GIVEAWAY - Improving A Simple FET Regenerative Receiver - Part Three

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This part three of the video about improving a simple FET regenerative receiver ( or at least trying to ). We started with the classic N1TEV regenerative receiver schematic in order to modify it hoping for a smaller but slightly better version 100% made with transistors.
73, YO6DXE.
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[@maxzile4860]

Use green led diode to stabilize current and voltage in the FET source. This varbling demodulation is result of demodulation that change polarisation voltage and capacitance on the gate of the FET transistor.

[@maxzile4860]

Search for example of this: N0WVA’S ONE-FET REGEN OPTIMIZED FOR SSB/CW SOUNDS GREAT!

[@dxexplorer]

Ohh yes thank you so much. That is the 1% I was not happy about 😅

[@dxexplorer]

I know this one and wanted to build it as I really liked it. Thanks for reminding me. Great help for me 🙏🙏. 73, YO6DXE

[@kestutisrimkevicius8891]

With current circuit AF signal is taken from Source and it makes "Infinite Impedance Detector". If you will place green LED to Source, then you should take AF from Drain I believe... Or not?

[@dxexplorer]

@@kestutisrimkevicius8891 I think yes. I will do some experimenting and see how I get it to work ))

[@Chems7308]

Those parts seems very common and yeh..very nice ..and congratulations for 5k+ 🎉

[@dxexplorer]

Yes that is always the idea... to use stuff that we usually recover from old boards 😁. Save the parts and save money ( ha ). 73, YO6DXE

[@nandrews8412]

Congratulations on 5000 subscribers!

[@dxexplorer]

Thank you so much 🙏🙏 73, YO6DXE

[@4youian]

Fantastic project Chip. Looking forward to the PCB version. Congratulations on 5000 subs, big achievement Chip! Take care 73, Ian, VK7IAN

[@dxexplorer]

Thanks so much Ian. I need to get some NP0 capacitors to get the best out of it. Soon you will also have a surprise 😁 maybe in two weeks from now. 73, YO6DXE

[@kestutisrimkevicius8891]

Great video, very interesting, thanks a lot for your work!

[@dxexplorer]

Thank you as well for always watching. Means a lot. 73, YO6DXE

[@pd1jdw630]

Looks good, it’s all about the learning process. Well done buddy. 👍🏻

[@dxexplorer]

Ohh yes that is so true. 🙏 73, YO6DXE

[@bullthrush]

Congratulations, a lot of work to get this far.

[@dxexplorer]

Thank you so much 🙏. I wish I had more free time to make more and better videos but... life is how it is. 73, YO6DXE

[@bazzaar1869]

You have have that working really well, the stability on 20m is not easy to achieve.

[@dxexplorer]

True... but I noticed that if using a smaller value inductance and larger capacitance helps a little. Now I also use some cheap capacitors... let's see how it is when I find some NP0's. 73, YO6DXE

[@mikestokes235]

Thank you, looking forward to seeing your next constructional video!

[@dxexplorer]

After I am done with this receiver I want to return to some simple transceivers that I had in mind for a while and I always wanted to see how they work. But I also have a few more promised videos in between that I must make 😁. 73, YO6DXE and have a magical weekend.

[@CT7ARQ]

Love to win one of those kits

[@dxexplorer]

I can only wish you good luck 🙏. 73, YO6DXE

[@youtubeaccount931]

Yay!

[@bobi_lopataru]

A better mascot for the channel would be a hamster, ask her to knit a hamster. Get it? HAMster? haha

[@dxexplorer]

Hahahahaha. Good point 🤣🤣🤣

[@garthac]

Happy DXing from the Philippines!!!

[@dxexplorer]

Happy DXing to you too and an amazing weekend. 73, YO6DXE

[@arnoldbencz6886]

Super video!

