Hello, I'm new to this forum, I tried searching on Google and here but no answers: 1) [Etching]: I've got HCl 19%, H2O2 6% (strongest which can be easily bought in Croatia) and H2O )). I plan to make an 3.5cm x 2cm PCB, with toner transfer method. I'm a n00b in this, but I think that there wouldn't be necessary as much as 1L due to this small board sizr... In which qty. should I add these chemicals for etching in the concetrations above? And what if: a) H2O2 is 3% b) H2O2 is 30% (as I heard with this one etching is done in ~15 sec.) 2) [Adapter]: Board above will be used for PSX to Parallel adapter. Found on Emulatronia. Will that adapter work with PS2 joystick (original page says only PSX)? 3) [Adapter]: a)Which (zener) diodes should I use to lower the voltage from USB (5V) to 3.3V? Or... b) Can I use two 1N4007 joint in series? Please, put your answers under numbers, I hate when I must "decode" the answer from the block of text. Also don't suggest me to "Buy an PSX to PC/USB/etc.converter/adapter/etc. etc." because I know about that and now I want to try this DIY soulution.
tough luck.. you gets your answer in the format people can be bothered with In order of relevance.. IF the original plans state only ps1 controllers than that is what works... you will need a different design for ps2 5v from usb? .. need to drop to 3v3? .. then you need a 3v3 zener. 2x1N0447 in series.. what for? A BZX series should do unless there is any specific forward drop characteristic of the 1N4007 which is specific to the application (don't see it myself.. the 1N4007 is a standard junction diode) Etching from mask? .. read the instructions supplied with your chemicals.
OK, I did understand you, thanks. But can someone else answer me 1st question then? Oh, I meant can I use 2 x 1N4007 to drop voltage to 3.3V? Edit: Question 2 solved. WORKS. Edit: Question 1 change: Can I use Fe(III)Cl, but in some smaller qty? for example if 250g goes on 1L can I put 125g on 0.5L or 72,5g on 0-25l (which I think should be enough for this size...)
as long as the chemicals are mixed in the same concentrations the amounts don't matter.. xxx per xxx .. in the same proportion .. it's the concentration of the solution that is important whether it's 10ml or 50,000 gallons. the 1N4007 is rated to have a 1.1v forward drop at 1A .. but less current will appreciably alter that. You will have to measure the current taken by the circuit with a controller connected from a 3v3 source then do the numbers.. it's easier to just use a 3v3 zener as on 4 different sheets I saw anywhere from 0.4v to 1.7v quoted for the forward drop depending on maker.. and obviously it's not a relevant figure for most diodes in the small signal category. They should do the job, but if it all goes bang don't blame us. Modify anothers circuit without knowing what the consequences might be isn't really sensible.. a zener is connected across (parallel) to the power source.. a series pair of 1n4007's will have to be in the supply rail. They will not provide any overvoltage protection, and you could achieve the same with one resistor if you work out the total current drain of the circuit. Why do people come here asking about electronic circuit design modifications when it's so clear I'm the only actual qualified electronics engineer here? I haven't seen the circuit so I can't even begin to guess how much current it might draw.. .. would do far better on some proper electronics forums because this is well outside the remit of this site.
