Just built a similar amp using the MFRX1K80H. The board design is somewhat similar from DXWORLD-e and the power going is 57v DC at 30 Amps. The output is 1KW. A 7-band Low-Pass Filter was included in this design. The transformers in this design are a 1:9 coaxial transmission line type of transformer from the LDMOS Drain Pins and then that is fed into a 1:1 coaxial transformer for the final output stage
Been playing with this design for sometime with pretty good results especially with a Pi LPF to reduce harmonics. However I was never able to get the 2 devices to work good with 1 xformer. Great video.
Is there somewhere I can find a gerber file library? These boards would only cost a few dollars to have made but everywhere i see pre made boards they are $70+ unpopulated. For $100 I can get one populated with everything bar the LDMOS. nice work on the transformer. I also considered this but with brass tubes. What is the difference / best between copper and brass in the transformer design? Thanks. Another question about tuning for different bands. I see people add low pass filter boards for various bands but if you only want to mono-band what is the equivalent part to tune. It is simply an air choke and capacitor mounted directly to the LDMOS board or you always need to add an external bandpass filter if Mono-banding?
Very nice! can't wait to do a build with one of these bad boys. Watched it when you released it but don't think I commented on it....Man I need to get my butt over there and visit you man and catch up soon. I love the growth you have made :) LOVE IT!
P : 60V X 30A = 1800W, RF power : 1250W, so it was 1250/1800 = 69% efficiency? Is it correct? And so about 550W is dissipated as heat? So will need large heatsink and fan
What modifications have been made to this board since the release? Wasn’t this the board that no one had any luck with? Seems it presented lots of trash on the second, third, fourth ect in real life applications.
What kind of power supply you used to get 60V ? I am also using MRFX1K80 for my homebrew HF amplifier but just got 800W from LPF output with 53V power supply. Is it possible to get 1.5kW from LPF output with 65V on 160m band ？ Thank you.
LPFs for these kind of amps are _NOT_ an optional extra. Your bird is reading most likely a square wave. It will not be accurate under these conditions, and will 'overread' like crazy. This is probably an 800W amp. More like 600 if you want good linearity.@@rfmanchannel6915
This amplifier is class AB Bias. The Negative Temp Coefficient (−2 mV/°C) of the Zener diode provides temperature compensation. I have openings in my PC board so you can place the body of the diode directly on the copper heat spreader. Regards
I have built a GS35B on 6m. The LDMOS amp is far less work. The gain on these things is crazy. Used 188xr on 6m, 2m, and the FM band. They are bulletproof.
This output power is meaningless without running it through an appropriate low pass filter for each band. Your "Bird watts" show all the garbage harmonics, as well as the fundamental. LPFs are _NOT_ an optional extra for testing or using these amps. Show how many "Bird Watts" you have AFTER an appropriate LPF. You need to also show the waveform on a scope, as measured across the dummy load. If it is not a pure sine-wave, even the mighty Bird readings are plain inaccurate. NONE OF YOUR VIDEOS SHOW THE POWER UNDER CORRECT USAGE. Nor do they show linearity and IMD. Without this setup and these readings, your measurements mean nothing. Please do it properly, using a cleaned up sine wave output and a 2-tone IMD test, You know that some CB guy who buys an amp from you will NOT put an LPF after it? So sell them as part of the amplifier. Anything else is irresponsible.
I will and many others will Report you and Record all your Videos you have Lied in have Fun make us Lots of Money for We will be Coming for Everything you own. and I Welcome anyone Else who wants too join my Class Action Law suit on this Scammer.
Nice build. I'd like to see what the Bird reads once you've cleaned up the signals with a low pass filter.
Just built a similar amp using the MFRX1K80H. The board design is somewhat similar from DXWORLD-e and the power going is 57v DC at 30 Amps. The output is 1KW. A 7-band Low-Pass Filter was included in this design. The transformers in this design are a 1:9 coaxial transmission line type of transformer from the LDMOS Drain Pins and then that is fed into a 1:1 coaxial transformer for the final output stage
That transformer looks good for home made, professional job! The crimp looks clean!
Thanks for your comments. RF Man
How do I get one for my big rig
Its amazing the power these small amps put out.
Been playing with this design for sometime with pretty good results especially with a Pi LPF to reduce harmonics. However I was never able to get the 2 devices to work good with 1 xformer. Great video.
Is there somewhere I can find a gerber file library? These boards would only cost a few dollars to have made but everywhere i see pre made boards they are $70+ unpopulated.
For $100 I can get one populated with everything bar the LDMOS.
nice work on the transformer. I also considered this but with brass tubes. What is the difference / best between copper and brass in the transformer design? Thanks.
