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31  Using Arduino / LEDs and Multiplexing / Re: Looking for advice on driving 3w and 1w LED's on: October 22, 2012, 10:17:58 pm
I ended up ordering some NCP3065PG and CAT4101, I will give status update on them once they arrive.
32  Using Arduino / General Electronics / Re: What inductor is this specifically? on: October 21, 2012, 07:41:02 pm
That is correct I am trying to do the same product as above, at least if it is worth it to do so anyway!  It's open hardware to begin with, they just don't state what part that inductor is.
33  Using Arduino / General Electronics / Re: What inductor is this specifically? on: October 21, 2012, 07:00:13 pm
Yeah it truly is unique to every setup.  I noticed I made a mistake in my post above, I said 50MHz to 2.2MHz, that should be 2.2GHz smiley.  I think an SDR would be good enough to analyse the noise floors and RF output of all of the components for both of my frequencies in use, from there I guess I will have to look for problems then work on fixing them!  I am thinking good filtering caps on power and toroids should be sufficient to keep EMI away?

I will also use my DSO Nano to look at any potential issues in power rails too, though I doubt it is going to show me anything high frequency though. 
34  Using Arduino / General Electronics / Re: What inductor is this specifically? on: October 21, 2012, 04:59:07 pm
I am trying to be preventative of issues.  Ultimately the efficiency of range is what I am looking for, I want a clean noise floor both EMI and RF for the 100mw 433MHz data link to be able to both transmit and receive to the greatest distance possible, and for my 1.3GHz video link to get the best range possible without anything interfering with anything else.  There will be a motor and servos running on the same battery too, as well as autopilot, OSD, GPS, Etc, so I think filtering will make all of the difference to get the best performance.

That particular product in my OP according to it's specs are supposed to filter something from 1000MHz to 1400MHz noise, I guess the idea is to prevent noise from getting into the video TX, but I don't know enough about RF to know really if this circuit was good for the purpose or not. 

I am still waiting on some components to get in, plus I think I am going to order one of those USB SDR's (Capable of 50MHz to roughly 2.2MHz), which I could use as an RF meter to test RF noise, and I will see if my DSO Nano is capable of spotting any power noise on the power rails.

At this moment I am trying to really pre-plan everything as much as I can.

One thing I know is that 433MHz has the ability to create harmonics close to 1.3GHz, and 1.3GHz can effect GPS, but luckily the airframe I am installing this onto is quite large so separation for RF components should be pretty good, but it also means longer wires and EMI to consider, toroids will be used on pretty much everything getting a power rail smiley.
35  Using Arduino / General Electronics / Re: What inductor is this specifically? on: October 21, 2012, 12:41:18 pm
So you do not believe the above PCB design would actually filter 1.2GHz noise?  It's supposed to filter power to the 1.3GHz TX itself according to it's specifications, not on the 433MHz link.
36  Using Arduino / General Electronics / Re: What inductor is this specifically? on: October 21, 2012, 05:30:04 am
It looks to me like a 1000uH (1mH) shielded power inductor.  Digikey has about 14 PAGES of these, in various sizes and current/power ratings (the latter is likely to be important.)  You can probably come close by picking one that looks the same and has the same size (measure it) (or just pick the highest power rating in that size.)  For a better match, try to measure the DC resistance of your existing coil and match that as well.

The eBay part looks like something entirely different.

I don't have one to measure, I am just basically building that circuit myself.  My gut feeling was to look for something that looked the same, now though I know what to look for specifically! 

