Rectifiers drop voltage? I thought with a DC current it would effectively be a short circuit.

If all you are doing is dropping 1v, just shove a single resistor in series. 1v is an incredibly small amount to drop at low current like 0.5A

what... 1/0.5 = 2Ohms... you need a 2 Ohm resistor... its hardly worth even bothering with a voltage divider.

Zener Diodes... again... how would you go about causing a volt drop like that? Last time I used them was in a feedback circuit to set off a "clipping" LED on a power amp, as current flows as it approached breakdown voltage (i.e. filtering out low voltages/signals in order to only allow high through) I dont see how youd do it with either a rectifier or a zener diode, and certainly not a plain ol diode. Be interesting if you could post it up like as I could always be mistaken.

What im worried about is not blowing up the adapter, but instead you burning out your usb ports

Ahhh just did some googling.

Youre doing a shunt voltage regulator, if its a zener diode I see! Nice... but somewhat over complex for what you need surely.

Quote from: M3ta7h3adAhhh just did some googling.

Youre doing a shunt voltage regulator, if its a zener diode I see! Nice... but somewhat over complex for what you need surely.

yeah ...it was but forgot loads of stuff, was one of the only things i could remeber with reg voltage

gonna try feeding about 20ma to start see what it does .. mainly cos it the only resistor combo i can do atm

currently stripping a broke multi meter for resistors atm .. got most of what i need
might be able to test this tonight

QuoteWhat im worried about is not blowing up the adapter, but instead you burning out your usb ports

already shorted it a few times when i was testing the voltage of the feed .. just turned the adapter of and back on started connecting again stright away .. so hopefully i wont pop out

woohoo .. done 1st test .. and it didnt pop it

got 3.8v from dropping v with resistors, should have fed about 16ma or less

gained about 1 -2dbi in net stumbler ....

gonna go to maplin tomorrow to get more resistors so i can crank it up

Lol, congrats i suppose!

cheers done 2nd test dropped 10 ohm got 4v now but dbi is even worst than it was unmodded .. might have hit the point where the usb cant feed any more power ... ether that or i re-wired it wrong .. .gonna find a power pack and try that

Windows will pop up a message if you a drawing too much power. Youll probably find a sweet spot where you apply a particular voltage and it gives you the best results. Drop it a little and see what it does.

QuoteWindows will pop up a message if you a drawing too much power

..

oh didnt know that .. it hasnt done that yet so cant be that .. thinking about it i didnt add any ohms to the r2 when i dropped 10ohm of r1 .. might be the cause.. gonna add some to r2 now

Take a trip to Maplins and buy a variable resistor IMO.

QuoteTake a trip to Maplins and buy a variable resistor IMO.

already been to maplins once today to lazy to walk back

added 100 ohm to r2 and its dropped even more



think ive re-wired it wrong .. it must be sucking power out of the amp instead of putting it in

or there is some other factor i havent figured out yet?

Go back to maplins and buy a variable resistor or two. Get a 1kohm and a 10kohm. Should only cost pennies. Connect the middle pin to where you want to apply the voltage. If it still drops off, use a larger resistor.

just double checked ive re-wired it backwards .. was tapping power of the amp
so the 1-2dbi increase the 1st time might have been from the 2nd ariel when i removed the rf shielding cos that doesnt apear to be attached anywhere..

so now is a real test if im gonna pop it ..

woohoo holy **** it atually worked

1st scan is unmodded
2nd scan is without rf shielding which 2nd antenna was behind i think
3rd scan finally re-wired properly at 4.14v but probably less once its drawing power
cant check volts while in operation cos ill short it out, stuff in the way. it barley got warm so recon im gonna try pumping more into it  

bumped the voltage up more .. dont even know what its at now .. seams that the more i pump in its only helping distance now and its atually impeading close range stuff this network is the furthest way .. oh i also picked up 2 networks ive never seen before, so it must be doing something

1st scan in unmodded version 2nd modded


this network is bit closer than the last


this is the closest network to me .. signal has atually dropped .. ? dont understand it myself


something must be limiting the poweroutput now just dunno what it is, might have sensors to stop it pulling more power of the usb so it doesnt damage it and its compensating for the mod ? must have about 4.5v into it now and recomeneded max was 4v .. havent burnt anything out cos it operates fine?

lol, nice one, keep up the good work