VRF2933 LDMOS 1.7KW HF linear amplifier built by YO6PMX

[@TheBosso4]

The guys also made a 1: 9 transformer from 61 materials. Of course, I did not achieve such power, but the amplifier turned out with amazing linearity! And YO6PMX rights are not heated at all! Thank you YO6PMX!

[@perianmarcel2059]

Hi. I am glad that you have built one too. The amplifier works fine with that 9:1 transformer, as it can be seen on the pa0fri's site. I said from the beginning and I am repeating it, it is not my schematic, I built the amplifier using a schematic from PA0FRI's site. I never said it is linear at 1.7 KW, in the matter of act, I guess it is working in class C at that power... Probably 1 Kw, maybe 1.2 Kw is a decent power where it is working linear.

[@TheBosso4]

Hi Perian! I built an amplifier - concept - model with water cooling by R3KR. See pls kzbin.info/www/bejne/lXW6mZqFbtloe9E Chinese transistors mrfe6vp61k25h were used

[@MM0IMC]

Nice to see you using an old Soviet era doorknob capacitor in that amplifier too.

Hi Marcel, what is the total cost of that amplifier?, its difficult to built? Thanks

[@gratiandoboli6040]

Felicitări Marcel, superb prezentat și realizat amplificatorul !

[@perianmarcel2059]

Merci, Gratian!

[@JamesCutlervk2tim]

Good information on the ferrite output transformer. Just be aware that those transistors will not be linear at 1.7kW O/P. They are rated for 300W each.

[@juststeve7665]

Perian, you can purchase these 61 material ferrite cores from Fair-rite or Pacific Micrometals in California

[@donbeeson7838]

Hello. I like the unit you have buit. Can you give me a schematic and material list so I can build one . Also can i build one using 8 or 12 of the 2933 Transistors?

[@sunrise6091]

super fain - falicitari stimate domn ( de la un pasioant de radio ) poate in viitor si eu radioamator - toate cele bune

[@johnward7619]

Keep up the good work. Great video

[@KF8OD1]

Nice work! Don't be afraid to try something new.

[@perianmarcel2059]

Hello Michael! It is a pleasure and a honor to have this comment on my video. I watched your videos several times, visited your site and got a lot of ideas there. Thank you also for your help with the output filters. Wish you all the best from YO!

[@KF8OD1]

Thank you for your kind words. I hope the filter works well for you. I used it with my first amps for years at 1.5kw, it worked well.

[@km6hvu622]

Looks great thanks for sharing! By any chance did you connect it to a spectrum analyzer to see what the signal looked like? I am just curious to know how much of that power is staying on frequency, I want to build one of these as well. Thanks again.

[@perianmarcel2059]

Hello. No, I never connected the amp to the analyzer, but I have built some output filters using PA0FRi's design. The attenuation of second and third harmonic was ok for those filters. After connecting the filters I have lost between 100 and 200W, so I assume that those were harmonics. Approx 1.5 KW remained on all bands. so i think is ok. As I said before, I do not claim that the amplifier i working in linear mode at those frequencies. I would recommend to use such amplifier for powers around 1Kw - 1.2KW. At 1.7 it is certainly pushed to it's maximum.

[@km6hvu622]

@@perianmarcel2059 Thank you for your reply. I find this extremely interesting and I hope to build one of my own. I really appreciate you taking the time to make this video and sharing.

[@mrkattm]

Very interesting, thanks for sharing, as you know it is not very hard to get a lot of power, question is how linear is it? what is your bandwidth? Can you put it on a spectrum analyzer ?

[@tvnteleviziuneaneamt6409]

Felicitari!!! Deresc si eu unul. Detin 4 tranzistori mrf 150 si un pcb dar fara trafuri. Zi frumoasa!! YO8WTW

[@bob4analog]

Very nice show of your SS amp! Yes, they can easily make the power, especially with today's LDMOS. Of course, the secret to the high power is with the I/O transformers. Indeed KF8OD has made some beautiful amps, both SS and tube. Even tho the SS amps are great, I still like tubes. I hope you don't get too enamored with SS. ;-) Also, nice commentary on the accuracy of your CN-801wattmeter at 2:54. I will get one. 73!

