Čime se zanimam... (ovih dana )

[sir Oliver]

Ma Srbin imao muku samo dok nije izmislio Japanca. Pos!e mu bilo lako.

[acivoJ]

...'oće struja kill.

 

[guja011]

oće i ti mali akulumatori, kad padnu na glavu.

[acivoJ]

Ta priča, njih se najviše i plašim.

[Okibokis]

Ja malo, malo pa citam negde na netu,da baterijska napajanja takodje prave neke probleme sa zvukom,tj da se nisu bas nesto pokazala?Da li je to istina?

[guja011]

"naravno".

tkz zmijsko ulje a u stvari kiselo grožđe.

[Okibokis]

"naravno".

tkz zmijsko ulje a u stvari kiselo grožđe.

Citao sam sta je napisao nas clan DVV...

Citat: Dobar elektronski stabilizovan izvor napajanja je zaista marginalno losiji od baterije, ali zato nema niti jednu, jedinu manu baterije, jer vuce sta treba, koliko treba samo kada treba. Naravno, cena te pogodnosti je veca suma eura koju valja odvojiti i vise prostora koji je potreban unutar kutije, ili vec gde. 

Dodatna pogodnost stabilizovanog izvora napajanja je sto prekticno eliminise potrebu za bilo kakvim zastitinim kolima protiv prevelikih struja cak i u pojacavacima snage - sta ce im, kada sama stabilizacija odredjuje raspolozivu struju? 

[Zen Mod]

los primer stiva za pocetnike

 

zadnja recenica  daleko od istine

[Vix]

Pa koliko ja kontam, stabilizovana struja je samo to-stabilizovana. Moze biti mala a moze biti i poprilicno velika. U drugom slucaju, ako nema zastite, eto belaja

[stein]

Ja malo, malo pa citam negde na netu,da baterijska napajanja takodje prave neke probleme sa zvukom,tj da se nisu bas nesto pokazala?Da li je to istina?

 

Mrzi me da prevodim, a usput postoji rizik da u prevodu nešto pogrešno napišem:

 

 

Batteries vs Linear Power Supply

Batteries are low noise, right? That's why people want to use them in audio systems. The most common assumption is that because they are a pure DC source they must have no AC noise. Unfortunately we live in a world where nothing is pure, so let's look at why batteries are not so great a source of power as some may want you to believe.

 How a battery produces power

Batteries produce power through a chemical reaction. Every type of battery will have a slightly different chemical mixture that is used to generate power.

Batteries have a voltage rating and a current/time rating called Amp-Hours. Amp hours basically say how many hours the battery will last if it's drawing one amp of current. Because many systems draw variable loads, a 10Ah battery will not necessarily last 10 hours. It may last 20 or it may last 2 hours depending on the system it is connected to.

As a battery drains, the amount of chemical compound available to produce electricity drains. That means there's an exponential decay on the amount of power a battery can produce. So a battery at 100% will have far more capability of producing fast transients than a battery at low charge. 

Battery Noise Generation

Batteries have a substantial amount of high frequency ripple. This means there is a large AC component to their DC output voltage.

What causes this ripple?

The battery's chemical reaction will generate different types and frequencies of noise. The chemical reaction changes as the battery drains. That means the spectrum of noise changes as well. The change in load also impacts the way the battery is draining, which will alter the chemical reaction and thus the noise produced. 

As a battery drains so does the output current and the output voltage. As these elements change the voltage will become less stable and the transient response slower.

So ultimately you are creating a non-constant source that has varying spectrums of noise, that is constantly changing, and produces the exact noise we want to get rid of.

Regulating and filtering battery power

The first thought is to regulate and filter the battery power. This can help the battery's performance considerably, but it does not compensate for the variations that occur as the battery drains. Batteries in particular do not have a pump, so as current demands stay the same and their ability to produce that current diminishes the regulators and filters become progressively less effective. 

Here's the catch. Regulators are very sensitive to input impedance. They like a stable input or they must regulate both Line and Load variations. A battery's output impedance changes with drain.

 Different batteries sound different

Every battery will have a different chemical composition and thus different chemical reaction. This translates to different levels of noise and different resulting sounds. 

