instaflixxer for months myself :D

[@justusjaxx1238]

@Winston Huxley definitely, I've been using instaflixxer for months myself =)

[@ameerdrew3649]

@Winston Huxley Yea, I have been watching on InstaFlixxer for since december myself =)

[@supyrow]

I love making my own test gear, i gotta make some video on some projects ive done... one of these days :) Thanks for sharing and for taking the time to do this!

[@TheRadioShop]

Please do. I will watch. Thanks for stopping in brother

[@larryk4mu240]

Hi Buddy, glad you are finding time to make videos again, most enjoyable. Hope life is returning to near normal again. I'm looking forward to not only the 101 series, but also you getting some videos shot with your microscope, that will be so cool... 73

[@TheRadioShop]

Thanks Larry. I have a few pieces of gear to work on coming soon. Will have to use that scope for those.

[@harryconover289]

I’ve always found that homemade tester is the best because you understand it so thoroughly the 260 I would document but this one had the pin jack I hate Those style I still use my 260 as my reference it’s amazingly good condition they last forever I’ve had that one 30 years

[@PelDaddy]

Nice tools. I love the re-purposing of the Simpson. I have an old Triplett 630 in similar condition regarding the corrosion. I thinks its movement is a little different in terms of uA, but could be used for something similar.

[@TheRadioShop]

Thanks. Sometimes those meters have a resistor in them. You can change that to what you need to make it work. To a certain degree.

[@injoelsgarage3934]

Glad to see you back on channel. We have a lot of computer parts collecting dust let us know if we can help in that area. Great videos thank you for sharing. Hope you and yours are doing well after the storm. Joel

[@TheRadioShop]

Joel, Thanks for that. Will let you know if I need anything. We are doing ok now. Life moves on.

[@bigslick]

Great video, kudos. Regarding the computer speakers signal tracer project, I would think the amp gain would be insufficient for many signal tracing needs because the input of those PC speakers is always LINE LEVEL, which requires a rather large signal to get any degree of audio output. I would think that an extra preamp stage would be required to make the PC speakers more useful for this project.

[@CBsGreenhouseandGarden]

Great tips Buddy! Thanks for sharing.

[@TheRadioShop]

Thanks for watching

[@lesleyra0424]

Great idea for an old set of PC speakers and reworking of an old 260 Meter

[@TheRadioShop]

Thanks Richard

[@LL-jc6gh]

Glad you are back up and running 😀

[@TheRadioShop]

Thanks Lou, good to be back

[@thomasfrank4742]

Hi Buddy. Nice Video as always. Will keep the signal tracer in mind and put it somewhere on my (too)long to do list. And please remember: there are people out who do backups, and other who will do ;) 73 from Munich

[@TheRadioShop]

Thanks Thomas. I mostly back up weekly. But gotten so busy I let it slip. Big mistake.

[@PapasDino]

Glad you're back in the rotation Buddy...sorry it took so long to comment but the KZbin new video notification system is having some problems and it took me a while to figure out there were new episodes on several different channels. Keep up the great work! 73 - Dino KL0S

[@TheRadioShop]

Hi Dino. Yes notifications have been slow coming in. Half the time I do not notice them because of so many I get from emails and messages. Will get back in the loop now. Plenty to come. Thanks for stopping in.

[@TRXLab]

Hi Buddy, very nice projects! Yes this laser printer layout preparation ie working fine. Sorry I'm late but to may things to do...Take care 73

[@TheRadioShop]

Hi Peter. I know what you mean. Same here and lots of work. Thanks for stopping in 73

[@paul.alarner6410]

j diddy'from eev blog meter is a great design,it works bang on,excelent design for a build,ive 3 of them now based on that deign,good for in circuit testing too,what a clever design!

[@pruff5072]

Cool test gear! Would the signal tracer be helpful to use on an old transistor-only Atlas radio from the 1970's that doesn't receive anything except a faint fm/am signal on one band? (When using a mobile magmount antenna (10 meter))

[@bmn_nc]

Glad to see you on again some. You are really creative with repurposing stuff! 73, Other Buddy W4LON

[@TheRadioShop]

Good to be back Buddy, I always like to find new ideas for old stuff. Keeps them alive. Thanks for stopping in.

[@tecnisdaimondm.g9321]

Excelente 👌

[@radiobigman47]

nice to see you back *

[@TheRadioShop]

Thanks and good to be back on.

