Publikované v: Technique
Hello,
I would need help regarding winding coils. When I have written in the scheme for example: L1 - 20 turns on a 5mm core, L2 - 5 turns on L1.
In practice, this means that I will wind L1, that is, those 20 turns, and then I will wind L2 next to the winding of L1 (so as if I continue in the winding of L1) or I wind L2 in the second layer on L1? Thank you for the advice.
You provide the following information: L1 – 20 threads on a 5mm bone, L2 - 5 threads on L1. In practice, this means that you wind L1, that is, the 20 turns, throw a strip of insulator (paper, foil) on it and you wind L2 in the second layer on L1, if you continued to wind L1, it would be, for example, a coil with a branch, it would be stated in the description of winding, but it does not have to be a rule depending on the connection of the coils
I forgot to mention that the wire diameters are different. So in that case it probably wouldn't be a coil with branches. Anyway, it will probably be as you say, and I have already done so, I marked them with thin paper and put them on. And even when I mention those wires, one question comes to mind. The CuL designation is clear to me. But I found the designation CuT and CuY respectively, but it should probably be the same. Can you advise me what the wires are? Specifically, I have such a wire prescribed for the extraction of a two-hole core. Thanks
Copper wire with green insulation - used, for example, for winding ferrite antennas on AM - which we do not have to laboriously scrape, just heat with a soldering iron with tin and we can immediately solder.
CUY - this should be a CU conductor with PVC insulation.
Daniel
My experience when soldering such conductors, I use the medicine 'Acylpyrin'. I place the conductor on the tablet, a warm soldering iron, and tin. It solders excellently.
Stano.
Thanks for the advice. So regarding those wires and insulation, if I use CuL instead of CuT, nothing should happen. I assume the insulation is there to prevent the varnished wire from wearing through somewhere and shorting out. So with sufficient attention, it should ultimately not matter. Or is there something else in it?
I've heard about that Acylpyrin but haven't tried it - I'll give it a shot 🙂
And another thing. As I'm winding those coils, I came across one in a ferrite cup that I don't have. The material is N22 and the diameter is 20. I can't find that diameter 20 anywhere, and especially not in material N22.
The closest diameters I found are either 18 or 22 (at http://www.ferity.czbut again different materials. So there are two problems. What other material could be used? It is for the nf filter in the receiver so it shouldn't be that critical. And if I use a different diameter, how do I calculate the inductance? I found some pages for calculating L but without a core. And I don't know if L is calculated the same for cups as it is for classic rod cores (I assume probably not). There might also be a possibility to change the inductance of the coil but since this nf filter is made up of this coil and two Cs, it would also be necessary to change those capacitances and I don't know how to do that. If you can, please help 🙂 I also have one very simple solution in mind - if someone at home has a cup N22 diameter 20, I would buy it 🙂 teda netuším že ako na to. Ak môžte, pomôžte 🙂 Napadá ma ešte jedno veľmi jednoduché riešenie – keby niekto doma máte hrnček N22 priemer 20 tak by som ho odkúpil 🙂
Thank you
If you know what inductance you need, use a mug core you can find, wind around 10 or 20 turns with the appropriate wire there and measure its inductance - well, then it's simple, no, roughly: put the required inductance in the ratio to the measured one and multiply that by the number of turns you experimentally wound - and from that you get roughly the required number of turns - so far this principle has worked for me. Fingers crossed...., Daniel.
Well, that's exactly the problem, that I don't know what the inductance should be. I only have what core, what wire and how many turns written. It could be solved by calculating it, only the problem is that I don't know how 😥
For the calculation of inductance with a core, a simple formula applies
N = √(L/k) where √ is used as a substitute symbol for the square root, k = AL . 10 to the -3 Al = also the inductance of one turn in nH (uH . 10 to the -3)
common blue core 4 mm from Pramet Šumperk for a 5mm skeleton had k = 0.0073. The value of Al is usually stated for cup cores
If the coil L2 is on L1, it is usually placed at the cold (grounded) end of L1
VY 73 Miro OM3CU
.. but it can't be determined from the schematic - regarding that resonant circuit - where you have that coil - where it should resonate? - throw the schematic here - if possible, hi.
Daniel
I have already found the calculation of that inductance in the book Radio Technology in a Nutshell but thank you. The problem is that I don't know AL. It is not in the schematic, it only states the diameter 20mm and material N22. Dano, regarding that resonance, it might work, here is the schematic: http://ulozto.sk/xhDhcXk/trx-jpg I'm sorry for posting it like this but I don't know how to insert an image. This is about L5 and L6. I also thought that I could completely remove the nf filter (that is, L5, L6, and C15, C16) and replace it with another filter, like this one: https://CQ.sk/modules.php?name=News&file=article&sid=278
What do you think about that?[/img]
So I looked at that diagram - it's a CW filter 800 Hz - and with capacitors C15 and C16 you can change the frequency according to your ear, yeah and the CW filter should be wound bifilar - so you already know the frequency and you can proceed as I wrote before, Hi, 73, OM1DS, Daniel
Hello, according to the scheme I think you are making TRX Kolibrik, on my website it is described how I used to do it and I made a completely different RX, if you want take a look. It works better than the one with MAA661, there is also a pot core in the NF path. The material and AL constant are usually indicated on the cores and when you know the number of turns you can calculate the inductance. So in my receiver, L7 is 300mH and with a capacitor of 150nF it resonates at about 750Hz - you calculate according to Thompson's formula. Here is TRX http://www.QSL.net/om3cug/trx80m1/trx80m1.htm and pages http://www.QSL.net/om3cug/ by the way, I think that material is H22 and not N22, pots were made from material H and that transformer in the original RX of Kolibrik is for NF frequencies and there you need hundreds of mH to units of Henry so take another look at that AR. Please send me your email address to om3cug@pobox.sk I still have some calculations of coils, toroids, and pots with poke so I will send it to you if you are interested. It will help you. For now, VY 73 Igor OM3CUG