The noise generated is usually very high frequency noise up into the mhz or ghz ranges. This is not only more difficult to filter, but it's the exact noise that pollutes digital audio the most. The noise generated may be less than the noise filtered out compared to a SMPS, but it is still generating noise that is a challenge to compensate for.

Recharging the Battery

For one, recharging is a hassle. Many companies have circumvented this by having micrcontroller charging circuits to automate the process.

Many chargers only begin trickle charging when a battery is below a certain charge level. Introducing AC noise into the battery's path means the system has to filter out both AC noise and battery noise. You also loose the benefit of being off the grid. If the AC noise is somehow isolated from the battery's DC output using dual batteries with a switching circuit or other method then the charging will still alter the chemical reaction of the battery.

When a battery charges it creates the opposite chemical reaction to return the battery to it's initial chemical components. In this event you have opposite chemical reactions occurring at the same time.

GROUNDING

This could be one of the single biggest issues with battery power. By using a battery you are no longer connected to ground in the same way. That means that shields become a noise "cage" rather than pulling noise away from the system.

In addition, you end up having ground loops along cables and your system must find an alternative path for ground noise.

 

Ostatak članka: http://www.coreaudiotechnology.com/batteries-vs-linear-power-supply/

[Okibokis]

Prica na netu se vrtela oko Technics Se -R1 koji se prodavao jos 90-ih,pa je bilo za i protiv oko isplativosti pravljenja i tih manjkavosti baterije,koje sam ja ocigledno pogresno razumeo.

 

http://www.technics.com/us/products/r1/se-r1.html

[guja011]

Mrzi me da prevodim, a usput postoji rizik da u prevodu nešto pogrešno napišem:

Ostatak članka: http://www.coreaudiotechnology.com/batteries-vs-linear-power-supply/

ima i u ostatku članka

http://www.coreaudiotechnology.com/products/

to pojašnjava smisao napisanog tj citiranog.

[stein]

ima i u ostatku članka

http://www.gpbatteries.com...

[guja011]

teo i ja to da napišem, al nemam pojma kako je pravilno, da se evt pripadnici manjine ne uvrede.

[Zen Mod]

jes

 

Gujomir je poznat na vorumu kao uvek politicki korektan

 

[zbotic]

Multidisciplinarni pristup

 

http://www.channld.com/batteryaudio.html

 

Btw tko misli da baterije "nemaju šum" je battery divac

[progster]

Multidisciplinarni pristup

 

http://www.channld.com/batteryaudio.html

 

Btw tko misli da baterije "nemaju šum" je battery divac

Mene tako rekli, šta ću.

[micro]

Multidisciplinarni pristup

 

http://www.channld.com/batteryaudio.html

 

Btw tko misli da baterije "nemaju šum" je battery divac

 

A i ovaj ga usere malo, imao prije 10-tak godina alkalne punjive i po njegovom izdrze 3-4 punjenja praznjenja ako ih praznis kao klasicne punjive(vise od 25% kapaciteta) , neki uredjaji ne trpe klasicne punjive zbog manjeg napona pa sam uzeo te alkalne punjive , koristio ih mozda malo manje ciklusa od NICd ili NiMH . Punio ih sa punjacem koji sam dobio sa njima , koji jos i dan danas radi i punim sa njime panasonikove akumulatorske baterije.

[stein]

jes

 

Gujomir je poznat na vorumu kao uvek politicki korektan

 

 

Ne znam za njega, no sam skont'o da se i ti trudiš biti politički korektan... kad si uz'o auto u političarsko-crnoj boji... Hoću reći, nisam još vid'o političara u autu neke druge boje...

[Zen Mod]

a jes

 

i ja ih uvek vidim na choperima crne boje ......

 

[Mikorist]

Nemoj da mi je neko dirao Gujomira 

[guja011]

evo čime se zanimam..

odfikarena polica u pozadini je nužno zlo da bi ova skalamerija mogla da se smesti što dublje

da ne smeta na iovako plitkom stolu. na slidži 2 je buduće mesto.

Vin 220-230-240v , Vout 0-300V/10A

moćno, ha?