Hi guys!, im very new when it comes to building circuits, and i don't really know much. so i thought what a better way to learn circuits then to get my feet wet by "just" building a circuit.
so the problem is i don't know what the arrow means. the arrows is going from the C5 to the Inductor L1 (is this a inductor? b/c it doesnt look like a resistor)

does this arrow mean that the C5 connects to the L1 ?

Thx guys

 

Looks like it might be a variable inductor with C5 connected to the "wiper".

 

What does your parts list say it is ? Have you got a parts list for the other components. Capacitor Values, Resistor Values, etc.

 

jwilk13 i dont think its a variable inductor because it only have 2 terminals
stevehow the partslist calls it L1 - 4 turns + 1 jumper

 

I have to agree with jwilk13, Variable Inductor with C5 Connected to the Wiper. Hence it must have 3 Terminals.

 

i think the parts list that i got is wrong, um guys is there any way to connect the c5 to the 2 terminal inductor ?

also what does it mean when it says the jumper

 

It is an inductor (according to the circuit it is labeled L1), with a center tap.... must have to be a home made inductor with a center tap wire for tuning.....

 

It's definitely a variable inductor. The 'wiper' might just be a wire you have to rest on it. Do you have pictures of the inductor you have? Also, was this a kit? Did it come with an inductor, or did you just find an inductor and assume it would work?

You should just be able to "tap" it with a piece of wire. That piece of wire will act as the wiper.

 

It is an inductor (according to the circuit it is labeled L1), with a center tap.... must have to be a home made inductor with a center tap wire for tuning.....

I would agree with the center tap, but in that case it should have a dot or something showing that it's connected permanently to the coil. In this case, however, it's an arrow, signifying it can move. Hence it's a variable inductor, even if you need to physically pick up and move a wire on the coil to tune it.

 

yes it was a kit, it came with the inductor and all the parts necessary for the kit. the inductor that came with the kit was of this kind http://tinyurl.com/d6ojzan

except it has only 4 turns, and the outer is coated with plastic

You should just be able to "tap" it with a piece of wire. That piece of wire will act as the wiper.

can you explain the tapping process please. do i just strip all the plastic from the inductor and connect the jumper from c5 anywhere on the inductor?

 

variable!.................................

 

I would agree with the center tap, but in that case it should have a dot or something showing that it's connected permanently to the coil. In this case, however, it's an arrow, signifying it can move. Hence it's a variable inductor, even if you need to physically pick up and move a wire on the coil to tune it.

Thats pretty much what I meant ..... its not fixed and moveable for tuning purposes..... reminds me of an old Fox hole radio I built as a kid with a toilet paper roll for the core of the inductor which was attached to a razor blade, and a piece of pencil lead was used as a tap, when you slide it across the razor, you can tune it to different stations....

 

Thats pretty much what I meant ..... its not fixed and moveable for tuning purposes..... reminds me of an old Fox hole radio I built as a kid with a toilet paper roll for the core of the inductor which was attached to a razor blade, and a piece of pencil lead was used as a tap, when you slide it across the razor, you can tune it to different stations....

I thought the pencil lead and razor blade acted as the cat-whisker diode....? I always tapped my radios directly on the toilet paper tube coil.

 

Quite unusual to vary the inductance of a tiny RF inductor with a wiper contact. If it was an inductor with a core you could adjust the core position. If it is an air coil (which it probably is) you can adjust it once to tune the circuit (and then solder the C5 wire directly to the coil) but it cannot be meant to constantly being adjusted...

 

Quite unusual to vary the inductance of a tiny RF inductor with a wiper contact. If it was an inductor with a core you could adjust the core position. If it is an air coil (which it probably is) you can adjust it once to tune the circuit (and then solder the C5 wire directly to the coil) but it cannot be meant to constantly being adjusted...

I didn't usually have a tuning cap on mine--it was just the most basic coil and diode. Tuning capacitors were somewhat hard to come by.

 

I thought the pencil lead and razor blade acted as the cat-hair diode....? I always tapped my radios directly on the toilet paper tube coil.

The way I remember it (this was nearly 25 to 30 years ago, yes, I'm THAT old! ), you had to have the blade laying on its side with one side of the circuit connected to it, and have the pencil lead attached to a safety pin, that acted as a spring, so when you press down on the "spring" it slides the lead across the face of the blade..... I don't remember if i tuned it on the blade or the tube coil.... now I am gonna have to look it up, you got me curious

 

The way I remember it (this was nearly 25 to 30 years ago, yes, I'm THAT old! ), you had to have the blade laying on is side with one side of the circuit connected to it, and have the pencil lead attached to a safety pin, that acted as a spring, so when you press down on the "spring" it slides the lead across the face of the blade..... I don't remember if i tuned it on the blade or the tube coil.... now I am gonna have to look it up, you got me curious

Yup, that sounds right. If I remember correctly, the razor blade had to be slightly rusty. The pencil lead had to be moved across the face of the blade in order for it to make contact with just the right rusty spot to create a decent diode. Once there, it would operate correctly and you could tune it by adjusting the antenna tap on the coil. That's how I remember it, anyway. I could, of course, be wrong

 

okay, looked it up >>http://bizarrelabs.com/foxhole.htmhttp://bizarrelabs.com/images/foxhole4.gif , and you were right, it was used in place of a crystal and whisker......

 

Quite unusual to vary the inductance of a tiny RF inductor with a wiper contact. If it was an inductor with a core you could adjust the core position. If it is an air coil (which it probably is) you can adjust it once to tune the circuit (and then solder the C5 wire directly to the coil) but it cannot be meant to constantly being adjusted...

I'd say that is exactly what you do.In other words,it is"adjust on test".
Once you get the best position,you solder it in place.
My guess is that the kit assumes you can get away with connecting C5 to the top of the coil & get away with it.