FOR 27 MHZ CB?

What is the main use of this device please?

👌👏👍

Thanks for this, I learnt a lot and the individual filters is a great idea.

thank you sir

Hi Ron, I am seeking an RF amplifier that can input 250mw and boost to 3 watts+. Frequency range is 470-480mhz. Do you have any recommendations? Is this something you could make? Thanks!

Мудрость древних, навесной монтаж над полностью покрытым медью двухсторонним текстолитом, усилитель класса AB, трансформаторы на марганец -цинковых сердечниках из сетевого фильтра, комутация на реле со схемой детектирования сигнала на диодах

Hey Ron! I hope you have success with my QCX-Mini. 72/73

I found your You Tube Channel!

Recently found an old BLF578 ldmos device that had failed. Measuring it i noted the failure on one side only. I threw it at a PCB along with a few variable Cs and a few inductors and wham ! 400W out with 1.5w in at 40v on the Drain, 80% efficiency. Based the circuit on the MRF174 data sheet. Great use of a device that was destined to be scrapped. Might end up on 6m as a ft8 PA. 73 from ZL.

Ron, Where did you get the pad cutter?

very nice! 73

Very nice and clear instructions. I'll build this amplifier later this year. Thanks de OZ1BXM Lars

Awesome, instructive, good info

Great video 👍 Thanks ❗

Great amp! And a great presentation! Tks es 73!

The real ham radio spirit 👍🤩

I Want fm 88-108mhz

88-108mhz

What happens if you try to use on higher frequency? Still work just less output? Distortion? Nothing? Im curious. Thanks for the video

Awesome video

That is what I call a really informative practical video. I have a few of those transistors. I intended to use them with a construction similar to the book 'building a transceiver' by ei9gq. I was impressed by the results from your construction, so I think I will try both. Your construction seems to use simpler transformers, so I will kick off with yours. I will be interested to see how your construction would work with more bias up to around the linear position for ssb. I will also try using a simple 50 ohm attenuator padder at the input and see what happens. Thanks for the video. Keith G0ODU

Agree with others: this is a very good troubleshooting video and excellent instruction on peaking the LPF. That's the only hairy thing about the QCX series: reworking the coils to get the proper power out. And it's why I prefer the "plus" kits; there's more room to work. I just put puddles of solder on the toroid holes and soldered the toroids to them rather than _through_ them. Still in all, I just managed 40 Vpp (approx 4 watts) and settled for that. It's hard to believe that the mini is the exact same circuit but fits in you shirt pocket!

Nice little project. I would have used a pair of slightly bigger devices... go for 70W but what you have there is a nice compromise between supply current and heatsink size etc

Hi Ron, nice to run across you on KZbin. I gave you a thumbs up and subscribed. The QCX 50W PA you helped me with on QRP Labs groups is working just fine. I was going to order a 40 and 30m QCX Mini but might opt for one of these models instead. The most noticeable difference to me is the power button, which is nice. 73 Brent

Ron, thanks for the video, good luck to you! Greetings from Russia!!!

Is they the XYL playing the piano in the background? Thanks for the video Ron. +/-~2years later.

Do you have a link to that rotary saw with spring loaded tip? I could use one of those.

I’m sure it’s a good video but I can’t hear you volume all the way up so yeah your audio is way too low

Thanks. 73s kb9jzk

Excellent video. Thanks for sharing.

What a nice vidéo !!

Beautiful circuit.

Hi Ron, really great video... Thanks for the clarity of explanation and the effort you put for this. 73 de Vic, I2GPT

I would have liked to hear what the symptoms were before the repair.

Nice job. 73’s KG4LAH

Excellent video. Great for a beginner like me. Would this amp work on top band? 160m? If not, what would need to be changed to make it work at lower frequencies? Thanks!

Hello Ron! Enjoyed watching your DIY project, Thank-you. I observed couple of points, 1) The binocular core names on schematics are marked wrongly, names just need to be swapped. 2) At 20 mA bias current, i could observe some crossover distortion, anyway you did increase the bias to 30mA. It probably would have fixed the distortion too. Thanks again! Best regards, bp (I am just a DC to RF enthusiast, not a ham)

Ron, put more videos, they are very instructive. 73 of PS8AJR BRAZIL.

Nice QRP, what a patiente!!! Congratulations Ron

Great video sir! Full of information.

Excellent video Ron!! Thank you, your English is so clear, speed is rigth. I really appreciate your video !!!!

Gracias por compartir su conocimiento muy bien explicado. saludos desde CD. Juárez Chihuahua MÉXICO!.

What is that flux?

Can it be used with VHF UHF ? frequency 144mhz and 400mhz Plus?

i enjoyed watching, thank you for the effort and uploading the video, much appreciated.

Great Aid in trouble-shooting. Thanks Ron!

Ron very nice thank you!

Good video, I have worked on several tube amplifiers but never tried my hand at a solid state one.

Thanks Ron. It’s a fun little radio and your presentation was very helpful,