trash

[trash]

I have been looking for the nice wide stuff, but I can only find tape that is 15mm wide. I get it from bunnings. I think they call it binding tape ?

When you get the new wing (or any new plane), run one strip along the underside of the wing. If your
prone to flying into things, then you might like to consider doing the leading edge, but you have to be VERY carefull. The leading edge is one of the most important parts of the plane, if you have any lumps or bumps on it, you can seriously effect flight. Same goes for anywhere on the top of the wing… placing tape or anything on the top surface of the wing is just a big no.

No probs on the new wing, I’ll let you know when I place the next order for some stuff. I can get other spare parts for these planes too. How much did you pay for your A40 and where’d you get it from ?

I have some mirage planes coming too. These are smaller than the A40. I’m keen to fly one.

The firebird that dick smith sells is a good plane for a novice pilot who’s never flown before.
They fly well, though I don’t like them, they look too klunky for me. They are pretty stable
and seem to survive crashes well. I notice that all my friends FB’s have propeller cut marks on the under side of their wings.

I received a pic of a new flying machine today that looks cool. It’s a styro UFO. No big deal there, seen that before, but this one only has a single propeller. The fuselage has vents in it to duct the air through, but the struts are actually blades too. The torque that normally requires a tail rotor for is used to spin the chassis and produce lift. It’s $40 aus plus shipping.
Got to have me one of these 🙂

I’ll try and find a picture of it on the net somewhere and link it in.

A construction site ? Oh you really need a bigger park !

[trash]

I don’t see any reason why they couldn’t share an antenna on the RX. You might need to do something if the local oscilators interfere.

[trash]

Sorry for being out of the loop for a few days.

You’re right bithed. The absolute first upgrade should be bearings !!

As for xtals, any set of 27Mhz xtals will work.
(provided they are the right cut and IF.)
I can’t remember the IF freq, but I’d guess it was 455KHz. You can order custom made xtals from Hy-Q or cheaper from “bright star crystals”
in victoria.

On my mini-Z, I got an RTR out of the box in Hong Kong. I took it to the local indoor race track and was rather amazed that my new car sucked !
With help from the locals, I got the upgrades…

first New Bearings… very important.
next was Carbon H plate kit.
Aluminium Ball Diff
Rear piston suspension
Rear roll suspension
Motor Heat sink
Turbo 01 motor + ESC

Aluminium Front Rack
Front Suspension Springs

New mags – makes it look pretty

To top it off I use the genuine Kyosho Tyres
20 and 30 deg, though I leave the orignals on for concrete.

The batteries are Sanyo AAA 800mAh’s.
Top shelf stuff. After hearing 5 different people recomend them, I had to have them. I didn’t regret it.

There is still a few things which could be improved. But I’d say if you have the money, go the fully worked car else you’ll have fun spending a lot of small amounts over time. 🙂

[trash]

Hmmm… lets see … for half the time the current is flowing forward, then the other half it is flowing back the same amount. I smell a rat, my meter shouldn’t move at all !!

[trash]

That plane is the same plane. I’m supprised you managed to break the wing. They are though as nails. You might care to invest in fibre tape.
It makes any plane almost indestructable.
Though some of my friends can push that limit.

How does $10 aus sound for a new wing with motors ? Plus postage. I combine all my stuff into one shipment to save costs as shipping is the biggest cost. Something tiny like a wing would be only something like $2 in a big shipment.

I’d buy the wreckage, but I think you may want to fix it now 🙂 Feel like you might be able to afford a ducted B2 now ?

I’ll let you know when I order stuff again.
It takes about 7 days to get here.

I love my little A-40, it broke the same switch wire on mine on sunday. Soldered it on site.
I was flying it in the RAAF drop zone when 3 hercs flying in formation flew over the zone.
Looked very cool to see flying at 100ft with the hercs behind it at 1500ft. Wish I had the camera with me.

[trash]

My home is where batteries come to die !

