Ferite loopstick antenna from switching power supply transformers

[@coffeecuppepsi]

Oh wow that's interesting. I always assumed the core would be too losy

[@ingussilins6330]

Losy is a interference suppresion ferrite rings. I try it and bad work ( low Q ). All impulse transformers is ok.

[@ВасилийТёркин-г3м]

I also thought so, that for standard ferrites with a permeability of 2000+ at frequencies of 500-1700 kHz, losses will greatly affect the quality factor and the sensitivity will be too low. But I was wrong. After all, the main secret of success is don’t be lazy, but take it and do it! I want to try to make such a receiver too. Only I will position the core halves differently to get more length.

[@radiofun232]

Well done! Good invention.

[@MAKSMIT-ME]

Я использовал трансформаторы от экономных ламп , и они тоже работали.

[@ВасилийТёркин-г3м]

Wow, you finally did it!!! And the sensitivity is surprisingly good. I think if a larger core is used there, for example from an ATX power supply, then the sensitivity will be even higher. It's a pity that the diagram remained unshown. Did you use a MOSFET in the input stage there?

[@ingussilins6330]

This radio use JFET input stage ( 2N3819 transistor ).

[@ingussilins6330]

About ferrite loopstick antenna: I wind up about 50 turns and measure inductance ( about 350uH ). Next I remove turns and measure inductance ( need about 200...160uH ).

[@ВасилийТёркин-г3м]

@@ingussilins6330 Cool! I just grabbed the first transformer I came across from an ATX PSU and welded it in boiling water. When it finally came apart, it turned out that I had won bingo! Its core turned out to be EI type and a great idea came to me. I broke off the side pieces from the E halve and glued them to the I part. The result was a gorgeous flat rod measuring 8cm long! I hurried and wound 80 turns without preliminary calculations. As a result, I greatly missed the mark with the inductance, which turned out to be more than 1600 μH. Well, we’ll have to redo it, but the main thing is that there is already something to redo. :)

[@ingussilins6330]

@@ВасилийТёркин-г3м Thanks, I will try it ( transformer from PC power supply ). 2mH inductance - this is for long wave radio band.

[@ВасилийТёркин-г3м]

@@ingussilins6330 It's a pity that JFET. As I said earlier, a huge green toad is pressuring me not to use such expensive parts on a super cheap project. I'm going to try using cheap general purpose MOSFETs like 2N7000 or similar. If such a MOSFET does not work, then I will use an emitter follower on a transistor with a high beta and an increased load resistance. Well, then, maybe I’ll even convert it into a super heterodyne receiver with a ceramic IF filter.

[@edvanedvandasilva6878]

Adorei

[@frequencywatchers]

Just fiy, This Is Not How Its Made Video :D But cool, I Worked On Similar Project Today

[@ВасилийТёркин-г3м]

I, too, will now leave everything and go make such a receiver. The variable capacitor has already been found. The audio amplifier is soldered. All that remains is to make the same magnetic antenna. :)

[@ДокторХайдер-г8ь]

👍