squalle 0 Report post Posted January 16, 2006 da blok is to block DC from going into ur trafo and hence ur trafo will run cooler to start, dun put such things first that one put in later after everything works out and becareful when playing with live of the mains k? Share this post Link to post Share on other sites
Kube 0 Report post Posted January 16, 2006 Speaking of live mains...do you connect a 3-pin plug directly to the circuit board or PS itself, or do you solder one of those 3-pin sockets in first...if so, where can I find those sockets? Share this post Link to post Share on other sites
siriuz 0 Report post Posted January 16, 2006 oops i forgot about da blok but nvm la hahaha i got the parts liao. total about $15 for the psu. i intend to use IEC socket for connecting, then can use the same power cables as computer. the sockets can get at sls most shops. koba should have also. i couldnt seem to find 11k resistor in sls so i got 2 x 22k to parallel instead. heater is powered by the ps, but its part of the tube. two of the pins on the tube, its not a separate unit. Share this post Link to post Share on other sites
squalle 0 Report post Posted January 16, 2006 mm yea, i use those IEC socket can get either in SLT (not SLS la) or koba live, use wire soldered on it, then solder on the trafo primary (one of it) then neutral, go to switch, then fuse then trafo 11k that hard to get? not necessarily to be 11k u can change those values, as long as you can get 12.6v for the heater part and yea, 2 wires connected to 2 pins of the 9pins of the tube out of 9pins of the tube, 1 is not used 2 for heater 3 pins for each channel (anode, input grid, cathode) siriuz: how much did u pay for the trafo? and wat rating? either the current output or the wattage Share this post Link to post Share on other sites
siriuz 0 Report post Posted January 16, 2006 oops! i think i getting senile slt become sls. then i forgot buy bridge rectifier. win liao! trafo is 6VA 15-0-15 , $4.30. i saw one 3VA one, say 0.3A. but then i see like so small, so i buy 6VA one Share this post Link to post Share on other sites
squalle 0 Report post Posted January 16, 2006 you need 6VA anyway but 0.3A means 9VA. smaller size but if it's using thicker wires, then might be possible not so sure tho' I've never made or studied how to design a trafo bridge? u can make a bridge using 4 diodes btw or u wanna get from me? or u can always get from koba depends which place is nearer for u Share this post Link to post Share on other sites
siriuz 0 Report post Posted January 16, 2006 yea i know can make with 4 diodes. i'll be going down to sls prolly this friday after SP career fair, so its ok =P i'm in no hurry, since the tubes aren't here yet. i was thinking 3VA like very weird leh, i do some mental calcs turn out like only around 0.1A. so i dunno why it write 0.3A. so i bought the 6VA one lor Share this post Link to post Share on other sites
Kippei 0 Report post Posted January 16, 2006 Thats what happen to me... and i gotta go back to change.... From bell isnt it the trafo Share this post Link to post Share on other sites
Kube 0 Report post Posted January 16, 2006 Lol, siriuz...what time are you going to leave the place? I attend SP, but finish only at around 5, think I might be able to join you? Also contemplating an idea...should I come up with a PCB board for the SOHA? I mean, it seems quite popular, and since I have technical aid and the right programs at the poly, plus the ability to use the PCB manufacturing lab... Or are you sticking with the design that came out on headwise (the one with the star ground) and/or using perfboards?... Share this post Link to post Share on other sites
siriuz 0 Report post Posted January 16, 2006 yea bell electronics Share this post Link to post Share on other sites
Kippei 0 Report post Posted January 16, 2006 (edited) You get more flexibity with perf cause not all components fit the original pcb size. Meaning you gotta find the exact same components to fit the pcb. As you can see from my soha the FC caps are 2 -3 bigger than squalle and other ppl. Also i used round recitifers instead of the square ones Edited January 16, 2006 by Kippei Share this post Link to post Share on other sites
siriuz 0 Report post Posted January 16, 2006 @kube: i was thinking to leave at 4pm after the talk by electrical and electronic engineering, but i think i'll sit through media and info comm, then meet you? i think this friday we head down to koba instead, you want to get all the parts and the amp parts also right? i didnt see any tube sockets at slt today actually i bought ferric chloride and blank double sided pcbs today. wanted to surprise you guys Share this post Link to post Share on other sites
Kippei 0 Report post Posted January 16, 2006 planning to use photo resist or toner Share this post Link to post Share on other sites
Kube 0 Report post Posted January 16, 2006 No problem, though does Koba open until quite late? (travel to chinatown is about 1/2 hour or so). Also asking...are you goint to add the LED portion? Just in case later I decide to add that part...what value of R should I use? Share this post Link to post Share on other sites