Thanks for the video. I'm feeling a little grumpy too. My MOSFETs are fakes and every Atmel micro controller I ever bought on eBay has been blacktopped. The more I learn the more fakes and counterfeits I find in my parts bins. To those who think they are getting "good deals" on eBay : many of the components you buy are substandard. Yes most of the components are made in China but up to spec parts are sold by reputable dealers and the fakes, refurbs and factory rejects are being sold to small suppliers in China who then sell them on to the rest of the world as genuine parts. You just don't know what you are really getting.
ok the irf640 are good for 160-80m with reduced performance on 40m. If you get "real" irf520 the have been used reduced power on 6m. 30hhz is about as far as I personally would use 520's. The 540 I think from memory has higher input output capacitance difference, output capacitance was very high if I recall, so performance is poor on frequency just like 640n. Look at the data sheet and check the in/out capacitance. Use the 520 as I guide and you will see the difference with the other specs verses expected performance. Watch out for fakes, I got heaps of duds form ebay. Stick to element 14 as a reference source for original to test against crap china knock offs. good luck. I never normally write this much to subscribers. thanks mate,
Mouser electronics out of texas is a great company to buy from fast shipping and bulk discounts they also sell several brands at different amp ratings.
Hang on a second, (yours may or may not be fake). like many fets we hack to use for other purposes they are switching fets, and not the expensive RF type.. I dont think your 260s would work on very high frequencies beyond 8Mhz anyway (With the exception of the irf510...ect) but would be ok for a 160-80 and perhaps ok for 40 with reduced power. So keep that in mind before you abuse the seller. Just check the data specs for the device for some extra technical explanation. Thanks for your comments and I hope this helps you.
the working frequency is under 500khz, they look different than the ones i normally get and to top things off they over heat at a voltage and current that is far below the maximum rated limit. thank you for double checking my comment.
Hey my pleasure, yes it does indicate they are suspect. Lots of junk being sold I have noticed. I hope you get your money back and get the authentic article and it works out for you. cheers mate.
Hj, are those Diamond SWR/POWER meters just a newer version of the REVEX swr/power meter or are they very different inside? Ps are you in Australia? Thanks in advance. Andrew
But the fakes ones you tried, you just excited with 100mW, and this real ones are putting 1W, 2W. I think it is not fair. Maybe you sould test the mosfets alone, at differents load and frequiencies to see its performance.
Circuit? Circuit? Very interested in trying your design esp. with the feedback you have employed for improving linearity. Interested, too, in 160 meter band operation. 73
Oy! I did see that .. but, I'm vision impaired and thought you might have something easier to view than the other vid showing bits and pieces of the schematic. 73 from W B 5 W P A in Texas Added: I think I can get what I need from the other vid. Thanks.
uploadJ sorry for the delay watch this at the 8 minute mark and you will be guided through the circuit tutorial. It is an iteration on Sevick and Hendge's design. cheers. ua-cam.com/video/9Sl7sbdSpP8/v-deo.html
the problem is that today some chinese sell genuine parts, others not. and it is so hard to tell.. but it is soo expenssive to buy from european source..
Thanks Joshua, I'll try to do more videos. It takes me time to do a useful video, I rather send out a half decent/useful video every month or so, instead of a daily or weekly video that is half baked and questionable of it's worth to the technical community. I am glad you enjoy the channel. Cheers
Hi Derrick, All I did was use standard pcb you can get from ebay or a electronics parts store. I tinned the board and then used a handheld dremel to grind out the tracks. Not the best way but yes it can be done. I hope this helps you. You can draw the tracks with a sharpie and etch it with acid or be flash as do it with a CNC. cheers.
I appreciate the info. I'm planning on building a solid state amp this winter for hf and have alot of spare parts laying around. Thought I might try my hand at it and see what I come up with
Derrick Walls Sounds like a great project, try to keep to a nice layout that is direct, uncomplicated and based from a known design to start with and you should be ok. Double check all voltages and for any shorts prior to power on and start with low levels of supply and voltage and go up in stages and of course "make notes" and keep a diary or a youtube channel to record what you did. let me know how you go mate. cheers. E
Hi, you have to change the power supply from 13,8 to 27 vdc for an real outstanding power out !!!
Dave thanks for your efforts . Do you have a amateur call sign ?
Cheers VK2SS
Thanks for the video. I'm feeling a little grumpy too. My MOSFETs are fakes and every Atmel micro controller I ever bought on eBay has been blacktopped. The more I learn the more fakes and counterfeits I find in my parts bins. To those who think they are getting "good deals" on eBay : many of the components you buy are substandard. Yes most of the components are made in China but up to spec parts are sold by reputable dealers and the fakes, refurbs and factory rejects are being sold to small suppliers in China who then sell them on to the rest of the world as genuine parts. You just don't know what you are really getting.
