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Old Oct 07, 2012, 01:22 PM
Blade mSR freak
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Irish Hills - SE Michigan
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It's not hard to put separate series resistors ahead of your connector, just solder them inline with one wire to each LED and heat shrink over them.
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Old Oct 07, 2012, 06:17 PM
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Quote:
Originally Posted by Galand View Post
@Gooniac, I imagine that within a your strips all the leds are identical. Are they wired in parallel?
If it does not work, having learned something, it's then back to soldering individual resitors. Anyway it's an interesting issue for a handful of stupid leds.
The strips are not all identical in length but they are in manufacturer. I got them all at Hobbypartz but they range in size from 6 all the way up to 60 LED's. And they are all the same brightness. I guess the one thing that I could do would be to check the voltage at the end of each strip to see what they are doing. But the brightness is the same from each to the other. they are all wired in parallel and I have never had any issues with some being brighter than others.

Quote:
Originally Posted by hydro_pyro View Post
A few hundredths of voltage drop difference will cause major differences in brightness between LED's, and it's typical for them to vary by a tenth or two. Try it on the bech first if you don't believe me. some of them will barely light up, even amongst identical colors.
The LED's are all the same brightness even with the main battery starting to lose power. They all dim at the same time and come back to the same brightness as well. Again I need to hook up a voltmeter to each to see if there is a difference in voltage but from just looking there is no difference in brightness.
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Old Oct 07, 2012, 08:11 PM
Blade mSR freak
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Irish Hills - SE Michigan
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...But the LED's are NOT wired in parallel. Look at the strip. LED, LED, LED, resistor... repeat. There's three LED's in SERIES with a series resistor, and each of these series groups are then connected in parallel with each other. Nowhere is there an LED directly in parallel with another LED. Each cut-mark on the strip is a division between these series groups.

Even if the forward voltages have slight variances, they still light fully because one LED cannot affect the voltage drop across the others. The voltage drop across the series ballast resistor in each group is equal to the supply voltage minus the sum of the forward voltages of the three LED's.

I learned this stuff 25 years ago, when I was just a kid. I can't believe I'm arguing with adults about this.

Evidently I'm wasting my time explaining this, since I'm being taken for a complete idiot.

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Old Oct 08, 2012, 01:40 AM
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Quote:
Originally Posted by hydro_pyro View Post
...But the LED's are NOT wired in parallel. Look at the strip. LED, LED, LED, resistor... repeat. There's three LED's in SERIES with a series resistor, and each of these series groups are then connected in parallel with each other. Nowhere is there an LED directly in parallel with another LED. Each cut-mark on the strip is a division between these series groups.

Even if the forward voltages have slight variances, they still light fully because one LED cannot affect the voltage drop across the others. The voltage drop across the series ballast resistor in each group is equal to the supply voltage minus the sum of the forward voltages of the three LED's.

I learned this stuff 25 years ago, when I was just a kid. I can't believe I'm arguing with adults about this.

Evidently I'm wasting my time explaining this, since I'm being taken for a complete idiot.

I now understand what it is that you are saying....so you are not crazy...it was just a misunderstanding. I am wiring the strips in parallel but the LED's themselves are in series. I understand now...
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Old Oct 08, 2012, 04:13 AM
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I have been considering this plane or the sr trainer by dynam...Anyone here own or fly both? I am still just flying a couple of 4 channel fast gliders for several months...and think moving up to one of these rather then crashing and fixing my warbirds i bought.. I like them both and both have flap kits included so i really want the best handling plane out of the two...thx
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Old Oct 08, 2012, 12:47 PM
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Quote:
Originally Posted by hate2crash View Post
I have been considering this plane or the sr trainer by dynam...Anyone here own or fly both? I am still just flying a couple of 4 channel fast gliders for several months...and think moving up to one of these rather then crashing and fixing my warbirds i bought.. I like them both and both have flap kits included so i really want the best handling plane out of the two...thx
Both planes fly the same. If anything the SR is a little bit more docile than the Cessna. But the Cessna is for sure a stronger airframe. The wings on the SR are a little brittle. But they both fly great!
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Old Oct 08, 2012, 03:58 PM
Blade mSR freak
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Irish Hills - SE Michigan
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Quote:
Originally Posted by gooniac33 View Post
I now understand what it is that you are saying....so you are not crazy...it was just a misunderstanding. I am wiring the strips in parallel but the LED's themselves are in series. I understand now...
I'm still not sure you quite understood what I was saying...

