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Ayuda para encontrar este cable plano

ileanoska — Tue, 04 Oct 2016 21:13:23 GMT

El cable es de un control élite de xbox one no sé el nombre ni sus especificaciones y quisiera saber si aún tengo oportunidad de encontrarlo antes de que tome la deci de comprar otro control mando las imágenes sería de mucha ayuda su información , como pueden ver un extremo no tiene la entrada la desgarre completamente

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Need help with video wires!!! Please help!!!

Former Member — Thu, 25 Feb 2016 22:23:26 GMT

Hello my name is Brenton. I recently have started a project to make my ps2 portable. I got a car backup screen for the screen for the portable. I have been trying to solder the screen to the board. Only one problem, I don't know what I'm doing. I have the video cable cut and I have soldered it many times to the correct spot i have found off a diagram. I just recently figured out I need ground. I have no idea which wire the video ground is. I doesn't even seem to exist. There are 2 video inputs, a white and a yellow. The only other wires are red and black, which are positive and negative for power. So my question is, which wire is ground? How do i find it? And will just soldering the yellow wire and the ground give video input? Thanks ahead of time. I appreciate your answer.

RE: Need help with video wires!!! Please help!!!

mconners — Fri, 26 Feb 2016 00:45:21 GMT

Also, what type of video cable did you cut? Do you have any pics?

Mike

RE: Need help with video wires!!! Please help!!!

shabaz — Fri, 26 Feb 2016 00:42:33 GMT

Did it work with normal cables before you hacked the wires? If you didn't test this, then you won't be sure it worked in the first place.

If it did work with normal RCA cables connected between the screen and PS2 then it should work if you use wires soldered to the same locations as the connectors. RCA connectors have two conductors - the outer conductor and an inner one.

There is no yellow wire, just a coax cable with yellow jacket. Inside there is an outer braid and a centre conductor. The outer braid is the 'video ground' that you're referring to and the centre conductor is the video signal.

Detailed photos will help.

RE: Need help with video wires!!! Please help!!!

mconners — Fri, 26 Feb 2016 00:40:31 GMT

Can you give us a bit more information? What kind of car backup screen, what diagram are you following, etc...

Mike

RE: Insulated versus not insulated copper wire

jw0752 — Thu, 12 Mar 2015 01:11:04 GMT

Thanks for the links.

John

RE: Insulated versus not insulated copper wire

D_Hersey — Wed, 11 Mar 2015 21:55:47 GMT

http://www.arrl.org/files/file/Technology/tis/info/pdf/8405015.pdf

http://www.fair-rite.com/newfair/index.htm

http://www.cwsbytemark.com/

RE: Insulated versus not insulated copper wire

D_Hersey — Wed, 11 Mar 2015 21:38:08 GMT

When we characterize a magnetic material, we use a complex number. I just was woken up and can't recall the labels for certain, but the first is like the magnetiness. How much it increases the inductance on a coil when inserted instead of air. 'Permeability,' I think. The second term relates to pokiness. If the material is poky, it goes into a fridge magnet rather than a coil. I think the second term is called 'permittivity' or 'loss tangent.'

Magnetic materials conduct. So we have to worry about 'eddy currents.' Line frequency Xformers use laminations of silicon steel to block eddy currents. A ferrite core is made out of some kind of ferritic ceramic, IIRC. Above this, 'powdered iron' is used, which is powdered metal in an epoxy binder.

As they go up in frequency, they have to sacrifice Al for speed, as more of the core is comprised of non-conducting, non-magnetic binder. Same with ferrite, faster mixes imply lower Al.

Al is a measure of permeability in terms of square root of inductance per wire turn, or something.

RE: Insulated versus not insulated copper wire

D_Hersey — Wed, 11 Mar 2015 21:19:47 GMT

Now, if you kept to twenty turns, but used two cores instead of one, that would only get you to 2*N quatloos of inductance.

RE: Insulated versus not insulated copper wire

jw0752 — Wed, 11 Mar 2015 21:13:30 GMT

Apologies to Margie for hijacking your thread.

Thanks Don as always for the great input. I will have to give your suggestions a try. My design was very inefficient. I should have renamed it the Joule Pit but it worked.

John

Insulated versus not insulated copper wire

Former Member — Wed, 11 Mar 2015 00:05:05 GMT

I noticed someone used .0808 copper wire that is not insulated for a project, but I only have insulated, and the parts list does not make a distinction of which one to use...if I use the insulated wire, will that make a difference in the outcome of the project? Thank you!

RE: Insulated versus not insulated copper wire

D_Hersey — Wed, 11 Mar 2015 21:10:40 GMT

Note that when you add windings to a core, you are increasing your B over an area, rather than a line. So if your twenty turns yields N quatloos of inductance, putting forty turns upon the same core yields 4*N quatloos of inductance. Since you paid for a finite number of magnetic domains when you bought your core, saturation in the latter situation would come proportionately sooner.

RE: Insulated versus not insulated copper wire

D_Hersey — Wed, 11 Mar 2015 21:04:58 GMT

Oh, John, I am fighting a bitter and fitful struggle against ignorance myself. Pardon my tone, I am distracted by extraneous events.

