I am going to try another build with SMD if i can get the right values. i did not remove the trimmer capacitor in my build, so i can still do frequency compensation .
You have 16 banks of 5w resistors. That makes 80watt not 240w. You would have to have all 48 resistors in parallel to get to 240w. Plus they are all touching each other. You need a gap between all the resistors for the oil to work at dissipating extra power.
I did not. that is what Lester claimed in his build video, and that was suppose to be "peak-envelope-power" SSB and intermittently at that. I merely reverse engineered is so people could build it. Lester never told what the resisters were, how many or what wattage. I used 48 270 ohm, 5 watt resistors in series-parallel. I needed something to test with that would hold at least 100 watts straight power, and i figured this would do the trick.
Great video - I'm in this position now. 1 question though since I'm old as well and its hard to decipher the color bands - #1 and #2 Resistors are both 9M.. is the third resistor going to the DC lead a 4.7M? Thanks.
Yes. They should all total up to 15 meg, including the resistor in the scope. So you would have a 9 meg + a 4.7 meg + the 1.5 meg inside the scope for a total of 15 meg. It basically creates a voltage divider circuit to get the correct voltage reading on the scope display.
thanks i will be vary interested in them. I liked the boxes that you made vary nice. I order the parts to do the dummy load I've been needing one for a bit but just didn't want to fork out the cash to buy one. Thanks@@rusty1187
You did a great job, I got the can at ace, got resistors on e- bay, and one sided circuit board on e-bay! Mine were 3 watts so it should do legal power or a little less. My three tube 811 will not do 1 kw any way. Very sad nothing made in the USA! Our politicians have sold our job’s away to China. What a shame. I am glad I am old! JohnBoyUtah KJ7TBR 🇺🇸😎📡🎙🇺🇸🇺🇸🇺🇸🇺🇸🇺🇸🇺🇸
This is suppose to handle 2500 watts Peak Envelope Power.... I.E. sideband. And i'm thinking probably not continuous! I bought a lot of fifty 5 watt, 270 ohm resistors for my build. got them off EBAY. It took 48 resistors i believe.Getting an empty metal paint can was difficult too. www.ebay.com/itm/311310282887?hash=item487b89f087:g:~qQAAOSw435iPI3r&amdata=enc%3AAQAHAAAA8JkApe8m76fsf0jGhgVzX%2Bp8byezzq%2BWKXKyKftPLzVAV0Un%2FeZsn4MNhLUfU41Wxt%2Fp3VaPAaIk%2BskQKPLBkAphCDriHMgrE4Vx9aQnOM7blxXjFDGJDLlMB7Qo0ZwHxmth6a%2ByDUhHvkot75rQiwL0EcC1hg5Lzrrq9Q1wUc33%2FBGRjCduN8voxocrnwMvhSi6DNMXuYY3F3oBua4YISriU6jU%2BuMg1FXGptFxxR6fimTJBtKxJnkdnwbeZU%2B%2B46Ts1n0NDteIoau4mCmmcvKvz8xoaIaLypbpEvpBEcAvBsAy9gJeEEMH8y0Zn31pjQ%3D%3D%7Ctkp%3ABFBMjOysjf9g
Lester’s stuff is way over priced! I was disappointed that he did not give resistor values, but it is reverse engineered real easy! Yours is a good video. I was told that the relief valve is important in the lid ! Like the Heath Kit version! JohnBoyUtah KJ7TBR 🇺🇸🇺🇸🇺🇸😎🎙📡
Just for future reference, mineral oil will not go rancid like cooking oil. On a separate note, most Ace Hardware's stock new empty Gallon Paint Cans for $4.99 each.
"Rancid" cooking oil has a smell, no doubt. But it still cools just the same. You may wish to change it out every 18 months, but it is certainly cheaper than mineral oil !!