Another question about tuning for different bands. I see people add low pass filter boards for various bands but if you only want to mono-band what is the equivalent part to tune. It is simply an air choke and capacitor mounted directly to the LDMOS board or you always need to add an external bandpass filter if Mono-banding?
Very nice! can't wait to do a build with one of these bad boys. Watched it when you released it but don't think I commented on it....Man I need to get my butt over there and visit you man and catch up soon. I love the growth you have made :) LOVE IT!
Hey Tom, thanks for your comments! 73
P : 60V X 30A = 1800W, RF power : 1250W, so it was 1250/1800 = 69% efficiency? Is it correct? And so about 550W is dissipated as heat? So will need large heatsink and fan
Thats A Bad MoFo, I Want One!
Have a most awesome evening!
Thanks for your comments! RF Man
How do you adjust the optimization for the upper part of the band?
What modifications have been made to this board since the release? Wasn’t this the board that no one had any luck with? Seems it presented lots of trash on the second, third, fourth ect in real life applications.
Gatekeeper brought me here, great content with n your channel sir. 73
How that plays on 6m?
very good project..
The amplifier can operate 100% heavy duty. For example, a 48-hour contest delivering maximum power?
Couple of questions…
Will it operate on 160m and at what efficiency?
Where can the copper heat spreader be obtained?
Thanks
Have found 6mm copper used for industrial electrical switch boards. Make sure its flat as mating to the aluminium is essential. Good luck.
Can you buy the ferrite at ASAP give me a link to the website
Wow, look at that pill! Gonna really get some swing! 10-4 Good buddy.
What kind of power supply you used to get 60V ? I am also using MRFX1K80 for my homebrew HF amplifier but just got 800W from LPF output with 53V power supply. Is it possible to get 1.5kW from LPF output with 65V on 160m band ？ Thank you.
checkout DXWORLD-e
Show the spectrum on your device
Like all pallets, you will need to add a LPF for FCC compliance.
LPFs for these kind of amps are _NOT_ an optional extra. Your bird is reading most likely a square wave. It will not be accurate under these conditions, and will 'overread' like crazy. This is probably an 800W amp. More like 600 if you want good linearity.@@rfmanchannel6915
I've been looking for the fair I can you give me a link please ASAP thank you
How is the transistor mounted to the heat spreader?
I drill and tap the copper heat spreader and use high quality thermal compound.
I would reconsider that option. Soldering down to the copper provides better heat dissipation and less heat in the high current path.
Hello, how does a Zener regulate by temp, when it is only soldered to the board.
What class is this biased in, AB? Sorry, Ldmos is Chineasium to me
This amplifier is class AB Bias. The Negative Temp Coefficient (−2 mV/°C) of the Zener diode provides temperature compensation. I have openings in my PC board so you can place the body of the diode directly on the copper heat spreader. Regards
@@rfmanchannel6915 Very cool!!!!
Thanks for the reply😃
Amazing .nice piece .
Hey Jeff, thanks for your feedback!!
What was the current draw?
Peak amp draw not dead key
Also how much driver power was radios at
Nice video, thanks.
ldmos, and im still chasing glass tubles xD
I have built a GS35B on 6m. The LDMOS amp is far less work. The gain on these things is crazy. Used 188xr on 6m, 2m, and the FM band. They are bulletproof.
Sir I'm form India plz 30 km FM tanismitter...rf circuit diagram...send me..plz sir..comon parts
What is the frequency in MHz? Regards
comercial sets available in India don't make own which purpose do you want
This output power is meaningless without running it through an appropriate low pass filter for each band. Your "Bird watts" show all the garbage harmonics, as well as the fundamental. LPFs are _NOT_ an optional extra for testing or using these amps. Show how many "Bird Watts" you have AFTER an appropriate LPF. You need to also show the waveform on a scope, as measured across the dummy load. If it is not a pure sine-wave, even the mighty Bird readings are plain inaccurate. NONE OF YOUR VIDEOS SHOW THE POWER UNDER CORRECT USAGE. Nor do they show linearity and IMD. Without this setup and these readings, your measurements mean nothing. Please do it properly, using a cleaned up sine wave output and a 2-tone IMD test, You know that some CB guy who buys an amp from you will NOT put an LPF after it? So sell them as part of the amplifier. Anything else is irresponsible.
🇧🇷🇧🇷🇧🇷👍👍👍
Thanks!
I will and many others will Report you and Record all your Videos you have Lied in have Fun make us Lots of Money for We will be Coming for Everything you own. and I Welcome anyone Else who wants too join my Class Action Law suit on this Scammer.
what happened? This guys is really professional, he does not seemd to be a scammer.
I’m interested in buying a 600-ish watt PEP LDMOS amp with enclosure and fan. Are you currently building? -WA4SUP