My little diagram represents the strip itself. The strip repeats that same pattern over and over. It's three resistor-ballasted series LED's, in parallel with three resistor-ballasted series LED's, in parallel with three resistor-ballasted series LED's in parallel with... over and over. That's why when you look at the strip you can see LED, LED, LED, chip resistor... LED, LED, LED, chip resistor...

Putting strips in parallel with other strips is just fine, of course.

The reason they only put three LED's in series on the strips is because they probably have around a 3 volt drop across each LED. Three in series has a 9-volt drop, and the resistor eats the rest of it. If they used more than three LED's in series, the strip wouldn't have enough voltage to run on 12 volts.

My comments about series resistors was pertaining to Galand's comment about using the wing and tail LED's wired with each other in parallel, which will not work well. He needs to have a separate resistor for each LED... or put a couple of them in series with a series resistor like they do internally with the strips.
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Old Oct 08, 2012, 11:56 PM
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Originally Posted by gooniac33 View Post
Both planes fly the same. If anything the SR is a little bit more docile than the Cessna. But the Cessna is for sure a stronger airframe. The wings on the SR are a little brittle. But they both fly great!
Thx Gooniac.... I am also considering fms sky trainer...not sure if it is better than dynam or not...Price is slightly more but its a bigger plane with flaps and i think nav lights so price is right...
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Old Oct 09, 2012, 06:33 AM
Blade mSR freak
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Irish Hills - SE Michigan
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The Dynam does has flaps, you just need to add a couple of micro servos to operate them. If you run both servos from the flaps channel, you'll need to reverse one of them internally, or connect a "servo reverser" dongle into one of them between the Rx and the servo.
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Old Oct 09, 2012, 09:54 AM
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Originally Posted by hydro_pyro View Post
The Dynam does has flaps, you just need to add a couple of micro servos to operate them. If you run both servos from the flaps channel, you'll need to reverse one of them internally, or connect a "servo reverser" dongle into one of them between the Rx and the servo.
Yes i know the dynam 182 has flap kit...I just learned something new...I guess there are video's that show how to reverse servo's in this manner... PS are there super slow servos made for flaps which are best???and if so which ones are they? all i have is a switch not a knob for flaps..thanks..
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Old Oct 09, 2012, 10:21 AM
dbc
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United States, FL, Brooksville
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I've have nearly every foam Cessna 172/182 available including both the 40" and 55" FMS planes.

The Dynam remains one of my favorites due to its generally robust construction, very light weight, excellent flight characteristics, and modest price.

The 55" FMS weighs about a pound more than the Dynam and can benefit from the use of flaps. The Dynam is so light that flaps are really unnecessary - they might be fun but not generally needed. I've logged over 330 flights on mine without flaps and feel no need to install them.

I also fly my 40" FMS without flaps. But my ST 48", FMS 55", Art Tech 52", Starmax 63", and T/S 73" all have them.

With the exception of the heavy Starmax, the other flap equipped planes can be flown and landed satisfactorily without actually using the flaps.
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Old Oct 09, 2012, 10:54 AM
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The Dynam is much better than the rest. Much lighter and more powerful as a result. And it is also stronger. The struts are metal in the Dynam and the wing is better.
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Old Oct 09, 2012, 12:38 PM
Blade mSR freak
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Irish Hills - SE Michigan
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I flew my Cessna off water with home-made floats for the past two summers, they weighed about 6 ounces. Flaps really helped reduce stall speed, and lowered landing and take-off speeds too.

Even on wheels, the flaps are effective at slowing the plane down for landing approach.
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Old Oct 10, 2012, 02:36 AM
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Seymour,TN
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182

i got my plane last week while putting it together 5 of the screw heads stripped while putting them in the two for the landing gear got stripped one all the way in and the other just shy of being all the way in and the others stripped in the wing only one got stuck in it but one of the did not strip which leads me to i got a bad batch i contacted nitroplanes about the issue but just in case any ideas on how to get them out?
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Old Oct 10, 2012, 05:42 AM
Blade mSR freak
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Irish Hills - SE Michigan
Joined Jan 2010
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Lay a soldering iron against the screw head until it wiggles, then it should back out easily, even if the head is rounded out a bit.

The plastic inserts are drilled, but not tapped for the screw threads. Sometimes they fail to cut their threads when you first screw them in. If the screw is slotted with a Dremel for a flat screwdriver, you might be able to try it again with the screw heated up a bit.
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