I need help with idx pro silverdog red pcb!!

[chiuino]

THANK YOU very much
You've been really help for me! Thanks again

Andrea.

[Qiaozhi]

The problem is why with 110inner radius 0.7mm wire for 35turns the coilcalc gave me 0.721mH inductance when other people says .587mH with the same wire and turns and coil diameter!
Thanks Qiaozhi

P.s. Only if i reduce at 31 turns i approach .571mH but this value not equal to .587 where is the truth....

For a 270mm diameter DD coil, you have two diameters for each D-shape. To get an approximation of the radius for an equivalent circular coil, the calculation is (270 + (270 / 2)) / 4 = 101.25mm. Not 110mm. With 35 turns of 0.7mm wire, the inductance is calculated as 652uH.

Obviously the inductance calculation is not an exact science, but it does get you close to the correct value. However, to paraphrase Charles Babbage ... "rubbish in, rubbish out".

[chiuino]

Oky doky

Thx gaby_sult

[gaby_sult]

The problem is why with 110inner radius 0.7mm wire for 35turns the coilcalc gave me 0.721mH inductance when other people says .587mH with the same wire and turns and coil diameter!
Thanks Qiaozhi

read this.IDX_Concentric_coil.pdf

[chiuino]

The problem is why with 110inner radius 0.7mm wire for 35turns the coilcalc gave me 0.721mH inductance when other people says .587mH with the same wire and turns and coil diameter!
Thanks Qiaozhi

P.s. Only if i reduce at 31 turns i approach .571mH but this value not equal to .587 where is the truth....

[Qiaozhi]

Then just use D_Coil_as_Circ_Diam , in a Coil Calculator to get Inductance.

If you're putting the coil diameter into the Coil Calculator, then that's your problem. You should be entering the radius.

[chiuino]

Sorry for insistence but i need info before making coils
Someone can delete my doubt with a answer?

What is the right parameter in coil calcualtor for making 27DD coil?

In a discussion i had read this:

Actually, you can do a simple calculation:
D_Coil_Half_Circumference = (D_Coil_Diameter + PI * C_Coil_Diam / 2)
D_Coil_as_Circle_Diam = (D_Coil_Half_Circumf / PI)
Then just use D_Coil_as_Circ_Diam , in a Coil Calculator to get Inductance.

So, it seems that the D Coil Half as a Full Circle Diameter is about :
D_Coil_Half_as_Circ_Diam = (0.82 * D_Coil_Full_Diam)

So:
27cm DD Coil Diam => 22cm Diam as Full Circle <----someone confirm that this is correct?
13.5cm DD Diam => 11cm Diam
21cm DD Diam => 17cm Diam
41cm DD Diam => 33.5cm Diam
ecc. ecc.

All this because the data that is reported on the forum about 27DD coil with 0.7mm wire on calculator with 35 winding not correspond at 0.587 mH
IMG_20170227_145953.jpg

Thx to all!

[Wahyu]

Hi CDI, i use lipo bat 3cell , at full charge 12.6v, still hot without sound.
Hi my friend gaby, thank for pcb

[chiuino]

Some info before making the coils....
What is the right parameter in coil calcualtor for making 27DD coil?

In a discussion i had read this:

Actually, you can do a simple calculation:
D_Coil_Half_Circumference = (D_Coil_Diameter + PI * C_Coil_Diam / 2)
D_Coil_as_Circle_Diam = (D_Coil_Half_Circumf / PI)
Then just use D_Coil_as_Circ_Diam , in a Coil Calculator to get Inductance.

So, it seems that the D Coil Half as a Full Circle Diameter is about :
D_Coil_Half_as_Circ_Diam = (0.82 * D_Coil_Full_Diam)

So:
27cm DD Coil Diam => 22cm Diam as Full Circle <----someone confirm that this is correct?
13.5cm DD Diam => 11cm Diam
21cm DD Diam => 17cm Diam
41cm DD Diam => 33.5cm Diam
ecc. ecc.

All this because the data that is reported on the forum about 27DD coil with 0.7mm wire on calculator with 35 winding not correspond at 0.587 mH


Thx in advance!

[CDI]

One stupid question: but, how much voltage u have on battery? I ask u this cause last time when i builded IDX for a friend, the same 517 audio transistor was hot after 5 minutes.
I had 4 lithium batteries 3.7v in series, which gives more than 20v when full charged.
Later when i removed one of those, everything was ok, bc517 remain cold.

[gaby_sult]

Hello CDI,

ok i will, i use this schematic
[ATTACH]38933[/ATTACH]

everything ok, discrimination work great, just BC517 getting hot
for U3 i use TL074 , and U4 LM393

thank for reply

[kt315]

check modulation signal from U7 Q3.

[Wahyu]

Hello CDI,

ok i will, i use this schematic


everything ok, discrimination work great, just BC517 getting hot
for U3 i use TL074 , and U4 LM393

thank for reply

[CDI]

Hi eduardo and Lamoiz

I have problem Q4 BC517, always getting Hot, with or without sound beep.

BC517 has different pinout than mpsa13, check that transistor, also try to replace U4.

[Wahyu]

Thank for reply lamoiz,

i use 8ohm speaker, and i use lithum bateray 12v, what volt at R39 22K?