#55 HAM Radio Tutorial: How to make a low end SWR/ Watt- Meter reading PEP power

[@johnwest7993]

I find it interesting that thanks to his intellect and careful word usage he uses his imperfect English to actually improve his circuit explanations. I have yet to fail to understand anything he has explained. He is one of the very best tech teachers on KZbin.

[@TheFunkman]

what a great channel! After repairing radios for many years, I still learn something every time I watch your videos.

[@TRXLab]

+Rudy Rutenber Hi Rudy, thanks for feed back. I'm glad that you like the videos!

[@hancecrawford]

Peter it is great to see an engineer at work you are a great designer :)

[@TRXLab]

Again thank you John!!

It's so beautiful how you guys in USA/Europe have acess to a lot of lab equipments for that low price! What a beautiful lab you have there!

[@budleyca1]

Navarro Eletrônica It's not such a low price as you would think, huge investment there...

budleyca1 Minimum wage where in Brazil is around US$230/month, and any test equipment arrive with 80% of tax, so a simple Fluke 179 you need to work 2~3 months to buy. Imagine the price of a MSO.

Electronoob: Geeking Out Yeah! I'm really trying to get abroad to do a Master Degree (and I really wanna work with Space Electronics)

[@budleyca1]

Navarro Eletrônica Wow, that's a crime...

[@budleyca1]

Navarro Eletrônica Stick with it, all is possible if you really want it...

[@dennisqwertyuiop]

Excellent thank you for sharing thats the first time your on camera ,Hansom man Peter

[@karlfell3768]

A great little circuit, thankyou for sharing Peter, nice to be able to put a face to the voice. Keep up the good work and looking forward to many more videos. Karl

[@TRXLab]

Karl Fell Hi Karl, thanks for comment, the circuit works really great. All the best 73

[@RC-Heli835]

Wow! You nailed it on this one Peter! You are one amazing radio man!😀😀

[@williamvancoller3421]

There is a slight DC offset where output opamp does not have the ability to switch to 0v with single rail supply. You should place two diodes in series from opamp2 output or zener to essentially lift output of opamp above 0v.

[@Beretta96Dan]

Another very interesting video! I enjoy watching each one, and since they are not in any particular order, I will eventually see them all. Thanks for the work!

[@TRXLab]

+Beretta96Dan Hi Dan, thanks for comment. I'm glad that you like my videos! 73

[@andrewverran3498]

love the way that you have designed the perf board layout on the Graph Pad, as soon as i heard the word DUMMY i felt comfortable ,please do a DIY for a 2 tone ssb linearity tester. PLEASE. cheers from OZ

[@joelkist6493]

I watch and re-watch your videos: GREAT!

[@dakloverextroidinaire3122]

great video you are very smart man and i love all your test equipment i learn a little bit more each day i watch you in action ,... don't ever stop ,.. you are helping so many people ,...which is what the hobby is all about ,...... 73's from W2BLM

[@TRXLab]

daklover extroidinaire Hi Douglas, thanks so much for your nice feed-back. Yes you are right that is what this hobby is all about. 73's Peter

[@user-su5sq5ib3i]

Hello! I was wondering what value you changed the drain resistors of the RC circuit to. Thank you!

[@blpblp-tj7ux]

Very interesting...it sure would be nice to know what specific component values were used in the detector, as well as the trim pot.

[@TRXLab]

sorry don't remember it is a couple of days ago :-)

[@hectorpascal]

Nice work, but it was a great pity Peter didn't show HOW Daiwa had tried to implement the PEP reading, and WHY it didn't work!

[@technos123]

Another great video. You videos always make me want to reach for my soldering iron and start soldering.

[@TRXLab]

technos123 Hi , thank you very much. Well if I can inspire you that makes me really glad! Let us know when circuit is up and running

[@charlieoscar09]

Another great video Peter...Liking the IN FRONT OF CAMERA START thanks for now.

[@TRXLab]

charlieoscar09 Thank you very much! Glad that you like it.

[@johnschroeder6288]

Thank you, Peter. The project is well explained and demonstrated.

[@TRXLab]

John Schroeder Hi John, I'm glad that you like my video... Thanks for comment.

[@jimmcdowell8504]

Thanks for a great video. Mr. Carlson's lab mentioned you and this was the first video I watched. I subscribed and an looking forward to watching more. Thanks.

[@TRXLab]

+Jim McDowell Hi Jim, thanks for sub! I'm glad that you enjoy my videos. Thanks to my friend Paul for introducing my channel to you. All the best!!

[@1903A3shooter]

Great looking lab, W4GSM

[@Ldighera]

Thank you for your very clear, concise, and professional presentation. Q: Is it not necessary to have a second similar 'PP' circuit in the Reflected Power meter circuit in order to retain the cross-needle SWR function indication?