Efficiency of your power supply, which you were brave to construct and to blog about, is easy to measure. As you gain SPICE-fu, your switcher designs will become slicker-and-slicker. Efficiency is the amount of desired output divided by total effort. If you measure the potential and current you put into your circuit and take their product, that's your input. The power going to the LEDs is the output. Now, I think, from what I have read, that you can 'bifilar wind' the transformer if your potentials aren't greater than something like 42 V in the US. Above another potential, you are obliged to wind it as you did, plus put insulating tape on the transformer core. Inbetween, secondaries are typically wound first then tape, then the other wind. 3M is one manufacturer of appropriate tape. I am told that if you have greater intimacy between your primary and secondary, you can exploit capacitive coupling as well as magnetic coupling. Bifilar and trifilar winds are preferred due to their analytical simplicity in most situations. Another thing, when you wind it your way, you can use square magnet wire if you want, it confers a slight advantage. In high-frequency situations, litzendraht wire is the conductor of choice.

You use a power drill (battery powered, on slow mode, wear leather gloves)`to twist the magnet wire together before winding the resultant twisted-pair upon the core. If you are as crazy as I am you have magnet wire with different-colored enamel.

If doing it this way yields a measurable increase in efficiency, it may be worth the trouble. Might be an interesting experiment to conduct, upon your return to the bat-cave.

RE: Insulated versus not insulated copper wire

jw0752 — Wed, 11 Mar 2015 16:16:33 GMT

Hi Don,

It is a ferrite 0.5 inch core. The wire came out of a small transformer that I salvaged from an old computer switching supply. There are (2) 20 turn windings. If the windings are not arrayed properly the reason is ignorance. As far as winding it was very difficult with these old eyes. I was nearly permanently cross-eyed when I finally completed it. It is part of a Joule Thief circuit operating at 1.5 volts. I believe the frequency was about 45kHz.

John

RE: Insulated versus not insulated copper wire

D_Hersey — Wed, 11 Mar 2015 09:33:17 GMT

I presume the turns-ratio is 1:1. You can thread the last turn behind the penultimate turn to hold things together.

RE: Insulated versus not insulated copper wire

D_Hersey — Wed, 11 Mar 2015 09:26:08 GMT

What is the material in that transformer? Is it 52 mix? Is that a transductor or a transformer? What size core? How many turns? What inductance? What SRF? Why did you array the coils separately as you have, rather than wrap the core with a twisted pair? What potentials are you operating at? If that is used in some kinda saturation-based gadget oscillator, what frequency does it operate at?

How you doin'?

RE: Insulated versus not insulated copper wire

jw0752 — Wed, 11 Mar 2015 02:03:49 GMT

Is it possible that what you see as uninsulated wire is really wire that has an enamel insulating coating? This type of wire is used on transformers and inductors and looks like bare wire but in fact is quite well insulated. Here is a coil that I wound using enameled wire that may look uninsulated but really is insulated.

John

RE: Insulated versus not insulated copper wire

gadget.iom — Wed, 11 Mar 2015 00:32:31 GMT

Great stuff. Thanks.

RE: Insulated versus not insulated copper wire

Former Member — Wed, 11 Mar 2015 00:32:03 GMT

Thank you so much. If I remember, I will let you know how it worked out!

RE: Insulated versus not insulated copper wire

gadget.iom — Wed, 11 Mar 2015 00:09:07 GMT

Without more details it would be impossible to give you a definitive answer, but generally I would say yes - Insulated is fine/better.

RE: An alternate processor for tms320f2812

Former Member — Fri, 07 Feb 2014 12:04:27 GMT

Thank you. I think that will work.

An alternate processor for tms320f2812

Former Member — Thu, 06 Feb 2014 16:37:56 GMT

Hello

I'm doing a PWM based project which requires the generation of 100 kHz reference wave and 400 kHz carrier wave.

I was told to use a DSP TMS320F2812 for this.

Due to the high price of the processor mentioned above, I'm looking for an alternative to fulfill my project requirement at a lesser price.

Can someone pls help me out?

Thanks in advance

RE: An alternate processor for tms320f2812

Former Member — Thu, 06 Feb 2014 18:47:14 GMT

There are specialized DDS frequency generators that will do this, or any other waveform that can be programmed.

Direct Digital Synthesis (DDS) & Modulators | RF / IF ICs | Analog Devices

That may be cheaper than using a DSP. For example, the AD9831 is less than $7. You can probably get samples.

RE: An alternate processor for tms320f2812

Former Member — Thu, 06 Feb 2014 17:23:23 GMT

I need both a sine and a square wave. I will be generating and using them for PWM them individually. But for the frequency range mentioned above, I need to find another processor other than a DSP. As for precision, I need a 10 V signal (variable at run time).

RE: An alternate processor for tms320f2812

Former Member — Thu, 06 Feb 2014 16:46:10 GMT

Do you need a sine wave? Or do you just need a square wave? How much precision do you need? You can precise square waves out of an arduino (ie atmega328p). Sine waves would require some other strategy. PWM implies you need square waves, I think.

Using a DSP just for this is expensive overkill. You must have other requirements.