[@perianmarcel2059]

Hello and thank you for your interest! I will not abandon the glowbugs yet, I have a project with GU-5B in mind... Have a nice week-end!

[@YT7RR]

Felicitari Marcel , la reauzire !!

[@perianmarcel2059]

Multumesc! Sedam tri, Nelu!

[@gerardf6ehj77]

Hello Marcel, Utilisez-vous le symétriseur T4 du schéma de PAOFRI dans votre montage ou simplement T3 en filtrage ? Bravo pour votre réalisation. Gérard / F6EHJ

[@zenographie]

Merci beaucoup, Marcel, pour cette édifiante démonstration. Now, we just need your schematic, BOM and assembly instructions :- )))) 73' de Marc f6itu

[@perianmarcel2059]

Bonjour Marc. Comme je discutais avec Eric hier soir, le schema se trouve sur la page de PA0FRI qu'on peut trouver ici: pa0fri.home.xs4all.nl/Lineairs/BLF188%20HF%20amplifier/BLF188%20HF%20versterker.htm. J'ai utilise la version de 23 decembre 2015 sauf la resistance de 33 ohms entre les grilles. Si vous voulez, je pourrais envoyer des photos detaillees par mail. 73 et bonne journee!

[@dave858man2]

very impressive build. what is the frequency range of those LDMOS? I am also interested in your power supply, do you have a manufacturer and model #?

[@perianmarcel2059]

The transistor is rated at 150 MHz in its datasheet. My amplifier has been tested between 3,5MHZ and 29 MHz. The power supply is 50V 50A built by a romanian company (Antrice). Those power supplies are widely used in mobile telecommunication companies.

[@Paul_VK3HN]

Cannot find anything about your power supply, can you post a link please?

[@istvanszabo8698]

What frequency range can you use your amp? 1.8-50 MHz?

[@ИванМирный-е6э]

Учитывая 61 материал, думаю 20-50 МГц

[@Py1axRADIOAMADORISMOSEMSTRESS]

Very good i need onewith 500w you can make for me and idea about cost ?

[@perianmarcel2059]

Hello. I do not build for sale, but there is a russian guy on Ebay who does. Send me an email and I will give you the link. My mail is on qrz.com. 73!

[@edsonpereira5882]

hello I would like to know the reference of these ferrites that goes in the assembly of the transformer. where can I find

[@drewbyronmeadows2208]

Very nice amplifier, I am thinking of building something similar, really glad to see that it is possible to make such a robust solid state amp. How does it perform?

[@perianmarcel2059]

Hello. Flawless until now.

[@OlympusHeavyCavalry]

You sound a little like Slow Poke Rodríguez. Cheers for the video bud :-)

[@tlrptg]

felicitari pentru constructie !! incearca sa montezi senzorul de temperatura / bias pe placa de cupru, intre MOSurile din mijloc. 73!

[@perianmarcel2059]

MUltumesc! In ceea ce priveste senzorul, conductibilitatea termica a ansamblului e foarte buna, nu am reusit sa il supraincalzesc niciodata pana acum si nici diferente majore de temperatura nu am sesizat. E mai usor de ingropat in aluminiu decat in cupru... Am facut intre timp inca vreo 3 exemplare, pentru prieteni, si nici acelea nu se incalzesc semnificativ, chiar pleaca ok regulatorul de temperatura...

[@tlrptg]

sa mai faci te rog un test: pune ansamblul amplificatorului la frigider, la 4 grade, cateva ore. Dupa aia, alimenteaza ampliful, cu sarcina artificiala la iesire, si verifica curentul de repaus al MOSurilor. Tine ampliful alimentat, fara excitatie, si vezi cat creste curentul de repaus, si daca se stabilizeaza la o anumita valoare, si daca valoarea e cea recomandata pentru VRF2933. E un proces de durata, dar te scapa de cheltuieli neprevazute. Timpul alocat testului sa nu fie mai mic de 4-5 ore.