[@dxexplorer]

Thanks so much 🙏🙏. 73, YO6DXE

[@Brian-mp6bg]

Great video

[@dxexplorer]

Thank you 🙏 and thank you for watching as well. 73, YO6DXE

[@nelsonamador5412]

Beautiful ❤❤❤❤❤

[@dxexplorer]

Thank you so much 🙏🙏. I had to delay the video with the winer a little as I moved houses and most of my stuff is still in boxes... but soon. 73, YO6DXE

[@4L1LAT]

This time I am gonna win for Shure 😁😁. Receiver is turning out pretty good. good luck 🍀

[@dxexplorer]

Hahaha... thank you my friend. I am still trying to get the CW signals sound as nice as they sound on the Sputnik receiver. This is the 1% I am not happy about at the moment 😁. 73, YO6DXE

[@rtronicslab1253]

Grate work...🎉

[@dxexplorer]

Thank you 🙏🙏. Not perfect... still learning... but the best I can 😁. 73, YO6DXE

[@SkyLight-c1]

Interesting achievement excellent

[@dxexplorer]

Thank you. I hope by the time I do the PCB version it will work even better. 73, YO6DXE

[@samopalvampirenvonbutlegin8603]

17:10 It would probably be better to use A1018/C1845 pair, or maybe 2N8550/2N8050.

[@dxexplorer]

Yes those work too. What I like is that you can use whatever you have available. And I have lots of 2N3904 🤣🤣. 73, YO6DXE

[@IvanPassos]

Excellent reg radio fte 73

[@dxexplorer]

Thank you so much. I hope the final version on PCB will perform even better. 73, YO6DXE

[@giovannifumatorre2140]

Sarbatori fericite!!!

[@dxexplorer]

Multumesc mult. Mi mancava dire Buona Pasqua. Ero così occupato quei giorni che mi resi conto che era Pasqua solo due giorni dopo. Quindi vi dirò Buona Pasqua adesso...meglio più tardi che mai 😁😁. 73, YO6DXE

[@ramyramdani2425]

i listen from Indonesia

[@dxexplorer]

🙏🙏🙏 73, YO6DXE

[@son3dra]

Great Ciprian! 👍Have you designed a pcb for this?

[@dxexplorer]

Almost... I have the project in progress. This days that is Easter here I will have the time to finish it. I just struggle a little to get the CW signals sound a little better. I think I need to work on either the regen side ( turns number for the regen throtle or the capacitor value) ) or the biasing of the JFET in order to make it sound a bit better.

[@kestutisrimkevicius8891]

Once you have your developed receiver based on BJT (Sputnik), and current one based on FET, would be great to hear your opinion about benefits one vs another. And for future developments, could you try to add q-multiplier to FET receiver (tickler winding will not be needed) and again - your opinion which one of models feels better.

[@dxexplorer]

That is not a bad idea at all. I will sure do that. So far I can tell that the BJT version is easier to control. But I also have to consider that Sputnik is made for only one band so that may also help. I think it would be the same with the FET version if I limit it to one band.

[@kestutisrimkevicius8891]

@@dxexplorer I'm fine tuning my JFET based regen receiver with q-multiplier. One disadvantage discovered - if q-m is built on collpritts oscillator on one bjt transistor, for SSB is tricky to tune as with adjustment of osc amplitude - main frequency shifts as side effect. So from my perspective better to stay with tickler based regen control. Unless to build q-m more sophisticated with cascoded transistors for cancelling Miller effect of the one. btw. JFET infinite impedance detector, or drain detector in general does not require 1M 100p "grid leak" components. they are redundant in JFET circuitry.

[@dxexplorer]

@kestutisrimkevicius8891 That is an interesting result. Yes I think you are right and in a way the results are somehow expected if you think a little logically. So it makes sense this way. Thanks so much for sharing this.

[@MidlifeRenaissanceMan]

Congrats on the 5K How is the CW coming along ?? Have you managed any CW QSOs ?? Mine is still patchy. Had a couple of CW QSOs in the car today. One with another mobile station in South Island New Zealand on 28Mhz which was novel, and one to South Australia on 7MHz. Both were when I was travelling south of Sydney. My head copy is getting better, but I still missed so much. If I keep it up I get better, but there has been a lot of distractions and annoying things like paid work :-)

[@dxexplorer]

Yep... I know exactly what you are talking about 🤣. Same problem here, busy with work and not much free time. CW is bad for me, no time to practice or learn a little better. Maybe this summer things calm down and I get to do it. I really want to as I like it too much. 73, YO6DXE

[@MidlifeRenaissanceMan]