[@TRXLab]

Thanks for feed-back. Yes in this example the rev power can't be read in pep.. 73

[@fredbos5997]

Nice instructional video! I think I will rebuild my Pep meter one time in the future. Greetings, Fred

[@TRXLab]

good luck with the project

[@jimgiordano8218]

Nice little project to add to my meter. Simple and easy, and I have all the parts. Thank you!

[@Ianistrip]

Nice work ! a completely schematic diagram(& how to conect)-for download must be helfull. Thank you

[@MrCarlsonsLab]

Awesome Peter! I had to pause the video to say, "nice to meet you!" Great to see you on camera!!! Ok, now I un-pause and watch the video..... Then maybe another comment :^)

[@MrCarlsonsLab]

Mr Carlson's Lab Ok, I watched the full Video now. Looks great, I have the same Watt meter here, so I will have to build the circuit now :^)

[@TRXLab]

Mr Carlson's Lab Hi Paul thank you very much! You know why :-) We will hopefully see when your circuit is running ... 73's

[@TheRadioShop]

TRXBench Great video and well explained. I have a Bird 4304 RMS meter I like to do this to. It is the one without the slug. 15 to 500 watt. I also have the Telewave which is identical to the bird. Thanks for the video!

[@TRXLab]

The Radio Shop Hi there, thanks for comment. Have fun with the project. 73 Peter

[@cyber38313]

+TRXBench I watched this a little later then most and it was interesting. But after you build and test the circuit, shouldn't you then remove the pot as the meter movement would be in parallel and cause errors in the meter reading?

[@sv1oz]

Excelent job Peter!!! What are finally the R _ C values you have used and which op amp suggest? If there any link to have the cirquit will be appriciated, 73 de DK1OZ

[@poseypapusdiazfamily4630]

Why does meter already have a pep switch position?

[@leopoldoalvarez6787]

Dear petter , thank for your PEP explanation concept .., just ask to you which value Resistance did you put on 1uF capacitor after diode and charge..?, or wast randomize probe it..??, thanks in advancer ....

[@budleyca1]

Excellent design and workmanship again, tnx for sharing... Bud...

[@TRXLab]

budleyca1 Thanks Bud for nice feed back.

[@cyber38313]

I watched this a little later then most and it was interesting. But after you build and test the circuit, shouldn't you then remove the pot as the meter movement would be in parallel and cause errors in the meter reading?

[@TRXLab]

+Joe Loucka Hi Joe, good question, but in this case is doesn't matter as the OP impedance is very low and in a parallel circuit the voltages are always equal only the current is a bit higher but the low impedance can handle it without voltage drop.

[@paulcollins2699]

Nice video Peter ,I'll be trying this one .

[@TRXLab]

Paul Collins Thanks Paul! It's a little project easy to handle..

[@alancordwell9759]

Hey, great to see you at last!

[@TRXLab]

Alan Cordwell Hi Alan, yeah trying out this and that....

[@iw0hex]

Great video, great solution. Thanks Peter.

[@TRXLab]

Pasquale IW0HEX Hey Pasquale, thanks for comment, yes circuit works really nice! 73's

[@PeterWalkerHP16c]

Nice *_pep-talk_* :-)

[@TRXLab]

+Peter Walker Yeah nice little project. 73

[@pudiful]

Good circuit. I will do for my cheap meter. I like your videos. Thank's for good videos.

[@TRXLab]

+pudiful Thanks you and good luck with the project!

[@kevindrury8390]

Do you publish your projects on a webpage? So we could print the schematic. Thanks

[@TRXLab]

I'm sorry Kevin no web page....73

[@loundbirder]

Shame you could not provide a schematic with parts list for us learners HI HI

[@osvaldogustavo]

Could you send me an email with scanned photo of the circuit and a list of components? Thank you so much for your video lecture, you are a great teacher!

[@supyrow]

this is my next project for sure! thanks for sharing!

[@TRXLab]

su pyrow Thanks for watching and feed-back! Good look with the project! 73's

[@alb.7763]

It was a good video(project) Peter, Thanks for sharing!

[@TRXLab]

+Al B. Thanks for feed-back! 73's

[@helderguerreiro7177]

Okay, I have a SWR / Power Meter Voyager kw-825 and I need to make it more accurate. Where can I find documentation? Thank you

[@TRXLab]

documentation? for what?

[@helderguerreiro7177]

sorry, I need to check my swr / power meter analyzer because the trimers have been changed. Is there any documentation for this? tank you.

[@CT1JRZ]

Very good job! Works great. Super project, thanks.

[@TRXLab]

***** Hi Victor, thanks for nice feed back! 73's

[@AG8000]

Wäre schön wenn ihr euch mal das Daiwa cn 901 hp3 vornehmen könntet, in deutsch wär gut. Aufbau, Messgenauigkeit etc...Danke.

[@BobMellor1954]

Thanks Peter, great video, useful information. Regards bob

[@TRXLab]

+Bob Mellor Thanks Bob!