[@chriswesney]

What are you using for your output filtering?

[@perianmarcel2059]

Nothing for now. The amplifier is not on the antenna in a full functional assembly yet. I am intending to use a set of filters described by KF8OD (thanks again). In this moment I am using the amplifier in 20m only with only one filter, described by PA0FRI here: pa0fri.home.xs4all.nl/Lineairs/BLF188%20HF%20amplifier/BLF188%20HF%20versterker.htm The 20m filter has 2 coils of 560 nH each, on T130-2 toroid core and 3 silver mica capacitors (150pF-330pF-150pF). It has been tested on spectrum analyser and it is suppressing very efficiently the 3-rd harmonic and quite ok the second.

[@paulocendegui_ce3vna]

hi, a question, the ptt of the amplifier is activated with the rf that enters from the radio, is that correct?

[@perianmarcel2059]

Hello. Yes, this is correct. I chose this method knowing that there are different commands for the linear from different transceivers (simple relays in older transceivers, low level logic commands from newer transceivers) so the "rf vox" is somehow "universal" command mode. The same can be seen in most of the RM Italy ham amplifiers (HLA 300 by ex.).

[@achmadanangaswanto2726]

Can you please give me the schematic of this amplifier? Thank you,

[@skylabby]

Do you have a How-to-Video or circuit diagram you can share or point me to? (8P4DG)

[@markpedretti3765]

Very good!!! Where to buy only the toroids? 73Mark PY2NA.

[@perianmarcel2059]

Hello. I bought them at www.mouser.com, ref No 623-2661102002

[@ИванМирный-е6э]

Откуда 1.7 кВт? Максимум 1.2, даташит не позволяет

[@dwarslopers]

Well done! Thanks for sharing!

[@rogeronslow1498]

Where did you get the RT4/F power supply?

[@perianmarcel2059]

Hello. The power supplies are salvaged from old mobile telecommunication equipment replaced for upgrade. They can be found on Ebay or on local ham internet sites sometimes. Any 50 - 54V 50A will do it.

[@adonirom12]

Hello Perian , do you make amplifier board like this complete for sale minus vrf 2933 for sale? I would like 2 complete boards. Also how many amps does this unit draw? I can give you email if you like.

[@perianmarcel2059]

Hello and thank you for your interest, but these projects are not for sale, I have no time to build for sale. They are just for educational and experimental purpose and they are under continuous improvement :) . Have a nice day! Marcel

[@youtubeaccount931]

Nice!

[@eduardogarciamontesdeoca5935]

I really enjoy your video... thanks!!

[@perianmarcel2059]

Thank you!

[@traian1782]

Nice amplifier. GL & 73!

[@petrok1rp254]

How the RX/TX fast switching is solved please?

[@perianmarcel2059]

Hello. I don't understand what "fast" means. The switching is done using an old russian hardware method. The output relay (antenna relay) has two contacts. One is used to switch the RF and the other one is commanding the input relay (12V DC), so, there is impossible to start the amplifier before the antenna is coupled...

[@petrok1rp254]

michaelscoofield I mean QSK switching in between TX and RX. If there is relay then its too slow to listenning in between own dots and dashes on CW. Anycase its great job. Congrats. Petr

[@RADIOREYJESUSOAXACAFM]

hola una pregunata para 27 mhz funciona con cuantos wuast de entrada

[@fnordist]

1.21 Jiggawatts

[@neodiy]

great video and btw you speak like paolo freire ;) very cute accent

[@ta1cbo]

Hello Perian I fallow all your amplifier congrulations! I learning lot of things and pratic ideas your amplifier material61 amazing idea but I did not found this ferrite if its possible write here company code please 73

