sprejemnik REX 4

[Karl]

Kok dolga mora bit antena???
Mi je stran odletela!!!!!!!!111

Povejte!!!!!!!!!!!!111

[tornado]

http://www.shark-racing.com/Ingles/Tecn ... enaing.htm
Lp Rado

[Karl]

Kaj nej k navadno tenko žico prlotam al kako?

Men stran neki ne dela mi lahko napišeš kok mora bit dolga?????

[GHOST]

Kaj nej k navadno tenko žico prlotam al kako?

Men stran neki ne dela mi lahko napišeš kok mora bit dolga?????

The antenna length of your receiver is important for best range and for better
quality of the reception.
There is a mathematical formula to determine this length:

t=c/l

where:

t=antenna length

c= light speed (for this purpose considered to be 300.000km/s, equivalent to
300.000.000 m/s.

l=transmitter frequency

The most usual frequency in R/C boating is 75 MHz. Within this frequency there are 30 available channels, with frequencies between 75.410 MHz and 75.990 MHz. As you can easily see in the formula, the higher the frequency the shorter the antenna length. Let's check the right lengths for our
receivers, considering the available frequencies.

1. for the shorter frequency of the range (75.410 MHz)

t=300.000.000/75.410=3.97 meters=156 inches

2. for the higher frequency (75.990 MHz)

t=300.000.000/75.990=3,94 m=155 inches

From this formula, two observations arise:

a. the difference in length from the higher to the shorter frequency is negligible - 1 inch in 156";

b. it's impossible use in a boat the antenna length calculated by the formula.

And so, should we forget the ideal length idea?

Not necessarily. Scientists discovered that submultiples from the ideal length can be used with almost no loss. So, 1/2, 1/4 or 1/8 of the calculated length
are almost as efficient as the original. So:

156/8=19 1/2"

155/8=19 3/8"

19 inches and fraction, close to the length we find in our receivers.

And how about the 27 MHz frequency?

Using the same formula, you get 54 inches for1/8 wave or 27 for 1/16.

That's it guys. Science has a solution for (almost) everything.

[Barbara]

Js mam tut ta sprejemnik pa je tut antena u k*** pa tega nč ne razumem pa če bi mi lahko kdo to razložu.



Lp Barbara

[Kremšnitar]

waw


t=c/l


t=dolžina antene
c=svetlobna hitrost (300k km/s)
l=frekvenca oddajnika

zračunaš, dobiš inče. pretvoriš v centimetre. pol pa deliš z 2, 4 al pa 8, kakor ti paše. rezultat je dolžina antene.

[mrgigi]

ehehe
klepec, poklici tistga ki ti je prodal...
al pa poglej na netu...jeti...rex4...specific.....antena lenght
ne se res delat zabite, na netu je vse in se vec, sam minuto cajta rabis pa mal u glav. najlazi je nc ne kapiram
lohka pa nacins meter in pol od oka pa bo tudi delal

[Barbara]

Še en uprašanje:

Js mam krmilnik JES 350

Use lepo namontiram pol pa baterijo prklopm pa kr čez krmilnik dela, zakaj????????????????????????'

[bogomila hosta dostojevsk]

pi... si trapast da maš REX

a to je pes al kiva

[BORIS HAZDOVAC]

Zakaj mi letalo brez kril ne leti???

[Fuelboy]

Fantje umirte se malo!!!

...teme s 'sočnimi' izrazi so bile in bodo brisane

Smatrajte to kot opozorilo, ker bomo v nasprotnem primeru na forumu prisiljeni uvesti določene sankcije.

[Matjaz]

Za dolžino antene se pozanimi. Žica pa mora bit NUJNO samo bakrena,
ker če je kositrana se lahko zlom znotraj uvoja pol pa k boš šel
letet boš vrgu model 5m bo še delal pol lohka pa greš kr novga delat.
Ti povem iz lastnih iskušen.

[joža]

kremšnitar:
rezultat dobiš v metrih(c- v m/s frekvenco oddajnika v Hz) potem pa če ti paše pretvoriš v cole ali pa v kaj drugega (osnova je vedno metrični sistem)

[joža]

tisto z deljenjem dolžine maš pa prav

[borisk]

poglej tole stran
http://www.yourzagi.com/beware.htm#ant-length

btw rezultat dobiš v inčah(25.4 mm = 1in.)
pol pa pomnožiš tisti rezultat z 25.4 in dobiš dolžino v milimertih.

upam da sem komu pomagal

lp,boris