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.

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

What 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

Lol, congrats i suppose!

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.

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

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.

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  

lol, nice one, keep up the good work