[@perianmarcel2059]

eu.mouser.com/ProductDetail/Fair-Rite/2661102002?qs=%2Fha2pyFadujJ1Lpn9LJ%2Fdpa%252BD2gpa8KvGDyYeOghdJat9XRIHYfE%2FQ%3D%3D

[@ta1cbo]

Thank you for your answer

[@rahulraj1865]

Can you give me the circuit of the amp

[@unclequack5445]

1.7 KW from a 4 pill?

[@defaultuser000]

The VRF2933 is a 50 volt VDMOS device that is capable of 300W per FET up to 150MHz. According to the datasheet, you can push them much harder. I'm sure the linearity will suffer, but I've heard of people running 4 of these at 1.2-1.5KW all day long with no issues. They also make a VRF2944 that does 400W per FET. Both handle up to a 70:1 SWR also. Microsemi has made some seriously impressive devices using the VDMOS technology.

[@bangkithutajulu8851]

wow awesome

[@black2999ro]

wow !!! bravo !!! 73 de YO8SCT

[@perianmarcel2059]

Multumesc. Mai urmeaza filtrele...

[@foofoomatic]

FYI: These are VDMOS parts, not LDMOS parts. See Dick Frey's (K4XU) video from Microsemi... fun watch. kzbin.info/www/bejne/mH6opHh3idqXna8 Disclaimer: I am a Microsemi employee.

[@perianmarcel2059]

Yes, you are right. And thanks for the video, really impressive to obtain 1,2 KW from 2 transistors.

[@RADIOREYJESUSOAXACAFM]

hola puedo usarlo para 27 mhz

[@perianmarcel2059]

Hello. Yes, it can operate in the 11m band, but it is illegal there. Maximum accepted power in CB is 5W as far as I know...

[@RADIOREYJESUSOAXACAFM]

If you observe if you use the power that you want, there is no problem of how much it costs price for the 11 meter band

[@razvanneagu6860]

Buna Marcel ai un e-mail unde poti fi contactat private ? Multumesc mult . Raz

[@perianmarcel2059]

indicativul meu la gmail

[@razvanneagu6860]

@@perianmarcel2059 Buna Marcel multumesc pentru raspunsul rapid dat. La rindul meu sint in construirea unui linear amplifier cu 4xSD2943 dar sint intr-un impas si nu stiu cumm sa il setez pot sa trimit mai multe informatii daca ai timpul necesar. Mutumesc anticipat 73! VA7ZAR

[@DanMagers-lj7mq]

Not an accurate power output as it is rich in harmonics. Let’s see the power output at the fundamental on a spectrum analyzer or after a proper LP filter.

[@murlik1]

Foarte interesant 73 VE3BDE

[@julianjames4519]

50V Power Supply, 1:9 Output Transformer and 1,7 KW......it is mismatch.

[@valerygodyak79]

there is no replay

[@perianmarcel2059]

Right! God moved my needles!

[@perianmarcel2059]

@ , why do you assume an efficiency below 50%? The total dissipated power of an VRF2933 is 648 W www.microsemi.com/document-portal/doc_download/77339-vrf2933-mp-datasheet . If we assume a 50% efficiency (which is the worst i've ever seen!) , 1300 W is an acceptable power for 4 pills. Ok, the 2nd and third harmonic is about 200W (measured that). Can I have 52% efficiency? :) Some says one can acheive even 60% efficiency in class AB... www.electronics-tutorials.ws/amplifier/amplifier-classes.html Of course that the amplifier cannot be putted on the air without output low-pass filters, as i said, after filtering I have lost about 200W at the output.

[@red5media_gr]

@@perianmarcel2059 ...just because you use a specific rf class it doesn't mean you have that efficiency. for that output power of VRF2933 your IMD will be much worst for SSB use. in push-pull topology, the even harmonics are canceled, only odd will be present and strong (cause no LPF filter), which will count in fake watt output. 50V, 1.7Kw will give an impedance of 2.8 ohm, how a 1:9 transformer would work???.

[@baadikarim]

Pls mail

[@crobulari2328]

Bird Thru line does not always tell the truth. !!. B Careful.