What frequency would the irf540 be good for or irf640 I bought a box from Amazon with 50pcs and I just want it to work on 160meters
ok the irf640 are good for 160-80m with reduced performance on 40m. If you get "real" irf520 the have been used reduced power on 6m. 30hhz is about as far as I personally would use 520's. The 540 I think from memory has higher input output capacitance difference, output capacitance was very high if I recall, so performance is poor on frequency just like 640n. Look at the data sheet and check the in/out capacitance. Use the 520 as I guide and you will see the difference with the other specs verses expected performance. Watch out for fakes, I got heaps of duds form ebay. Stick to element 14 as a reference source for original to test against crap china knock offs. good luck. I never normally write this much to subscribers. thanks mate,
Why didn't you use a couple of BC108 Transistors instead, great video.
Mouser electronics out of texas is a great company to buy from fast shipping and bulk discounts they also sell several brands at different amp ratings.
thank you for showing this i learned a lesson today and i will watch your other vids for sure...
thanks for doing this series. you helped me confirm that my irfp260s are fake.
Hang on a second, (yours may or may not be fake). like many fets we hack to use for other purposes they are switching fets, and not the expensive RF type.. I dont think your 260s would work on very high frequencies beyond 8Mhz anyway (With the exception of the irf510...ect) but would be ok for a 160-80 and perhaps ok for 40 with reduced power. So keep that in mind before you abuse the seller. Just check the data specs for the device for some extra technical explanation. Thanks for your comments and I hope this helps you.
the working frequency is under 500khz, they look different than the ones i normally get and to top things off they over heat at a voltage and current that is far below the maximum rated limit. thank you for double checking my comment.
Hey my pleasure, yes it does indicate they are suspect. Lots of junk being sold I have noticed. I hope you get your money back and get the authentic article and it works out for you. cheers mate.
thanks, and keep up the good videos. cheers.
Hj, are those Diamond SWR/POWER meters just a newer version of the REVEX swr/power meter or are they very different inside? Ps are you in Australia?
Thanks in advance.
Andrew
Hey there thanks for the video. Its been a while since you posted this. Is there a circuit diagram yet? how much effort to crank this guy up to 200W?
But the fakes ones you tried, you just excited with 100mW, and this real ones are putting 1W, 2W. I think it is not fair. Maybe you sould test the mosfets alone, at differents load and frequiencies to see its performance.
hmoUserr I don't think you were paying attention.
Dear sir nice video. Ive learned lots of things :)
Circuit? Circuit? Very interested in trying your design esp. with the feedback you have employed for improving linearity. Interested, too, in 160 meter band operation. 73
I posted the circuit in the 200W for $20 video and I go through the circuit a bit. I hope that helps you.73
Oy! I did see that .. but, I'm vision impaired and thought you might have something easier to view than the other vid showing bits and pieces of the schematic. 73 from W B 5 W P A in Texas
Added: I think I can get what I need from the other vid. Thanks.
uploadJ sorry for the delay watch this at the 8 minute mark and you will be guided through the circuit tutorial. It is an iteration on Sevick and Hendge's design. cheers. ua-cam.com/video/9Sl7sbdSpP8/v-deo.html
the problem is that today some chinese sell genuine parts, others not. and it is so hard to tell.. but it is soo expenssive to buy from european source..
Love your videos. Very informative as usual. Love the homely feel of your lab bench too. Haha 73s VK3VWS
Thanks Joshua, I'll try to do more videos. It takes me time to do a useful video, I rather send out a half decent/useful video every month or so, instead of a daily or weekly video that is half baked and questionable of it's worth to the technical community. I am glad you enjoy the channel. Cheers
cool i use to buy from the element14 too
Nice review.........
Low pass or band pass filters???
+bvdmedia Did you read the description of this and the following accompanying video???
I have got a bunch of definite knock offs with same specs/performance as original...
what kind of board do you use when building a amplifier like this one?
Hi Derrick, All I did was use standard pcb you can get from ebay or a electronics parts store. I tinned the board and then used a handheld dremel to grind out the tracks. Not the best way but yes it can be done. I hope this helps you. You can draw the tracks with a sharpie and etch it with acid or be flash as do it with a CNC. cheers.
I appreciate the info. I'm planning on building a solid state amp this winter for hf and have alot of spare parts laying around. Thought I might try my hand at it and see what I come up with
Derrick Walls
Sounds like a great project, try to keep to a nice layout that is direct, uncomplicated and based from a known design to start with and you should be ok. Double check all voltages and for any shorts prior to power on and start with low levels of supply and voltage and go up in stages and of course "make notes" and keep a diary or a youtube channel to record what you did. let me know how you go mate. cheers. E
very interesting ...so i subscribed....just a thought "subscribed" has a "scr" in it ....u will understand ..... let me shut up now
Too much camera movement, cant watch this.
Moral of the story?
Repairing is worthless.
Better go for a brand new stuff.