[trash]

Do you have a pic of the A-40 style plane you have.
They are easy to repair and I can get any spare parts for them you need dirt cheap.
I’m really not sure which planes crash the best, I’ve seen them all come unstuck at one point in time or another. The A-40 is the one that has done best out of my planes. Though all my planes last longer than friends because I fly safer, and I reinforce them before I fly them. I’ve deliberately flown my A-40 into a tree to prove it could survive. (it flew out the bottom after bouncing off several branches).

[trash]

Gold isn’t the most conductive metal, it’s actually Silver. Gold is used because it’s more inert than silver, and cheaper than platinum.

The skin effect is correct, but it actually has very little to do with antennas, it’s more to do with transmission lines.
Though it can be said, that the thicker the antenna’s elements, the more broader its bandwidth.

It doesn’t matter what you make your antennas out of. It can be ANYTHING ! I’ve made antennas out of fences, power lines, even trees and people !
(though it is common knowledge a human being makes the best TV antenna). I even have an antenna that is plastic ! (it requires some explaining).

So it doesn’t matter what sort of metal you use in this case. There is something that I have overlooked. It’s a thing called ‘velocity factor’
it has to do with the speed at which electrons travel in wires. In free space C=3×10^8, in a metal wire it is slower.

I’m not sure that such a short antenna has a flat radiation pattern, so keeping it a 90 deg to the floor may not make any difference. Short antennas are rather unpredictable so the only way to find out is test them.
The guitar string antenna looks pretty cool.

The coil antenna, you just take a long length of copper enamel wire and make a loop big enough that will fit inside the chassis. 10 turns is usually enough and then you leave a tail for the antenna. I haven’t experimented much with it, so it’s new ground. 🙂

[trash]

Can you make the power meter run backwards for me ? 🙂

[trash]

Go the cat5 !
Hmmm… I take it you don’t mean the nylon strings ? 🙂

Coathanga – Maori word for car antenna.

[trash]

Ah, sounds like you live down Cronulla way.
Parramatta and Penrith parks are a bit calmer,
and more thermals availble.

You might be supprised, I think your B2 might be able to manage some chantels and wingovers with a bit of practise. Even loops if you set it up.
Though coastal air is not very helpful.

I’ll let you know how much the GWS cost when the price for them comes in. You might be supprised.

How often do you crash and what is the cause ?

[trash]

Yep, they all sound like inductors.
The ferrite is used to change the inductance of the coil. The core of the coil effects the inductance. Air cores create smaller inductors than ones of the same size with iron.

You can change the inductance of a coil by…

changing the core
changing the number of turns
changing the diameter of the coil
changing the wire

Changing the core is easiest, changing the number of turns you can cheat by putting tap points along the coil and using only part of the whole coil.

Capacitors are just two metal plates with a gap in between. The gap or insulator is called the “dielectric”.

You can change the capacitor size by…

Changing the size of the plates
Changing the distance between the plates
Changing the type of dielectric

[trash]

Generally for your BCG car, it doesn’t really matter how long your antenna is.

Antenna Theory Time. 🙂

There is a very important number everybody should know. 3 x 10^8 ! (300 Million). It’s also known as “the speed of light” (in metres per second).

It is the “C” in E=mc^2, but I don’t think we need to go that far 🙂

We use this number to work out the ‘wavelength’ of a particular radio frequency.

The formula is L= C/F
C= 3 x 10^8
F= Frequency in Hertz (27MHz = 27000000 Hz)
L= Wavelength (in metres)

Example:
[3×10^8]/[27×10^6]=11.11 metres.

Antennas work best a specific lengths.
Usually these are 1/4, 1/2, 3/4 and 5/8ths of a wavelength.

Stick with 1/4, it is simple and the smallest.
11.11 / 4 = 2.78 Metres.

So the best length of antenna to use is 2.78 metres long. Not very practical ?

Loading coils help make antennas look electrically longer or shorter than they really are. But for antennas so drastically short of their ideal length, it doesn’t help much.

You may of course care to try experimenting with other types of antennas like a loop antenna.

