fwh1599 0 Report post Posted May 6, 2004 (edited) My Twinkle(OP+DB): Case Test No.1 It used MUSE BP 10uF/25V as coupling and feedback Case Test No.2 It used WIMA 1uF/50V as coupling and feedback(R8=10K,R7=68K) Case Test No.3(PCB Ver.Test 2) It used WIMA MKS-3 1uF/63V as feedback,and DC coupling(R8=10K,R7=68K) Edited May 6, 2004 by fwh1599 Share this post Link to post Share on other sites
jtfoo 0 Report post Posted May 7, 2004 Very nice.. What are those yellow ting that you put around the transistors? BTW, nice PCB and layout.. Share this post Link to post Share on other sites
fwh1599 0 Report post Posted May 7, 2004 Very nice.. What are those yellow ting that you put around the transistors? BTW, nice PCB and layout.. It's rubber cannulation(heat shrinkd),around Q1-Q2,for holding same temperature. Share this post Link to post Share on other sites
jasonhanjk 0 Report post Posted May 7, 2004 It helps to prevent either one of the trans to go into thermal problem by sharing both trans temperature. Nice PCB work you got there.... Share this post Link to post Share on other sites
jtfoo 0 Report post Posted May 7, 2004 (edited) Jason, When can you start your PCB lesson? Though I may not venture into it, won't hurt to know something more. So the yellow thingy is the same thing when I asked you why you tie rubberband around the transistors. So temp of both transistor are uniform.. Edited May 8, 2004 by jtfoo Share this post Link to post Share on other sites
fwh1599 0 Report post Posted May 7, 2004 (edited) I will accomplish Case Test No.4(PCB Ver.Test 3) in next week. It include 4 betterment: 1.DC coupling(It is most important improve for sound of Twinkle); 2.Strengthen supply after regulator; 3.Increase protect circuit without realy(Sensitive and not hurt timbre); 4.Increase user-friend iindicatory circuit(Light at natural,flash at problem) I wish it is finally PCB for Twinkle,It have high quality sound and security. Edited May 7, 2004 by fwh1599 Share this post Link to post Share on other sites