Shielding certainly is important too, this is going to be used on an FPV plane and my goal is to make all electronics as efficient as possible, and there are so many things going on in such a tight space, you have analog video on 1.3GHz being TX'd at 700mw, I am going to have a 433MHz transceiver operating bidirectional at 100mw, quite a bit of servos, motor, lights, so I want to make sure electrically everything is as perfect as possible smiley.
37  Using Arduino / General Electronics / Re: What inductor is this specifically? on: October 21, 2012, 04:12:05 am
It appears from looking at the PCB (Front and back), that the power rail goes straight through the inductor (2 points).  The purpose of this circuit is to filter 1.2GHz noise on power rail.  Instead of spending $15 on a pre-made one I would rather just get the proper inductors and do it myself smiley.  If anyone can point me in the direction of figuring out what inductor would work for specific frequencies (And filter caps too), that would be awesome.  I want to make one for 433mhz as well.
38  Using Arduino / LEDs and Multiplexing / Re: Looking for advice on driving 3w and 1w LED's on: October 21, 2012, 02:36:36 am
I also found the cat4101 1a
39  Using Arduino / General Electronics / Re: What inductor is this specifically? on: October 21, 2012, 12:15:16 am
Would it be safe to say that http://www.ebay.com/itm/5pcs-Common-Mode-line-filter-10mmx6mmx5mm-Inductor-1mH-1A-/150924583713?pt=LH_DefaultDomain_0&hash=item2323ce6321 would be a drop-in replacement then?
40  Using Arduino / LEDs and Multiplexing / Re: Looking for advice on driving 3w and 1w LED's on: October 21, 2012, 12:10:27 am
What about STCS2ASPR?  http://www.mouser.com/ProductDetail/STMicroelectronics/STCS2ASPR/?qs=sGAEpiMZZMsE420DPIasPoxeLwn8SKwbvNs8EYaD8YU%3d

Rated to 2 amps constant current sourcing...  and can handle the voltage to run some in series plus has PWM pin smiley.
41  Using Arduino / General Electronics / What inductor is this specifically? on: October 20, 2012, 10:26:50 pm
I am trying to figure out what inductor is on this PCB, can someone help me identify it?  Thanks!

42  Using Arduino / LEDs and Multiplexing / Re: Looking for advice on driving 3w and 1w LED's on: October 20, 2012, 06:51:19 pm
My main battery will be a 4 Sell lipo, so battery voltage will be between 14.8 to 16.8 (as the battery drains), though I am open to putting in a separate 3 sell (11.1 to 12.6v). 

The layout I am planning is 3 of the 3w's upfront to be a headlight, so they can be pwm'd as a group and would be ideal for a series, 2 of them will be mounted on either side of the fuse to light up the wings as well as provide flood and landing light, they could be series too, then there will be 1 1w on each wing tip (red/green).

I have been thinking about all of these factors and I know that any sort of linear DC-DC is going to dissipate a LOT of wasted heat and considering the plane  is made of foam excess heat is not preferred smiley.
43  Using Arduino / LEDs and Multiplexing / Looking for advice on driving 3w and 1w LED's on: October 20, 2012, 05:56:36 pm
I am going to install some high power LED's on an FPV Airplane for nightflying purposes.  I want to drive 5 3w LED's, and 2 1w LED's with a minimal of power usage as possible, so I think PWM would be the best bet also so I can control brightness.   The 3w LED's (White), have something like a 3.2v forward voltage and 750ma current draw at full brightness, the other 1w LED's have similar forward voltage but 350ma current.

I am considering the ULN2803 but I am concerned with heat dissipation as well as PWM ability, so what does everyone recommend?  Ultimately I will probably only run these lights 1/4th of their power if not less most of the time except for take-off's and landings.
44  Development / Other Software Development / Re: AnalogDebounce: New Library for debouncing Analog Keypads on: October 17, 2012, 05:29:08 pm
Indeed you are correct, the current defaults are based on a 10bit ADC, though really once you set it up you could do button.adc_key_val[0-4] = whatever.

I am going to figure out a much better way to handle the number of buttons and different resistor values. 
45  Development / Other Software Development / Re: AnalogDebounce: New Library for debouncing Analog Keypads on: October 16, 2012, 04:31:01 pm
The minPressTime and repeatDelay are properties of the class. 

As far as specifying the resistors that is interesting...  I will have to experiment around with the idea and see if it would work well.  I do want to make it easier to specify buttons and values beyond the standard set now.

I do appreciate the feedback!
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