[trash]

Excellent Talldude !!
I actually have one on order from Hong Kong,
my friend ordered it, it isn’t mine. I’m saving a couple of dollars and might order a GWS ducted fan B2 in the next shipment. They look very cool,except for their clunky landing gear 🙂

http://www.gws.com.tw/english/product/airfly/b-2.htm

Have you tried any aerobatics or thermal soaring with your B2 ? Where do you live, and where do you fly it ?

[trash]

BJT’s no problems …
got a few other things to describe.. it’s in the list.
I’m not too good with fet’s, I understand their insides, I’m not too good with them in circuits.
uA sounds like the person to describe them.
I was hoping some other people might have some good descriptions of how some components work.

[trash]

I don’t like them standard… they are dull and boring. with the upgrades…. they are much more fun. I still got to find a ‘simple’ program that converts avi to mpg so that I can make them availble for download somewhere. avi are too big.

[trash]

hmmm.
http://www.hobbytron.net/Sky-Surfer-RTF.html

[trash]

Hahah, classic. Can you come around, my xmas tree needs a professional touch !
yes, the mention of the coil is the smoking gun. 🙂

[trash]

Thanks ph2t,
That’s a small switchmode boost converter.
Though I’m not sure that is what’s used.
I don’t own a real tomy, is there a small coil on there somewhere ?
You can step the voltage up to something like 3 volts and throw away 0.5V with the diode to get 2.5V. (I’m ignoring internal resistance of the diode).
I’m not a real diode whizz, I just look up the specs like everybody else and use them when needed. I can’t even remember voltage drops for Germanium diodes. But both them and Schottky diodes (0.3V) are generally used as high frequency detector or mixer diodes, usually in AM radio receivers.
The diode may be a detector diode (uA .. where’s that RX board cct diagram ?) or it may be used because it fast switching for a tiny high frequency switchmode power supply.

Interesting stuff.

[trash]

Doh !
Millicandella … 1/1000th of a candle power brightness. Don t confuse candle power with real power.
A 10mW red led is not the same brightness as a 10mW green led. Your eyes are more responsive to green than red. The candle power is colour biased already, so a 1000mcd red LED is the same brightness as a 1000mcd green. Jaycar’s latest 20000mcd red LED is a bodge. It is only about 8000mcd.

Good stuff ph2t, be buggered if I could even guess LED voltages.
The voltage is a characteristic of the doping, like Gallium Arsnide or Indium Phosphide. So it is possible that three kinds of RED leds all have different voltages.

[trash]

See what happens kids when you mix your drinks !
🙂

[trash]

Wow. looks like I’m going to get this months NS,
I only get it when they have a catchy cover story.

I wonder how long normal biro’s work or why they work in space. Writting upside down here on earth they don’t last long.

[trash]

light + led = power is correct.
A tiny voltage appears across the two leads.
They work like tiny little solar panels though there isn’t enough energy to actually power anything. They do work well as light sensors.

The complementry is …
It is amusing is that solar panels don’t produce light when you apply power to them.

[trash]

S urface
M ounted
D evice

F eild
E ffect
T ransistor

Fet’s are a bit different from common ‘bipolar’ transistors. I have no idea why they are called bipolar ?

I don’t know what’s inside a grandcell charger,
I’d guess it’s some sort of pulse charger.

I just blow cigarette ash away ? 😯

The common biro pen requires gravity to work.
The Americans spent thousands of dollars developing a pen that would work in space.
The Russians used a pencil !

I might add that the space shuttle never had graphite fragments get into it’s circuit boards.

[trash]

I blow stuff up all the time, sometimes deliberately sometimes not.
I meant to mention a few good things for working with SMD components. The first is a matchstick.
Lick the end (not the head end stupid !) and touch the SMD component. It picks it up and you can place it on the board to be soldered holding it down and in place with the matchstick.
Next is a fine point tweezers for picking of components. And of course a nice fine tip soldering iron.

uA likes to be a bit more specific than I do.
Ask him what the T stands for in FET ?
I’m willing to be it’s not going to be “thermonic” or “tube”.
blackeye:

[Author]

Posts