that thing almost all the shop ada, u just ask for third hand tool or whatsnot..but sumtimes the apek dunno, so what i did was i print out the pic and show it to them..i know, kinda lame of me, haha!

the birth of DIY junkies, yeaaaaa! Welcome to the clubzz

I can get you guys good OPAMPS if you want, gimme sum lead time, i can supply OPA2227 and OPA2132, and also i haf lots of CHEAP spare of JRC opamps, all are dual opamps, so much easier to make CMOY using them.

u can still power it down to 9V, not many opamps require high voltage application. I made once a simple CMOY powered by a car's electrical system, hooked to an iPOD AUX-ed to the stereo, when the engine's running and the alternator kick in, theres a ringing noise due to the electrical system power ripples superceeding the power in the stereo itself.

By using the inverter>dc psu again u would be able to remove this noise, but they are FAR easier methods of doing werk. A tighter regulated psu can supply clean 12V from the car's electrical. 12v runs fine to power ur stock 18V amp, no problem.

or you could build buck-boost capacitor dc-dc voltage double..phew...long name! Or get MAXIM voltage doubler.

Eokboy, the amp u built for march, whats the layout about? ar there any regulation or whatsnot in there? Why must it use EXACTLY 18V?

The maxim dc thingie, sure..its phreaking small, SOIC size, no DIP, hehe!

Then eokboy amp can be run off 12V no problem. The matter of inefficiency doesnt rely much on voltage, but more towards current which the buffered ab amp u haf would sufficiently supply.

i dig my 8085 and 8051 man, scored straight A+ with appreciation from lecturer that and digital.

(but i did kinda did badly on DSP and Control System...)

mini cube is a 3 channel cmoy with built in regulator+battery charger..cool!

Anyone wanna build almost anything..i think i haf parts enough to make them, so just drop me a PM.

ahh..looking for me?

Neways, PCB diy punya will never be up to par with pro board with glass epoxy+silks creening and track pre-coating bla bla..

at USD10 was it for the mini cubed..its a good price (u can get cheaper if u make in bulk from the local store)..however, shipping for the mini cubed is a PHREAKING PIA!!

I can make DIY mini cubed, but single sided, anything else is wire jumpered, and maybe the option of DIP sockets..hmmm...but it wont be nice looking.

double sided diy is based on ur material, but via connection between surfaces are almost impossible to DIY since u need perfect precision to align bottom n surface plane and not to mention via connection...aiyo..

wanna try to make pcb too, afaik the only thing closest to pcb i haf ever made was design and testing, production is skipped, only theoretical..gotta go and get stuffs tomorrow!

Sifu PCB-maker, tq tq!

no, i was never in the process of making PCB board physically..i design and test..thats all, haha! So now want to start..

haha, wat a u ppl, u guys can dream la

Heres a 10 min werk in Cadence on a simple 78XX voltage regulator with the tab bolted to the plane as heatsinks. Comments?

COuld haf been smaller and more organized..but rusty Cadence..

This post has been edited by ijan: Sep 11 2007, 08:40 PM

no la, the others should host the thred id efer one was opened since i dun haf much knowledge on pcb building..still looking for my cadence manual...

wanna make my first PCB project, my 16A 24V-DC super regulated PSU...

This post has been edited by ijan: Sep 11 2007, 09:17 PM

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This post has been edited by ijan: Sep 11 2007, 10:12 PM

See what happens tomorrow then...

that is like prototype, i dun think its good..i was rushing it so i can print it out at office and try to make one tonight (my home laser printer is rosak..demmit).

Nets are thin, they could haf been bigger, layout is not optimized, they could haf been shorter..much more can be done, item footsize could haf been more accurate, prototype nyiaa 20mils track, see matte paper+toner transfer+laminating machine can do the werk or not..

Cadence Orcad Layout..i haf yet to learn the crook and nook and its far from perfect..i thin sum other sifu here pakai protel made much much better board design..

My home laser cannot print black..but nanti hantam try print yellow toner..hehe!

ur bench psu, the board u buat urself too ka? what is the IC at the center of the board? linear regulated bench psu ka?

neways, on the idea of the high power high precision benchmark psu with adjustable current+voltage, might i suggest OPA549T for all your need?

http://focus.ti.com/lit/ds/symlink/opa549.pdf

See page 12 and 13,

PROGRAMMABLE POWER SUPPLY

A programmable source/sink power supply can easily be
built using the OPA549. Both the output voltage and output
current are user-controlled. See Figure 10 for a circuit using
potentiometers to adjust the output voltage and current while
Figure 11 uses DACs. An LED connected to the E/S pin
through a logic gate indicates if the OPA549 is in thermal
shutdown.

This post has been edited by ijan: Sep 15 2007, 10:20 PM