@@dxexplorer 10 minutes a day, twice a day. Start at 10-12WPM chars sent at 5-6WPM spacing. Just in your head is fine. While you are doing other things, like house work, walking or driving. Doing something where you could listen to a podcast or talk radio. Then pick up the pace a little. Don’t go longer than 2:1 char speed to char space. Most rag chew is 15-18WPM around here. We have a QRS net / party every Tuesday night on 7MHz and later on 3.5MHz depending on propagation and what antennas people have. Kicks off around 7:00pm local (+10) 09:00Z. Have a listen on some of the Australian KiwiSDRs. Usually the Tecsun SDR in Araluen NSW is occupied with participants keeping a keen ear out. George VK2AOE of The Art of Engineering has a video about it on his channel. That’s how I found out about it, through him. Maybe have a listen next Monday morning your time. It goes for a few hours. See how much you can pick out. A letter or 3 is fine. The more you do it, the better you’ll become. I can tell you that one of the most rewarding experiences is a CW QSO on equipment you built yourself. There is a certain magic in that.

[@dxexplorer]

@MidlifeRenaissanceMan i am really waiting for those days to have the time. The only time I go to listen to was now testing this receiver ))). I hardly remember when was the last time I put a QSO in the log. Except the last one when it happened to test a battery and answered a CQ ))). Easter comes soon here in Romania so I hope I get to chill and actually enjoy the hobby. 😁

[@MidlifeRenaissanceMan]

@@dxexplorer I had a QSO like that. I was smashing out close to 20WPM on a straight key trying to do an antenna comparison between my 33’ vertical and my Poke-Out-The-Window-Tenna I was hitting the local RBN to see what my dB over noise would be between the two antennas John VK4TJ came back. We haven’t spoken (with a key) in over a year. We had a very quick QSO before I had to get back to my friend who was waiting to see the results. The vertical was around 6dB or an S point better on 40m over the mag loop 20m it was 4dB down. Not bad for something that pokes out a window

[@dxexplorer]

@MidlifeRenaissanceMan I love these experiments when you don't expect much and you end up with good results 😁😁😁.

[@dolnoslaski345]

Hello, could I change the voltage? To something like 6V or even less?

[@dxexplorer]

There will be a few changes to make, but it should work yes. I know a few VFO projects online that are using a similar oscillator circuit and the lower the voltage the better the frequency stability. I wouldn't go lower than 6v though. As for the audio amplifier, there are many schematics online based on transistors that run on 6v as well. 73, YO6DXE.

[@dolnoslaski345]

@@dxexplorer Thanks, I think I'd have to get some low voltage varactor, so the receiver would not have to have a variable capacitor.

[@dxexplorer]

@dolnoslaski345 Yes that too. I usually adjust the circuit to the varactors I have available, so in your case you must do the opposite 😁. I'm not so good in what may work on lower voltages when it comes to varactors.

[@dolnoslaski345]

​@@dxexplorerand circuit too. I am going to play with potentiometer values and possibly capacitor so it would work fine.

[@dxexplorer]

@dolnoslaski345 i don't have the time now with all the work building the new house... but later on I also want to try a version powered at 3v. But I doubt that it will be with varactors, unless is just to cover one band only.

[@PLASMAKVA500]

love these vids so informative! im working on a lightning detector circuit that should resonate at 300khz or just below the am band. Im trying to only hear approaching storms but also want to hear the VLF spherics/static charges at 10khz-100khz COULD YOU PLEASE HELP ME DESIGN A HI SENSITIVITY TUNEABLE RECIEVER CIRCUT?? please dont direct me to the web for info

[@dxexplorer]

I don't know about lighting detector... but I will have soon a video for a really nice VLF receiver... and technically that should also be able to detect storms and lightning in theory. I am about to take a short and well deserved vacation now as I haven't had any in the past four years... but I think at the end of the month I will start working on that. Shoot me an email if you have the time and I will try to send you the schematic of the receiver if you want. 73, YO6DXE

[@PLASMAKVA500]

@dxexplorer cool! Thanks bud & GO HAVE FUN!!!

[@dxexplorer]

@PLASMAKVA500 Thank you so much 😁😁🙏🙏. You as well... 73, YO6DXE

[@agusramdani6495]

Congrats on the 5K 73 ... YD1CGQ

[@dxexplorer]

Thank you so much 🙏. 73, YO6DXE