[@dethehe2440]

Is 1.7 a bad swr reading or no because u wauld like to know if it is damaging my rafio

[@TRXLab]

+Det Hehe No a SWR of 1,7:1 is okay. Your radio will not suffer up to 2:1 and in critical situations it can be up to 3:1 But do not use the radio beyond 3:1 that is really dangered to your radio.

[@cadiscase]

Could you do this for a Heathkit Dual SWR/Watt meter ? Thanks

[@TRXLab]

+cadiscase Hi, yes this modification can be done on any meter. Thanks for comment.

[@Dennis-mq6or]

Bad design with the op-amp part of the circuit. Your meter jumps from zero watts to something higher than zero watts when you power up your PEP circuit. The meter should not move at all when you switch the peak detect circuit on... The rest of the design is fine; although it might be nice to add one more potentiometer to modify the discharge time of the peak hold capacitor. Dennis O. #12

[@uN1Qu3DZ]

This is due to the LM358 opamp not being "rail-to-rail" - that is, the output can never be equal to the positive or negative power supply rail, and in this case, negative supply of the opamp is ground so zero volts; the output will be a small value but something higher than zero. Using a higher-spec opamp will solve this problem, look for "rail-to-rail output" and "common-mode input range includes ground" as search keywords and you will quickly find some suitable parts. I think what he wants to show is that you can get good results with very common parts - if you want high accuracy, you are going to use a more expensive opamp, the rest of the circuit remains the same.

[@Dennis-mq6or]

You can even do it with an old 741 series op-amp because it is only amplifying DC. (although I would have also chosen the LM358 for the task).... The rail to rail concept will never be true rail to rail. So you bite the bullet and use two batteries to power the peak detect device instead of only one; and your problem is solved.......

[@uN1Qu3DZ]

Dennis#12 True, using op-amps with a single supply will always be some sort of compromise. Split supplies are the best way to go in any opamp circuit But in many applications a single supply will do and there are plenty of high performance opamps that will operate satisfactorly even with a single supply. It's all about "good enough". :)

[@ghislainballester3391]

Great tutorial, as all the other ones. Thanks a lot, I like the way you explain things in detail. 73/F4HGA.

[@TRXLab]

Thanks for feed back 73

[@djjoep100]

what is a good wattmeter for my yaesu ftdx 3000d for hf on ssb ?

[@TRXLab]

+djjoep100 Hi the best watt meter and of course swr meter for your ftdx3000 is the LP-100 by TelePost, Inc. USA. Hope that helps 73

[@hdmalpas]

Will this addition upset the SWR reading?

[@TRXLab]

+Howard Malpas Hi Howard, no it does not influence the SWR reading. 73

[@hdmalpas]

Thank you, I will give it a go.

[@TRXLab]

+Howard Malpas Good Luck! It turned out that it is best to use 150 Ohm to load a capacity of 10uF and use 100K to discharge 73

[@educatedmanholecoverbyrich8890]

What is the value of the pot?

[@TRXLab]

I have 1Kohm on my mind.

[@4404-e6i]

THIS GUY REMINDS ME OF MY DAD RANDY KOKES OF INDY IN.

[@brianfoley4519]

very well done!!

[@RadioNostalgia]

Really great teeacher ! Thanks !

[@TRXLab]

Thank you Paolo! 73

[@RadioNostalgia]

NO, THANKS TO YOU ! You can publish lessons of electronics for dummies like me !

[@TRXLab]

LOL, I'm glad that you have a use for my videos. All the best 73

[@RadioNostalgia]

I'm really serious......

[@wheelholder12]

great video.

[@TRXLab]

mike charette Hi Mike thank you very much!

[@MAURICIOFALCAOPY5MZ]

SENSACIONAL Peter!!! I'do it !!

[@TRXLab]

Mauricio M. Falcao Hi Mauricio, thanks for feed back! Great that you are going to build the circuit.

[@joseabrahaoabrahao7937]

I am Emílio Abrahão, I speak of São Paulo - Brazil. I subscribed to your channel recently and you approach maintenance quite broadly and I like it. You repair and restore various old equipment, HF radio and other interesting equipment. You give us the possibility to find solutions where we could not find without guidance. I like it when you show old measuring instruments like analog and digital multi meter. I'm trying to recover my old analog multi meter, but I'm having trouble getting specific components for it, but I'd like you to help me get those components. If you can help me, I'll tell you what the components are, and then you let me know the component prisoner and the post office. See you later.

[@michaelcastro3169]

thanks of Brazil!

[@TRXLab]

Thanks for watching Michael. 73

[@r.f.lab-renefilho1453]

Great explanation ! 73. PY2NDB

[@TRXLab]

Thank you Rene 73

[@notfallmed]

Great, tnx. 55 73

[@TRXLab]

+notfallmed Hallo, vielen Dank für die Rückmeldung! Alles Gute und 73

[@RakeshKumar-dg5of]

Aooodio...Aoodio..