Hello! To improve performance - you can use a cheap "gate driver" (74HC04 ) and one MOSFET in class E amplifier with impedance matching network. The port of a MCU can`t fast turn on/off BJT transistors, and there must be a network for forcing output from saturate state. It leads to heating , through current and decrease output power and effeciency.
That transmitter has been modified a lot since that video and I do have some diodes on there now preventing the transistors from going into saturation. A class E Amp would be a good project. Maybe I'll build one next season.
@@JohnHamerProjects The shottky diodes are quite good for preventing saturation! It would be better to matching logic impedance to low input BJT impedance (tens Ohms) using wideband transmission line transformers on a ferrite core.
I do as a starting point, but I fine tune it by looking at the current on the gauge in the video. It can be a little tricky based on what type of antenna loading system you have. Other ways I have seen are making an antenna current meter using a CT transformer, diode, and analog voltage gauge or holding an led with load leads near the antenna and tune for brightest light. I've only tried the led trick with a 12x12 loop, but it did work.
It's a great way to learn. I built the first version like 8 years ago and have really just recently had success getting my signal out. I made some changes after making this video that really made the difference. I regularly have people pick up my signal in Tennessee, Mass, and Illinois now. I'm in South Carolina and my previous record was 80 miles to a guy in North Carolina. I will make an update video soon. If you run into any issues, I may be able to help. Also, there is a great group of guys on the LWCA message board that helped me out a lot. Just go to LWCA.net and click on message board if you haven't been there already.
Could you possibly upload the schematic somewhere else? When I try to go to your site it says that it doesn't exist I have found a picture of it on google but it doesn't load in for me. I have been looking around for a simple schematic and you are the only one who explains this project the best. Thanks for making this content!
Hi, I'm in Turkey. I have some experience in DIY electronics. I want to work on LowFer transmitter and receiver that I can use globally. If you're willing to send me a LowFER audio signal from there, I might be willing to make my receiver design immediately and likewise transmit a signal similar to you. Could working with tesla coils, for example, be a way to achieve this? I live in an apartment with 5 floors. I can use radiators for the heating system of the house as an antenna. Or I can design different antennas. If you are willing to work on this subject, we can do some really fun work.
My transmitter is running all the time right now. It currently only sends CW, no Audio. We are restricted to 1 Watt here in the United States, so I don't know if that's enough to get there. I can look for your signal when you get yours built. I am not sure about tesla coils. My antenna is not very different from a tesla coil, but without the spark gap oscillator. It sounds like a fun project to experiment with though.
A few months ago I was too interested in this topic, but then I started thinking that it wouldn't make me any money. I am now interested in cryptocurrencies. There is no direct connection to the subject, but a blockchain can be designed, for example, that works with RF signals instead of the internet. This can be very interesting. Maybe this idea will interest you. Or, a private key with some bitcoin per hour can be broadcast with RF signals. The person who manages to design the receiver receives the bitcoin prize. Such a tap could be a good way to create a worldwide RF network.
Hello! To improve performance - you can use a cheap "gate driver" (74HC04 ) and one MOSFET in class E amplifier with impedance matching network. The port of a MCU can`t fast turn on/off BJT transistors, and there must be a network for forcing output from saturate state. It leads to heating , through current and decrease output power and effeciency.
That transmitter has been modified a lot since that video and I do have some diodes on there now preventing the transistors from going into saturation. A class E Amp would be a good project. Maybe I'll build one next season.
@@JohnHamerProjects The shottky diodes are quite good for preventing saturation! It would be better to matching logic impedance to low input BJT impedance (tens Ohms) using wideband transmission line transformers on a ferrite core.
How did you tune the antenna; with a VNA?
I do as a starting point, but I fine tune it by looking at the current on the gauge in the video. It can be a little tricky based on what type of antenna loading system you have. Other ways I have seen are making an antenna current meter using a CT transformer, diode, and analog voltage gauge or holding an led with load leads near the antenna and tune for brightest light. I've only tried the led trick with a 12x12 loop, but it did work.
Very good
Thank you.
hi,can it work with emfad ug 12?
Holy crap I wish I was this smart. I'm trying to build a LowFER station but don't have your level of expertise, that's for sure.
It's a great way to learn. I built the first version like 8 years ago and have really just recently had success getting my signal out. I made some changes after making this video that really made the difference. I regularly have people pick up my signal in Tennessee, Mass, and Illinois now. I'm in South Carolina and my previous record was 80 miles to a guy in North Carolina. I will make an update video soon. If you run into any issues, I may be able to help. Also, there is a great group of guys on the LWCA message board that helped me out a lot. Just go to LWCA.net and click on message board if you haven't been there already.
Could you possibly upload the schematic somewhere else? When I try to go to your site it says that it doesn't exist I have found a picture of it on google but it doesn't load in for me. I have been looking around for a simple schematic and you are the only one who explains this project the best. Thanks for making this content!
Try the site again. I just reset it. My server was down. If you still have trouble let me know and ill put it somewhere else.
@@JohnHamerProjects Thank you so much! It works now. I trying to build a transmitter of my own and was needing a simple circuit. Again thank you!
Awesome! Good luck!
Hi, I'm in Turkey. I have some experience in DIY electronics. I want to work on LowFer transmitter and receiver that I can use globally. If you're willing to send me a LowFER audio signal from there, I might be willing to make my receiver design immediately and likewise transmit a signal similar to you. Could working with tesla coils, for example, be a way to achieve this? I live in an apartment with 5 floors. I can use radiators for the heating system of the house as an antenna. Or I can design different antennas. If you are willing to work on this subject, we can do some really fun work.
My transmitter is running all the time right now. It currently only sends CW, no Audio. We are restricted to 1 Watt here in the United States, so I don't know if that's enough to get there. I can look for your signal when you get yours built.
I am not sure about tesla coils. My antenna is not very different from a tesla coil, but without the spark gap oscillator. It sounds like a fun project to experiment with though.
A few months ago I was too interested in this topic, but then I started thinking that it wouldn't make me any money. I am now interested in cryptocurrencies. There is no direct connection to the subject, but a blockchain can be designed, for example, that works with RF signals instead of the internet. This can be very interesting. Maybe this idea will interest you.
Or, a private key with some bitcoin per hour can be broadcast with RF signals. The person who manages to design the receiver receives the bitcoin prize. Such a tap could be a good way to create a worldwide RF network.