If you used two tealight aluminum back to back as the slider, you could build a variable capacitor with a greater range. The two aluminum holders could be held together with either a nut and bolt through the center tr taped together with aluminum or duck tape.
interesting as always, i will say though just in case you hadn't heard and i get the opportunity to finally teach you something: you can actually solder to aluminium. the trick to it though is to keep oxygen away. cover the alu with something like paraffin and scratch away the oxide from the surface before soldering. the paraffin stops it from oxidising again. - i should say.. i've not tried and i've heard it murders iron tips.
Nice one, the classic application of toilet rolls that I've seen so far is as winding body for inductors. You might be able to combine both, winding a coil around the outside and connecting a wire to the slider could give you an adjustable LC network of some kind in one go. Not sure though on the range of frequencies you may cover there.
Thanks Roel. The best approach I think would be to use two toilet rolls and cut a slit down one and tape to end up with a thinner former. Then have two sliding inductors like I did with the crystal set a few videos ago. You might also have some taps for lower inductance options. Main issue is getting sufficient capacitance but you could overcome that by having a few fixed capacitors instead of the variable capacitor.
If you used two tealight aluminum back to back as the slider, you could build a variable capacitor with a greater range. The two aluminum holders could be held together with either a nut and bolt through the center tr taped together with aluminum or duck tape.
Frugal construction redefined :)
interesting as always, i will say though just in case you hadn't heard and i get the opportunity to finally teach you something:
you can actually solder to aluminium. the trick to it though is to keep oxygen away. cover the alu with something like paraffin and scratch away the oxide from the surface before soldering. the paraffin stops it from oxidising again. - i should say.. i've not tried and i've heard it murders iron tips.
I’ve tried it and it does murder iron tips.
Great idea, as always.
Thanks for you continuous contributions to HAMdom.
73 OM . .
nice! i'll have to try that next time i build a radio
Nice one, the classic application of toilet rolls that I've seen so far is as winding body for inductors. You might be able to combine both, winding a coil around the outside and connecting a wire to the slider could give you an adjustable LC network of some kind in one go. Not sure though on the range of frequencies you may cover there.
Thanks Roel. The best approach I think would be to use two toilet rolls and cut a slit down one and tape to end up with a thinner former. Then have two sliding inductors like I did with the crystal set a few videos ago. You might also have some taps for lower inductance options. Main issue is getting sufficient capacitance but you could overcome that by having a few fixed capacitors instead of the variable capacitor.
And Best Thing To Use Is Copper Tape.
You did it,,👍
A few of these in parallel and it becomes usable for lower frequencies, too ;-)
Very nice!
👍👏👏