[@gd2329j]

Re the balance problem . The meter driver circuit should have matching parts between C3 & C5 . Match C3 with C5 , R13 with R18 , TR4 with TR5 & so on ! I see NO decoupling capacitor so drop in a 100uf across the supply . The 9v pp3 looks a bit small for the job . Thanks for the Video

[@gd2329j]

Note the ESR meter schematics don't match ! See C3 on the 2 schematics ( 10nf & 22nf .W..T.....!!??..... ) You could fit a 500R trimmer & a 1k2 resistor for the 1k5 in the collector of Q3 if nothing else works .

[@TheRadioShop]

Thanks for that information. I have had no time to trouble shoot yet. Will let you know what I find.

[@MichaelLloyd]

That's a great use for that poor old Simpson 260! I saw Alans video too and I plan to make a board for it. I have a few VTVM's that I'm not using if you need a good meter. One is a RCA VoltOhmyst. I have an Eico VTVM somewhere around here. I'm good on QRZ if you want one of them. 73 NE5U MIke

[@TheRadioShop]

Thanks Michael. Just hated seeing that old meter sitting not doing anything. Just may look you up on that.

[@dennisqwertyuiop]

Great idea on ESR meter, and showing your tracer, next question I have a little black box containing a speaker to test mic for modulation but what is your switch doing my speake came with my CB 42 analyzer thanks Buddy

[@TheRadioShop]

Hi Dennis. ThanksThe switch just turns the speaker off and on. That way I have the tone on all the time and control it by the switch. This saves me from having to reach over high voltage tube radios to turn the tone off and on.

[@dennisqwertyuiop]

just as I thought , another good idea you have, will add a switch to my speaker,,keep them coming, again excellent work on the old simpson, now esr

[@TheRadioShop]

Thanks Dennis. You will like that switch mod.

[@wildbanjoman99]

Thank your for this video.

[@TheRadioShop]

And thank you for watching.

[@DonDegidio]

Hi Buddy, Nice couple of pieces of test equipment using re-purposed components. Wish my two sisters would move to their own places so I can setup a bench for testing and building projects. I'm stuck using the washer and dryer for now. :-( Sorry to hear you lost that video footage from the hard drive. Would have been really bad if nothinbg could have been recovered. I think it's time for me to make images of all my drives, just in case. :-) WB3BJU

[@TheRadioShop]

I know that is a touch situation working in a confined space. Perhaps that will change for you. And yes always nice to take something old and make something new out of it. Agree on the drive, could have been a total loss.

[@mikesradiorepair]

Looks like you built some ESR into your ESR meter. I'm sure you'll get it straightened out. Goodie box ready to send to you tomorrow. There's a project in it for you but I think you'll like it. :) Mike

[@TheRadioShop]

Guess I need to test for that lol. I think it is something simple. A project in the goodie box. Cant wait, your goodie boxes are the best!.

[@mikesradiorepair]

+The Radio Shop Lets just say the little power supply board and ARF manual got really heavy really fast. :)

[@TheRadioShop]

Oh boy, cannot wait.

[@mikesradiorepair]

+The Radio Shop Christmas a month early. And better yet its not just a project, its a project that includes repair parts. :)

[@TheRadioShop]

Oh wow. This is going to be great! And going to have a care package for you soon also.

[@msaradio7455]

thank you Buddy! keep these coming...... 2 thumbs up! KK4MSA

[@TheRadioShop]

Thanks Justin. Good to see you.

[@WaterWhiteTuber]

Another Gem :-)

[@maninthevan53]

awesome

[@TheRadioShop]

Thanks

[@bencollins5937]

nice job

[@TheRadioShop]

Thanks Ben

[@junemahinay12]

SIR CAN I ASK THE VALUE OF R 24 IN THE ESR METER ?

[@TheRadioShop]

The value of R24 is impossible to give. Since you have all your parts and the tolerance is unknown to me I cannot pick a resistor for you to start with. Start with a value of half your trim pot value and adjust as needed is as close as I can come up with.

[@jimzradios6155]

I'm having problems trying to register on your site, I can't find the info in the top right corner to put in the last line of the registration process.

[@TheRadioShop]

there are three answers pertaining to different questions. The answers are cross, universe, radio

[@jimzradios6155]

Thank you, it was radio and I'm registered.

[@jonmullins8460]

Got my $1.99 pair of speakers today. Time to start hacking.

[@TheRadioShop]

Cool deal Jon