heady

Q00, thanks for comments. I did plan but not for months. When you are inexperienced, however much one plans, sure to miss out something. But it's still fun!

Would you believe it? Drilling into plastic is just as bad as drilling the tin cans. I am casing my Pimeta and manage to tear the plastic casing with the drill. Major OUCH!! I am hoping the nut used to tighten the sockets etc will hide the tears somewhat. I also manage to forget the positioning of a cap and one of the sockets is obstructed by it. Looks like I have to reposition the cap since I've already drilled the hole for the socket. Stupid things I do but I hope those of you reading will avoid my mistakes. Will post the picture when I move the cap. I feel really at the moment. --- Update - here are the pics of my battered Pimeta clone, which isn't minimalist any more!!

I don't play with either gameboy but my son prefers the SP because the backlighting allows him to play in the dark. Of course. that may be a disadvantage if he sneaks it into bed with him.

Bpribadi, when you order, please order one for me as well, I will pay you back. I also like the one with the AC socket at back. Thanks

tropic - aiyah, so sad. Cannot find this size caps here. The only one I could find is the Rifa/Evox 1uF polycarbonate (grey) caps in SLT but it is not square but rectangular and the leads are spaced 4 holes apart. Will be problem to populate this board if the smaller sized caps not available. But the other caps you used are interesting. What are they? Thanks.

Hey, I want in for one case. Thanks.

tropicalrips, looking good. Where you get the 1uF Wima in Singapore?

Hi, I think I solved the mystery of the bursting cap, it's my lousy soldering. I probably overheated the small cap. Cest la'vie. I have now taken out all the Nichicon caps and replace with four 470uF Elna Silmic caps and two Evox 1.5uF polyester caps, all connected to V+ and V-. The sound was a little harsh and dark. So I added another two 0.15uF Wima polyester caps and two 100uF Elna Silmic caps. The amp is now sounding better and the higher pitches are cleaner. Will let it run in and report progress. Hmm I think I prefer the sound of Nichicon caps although I don't know why there is a difference. Looking forward to the challenge of casing this amp.

bpribadi, what type of cap is the yellow plastic box cap? Polyester? Thanks.

digi01, your work is as beautiful as sijosae! I also envy your access to the casings you have used.

Firefox, I agree thin is relative, I have no objective standard to compare except it looked thin although it has much more strands than those really cheap wire sold in SLT for hookup. jtfoo, I wll certainly try using cat5 wire which I have lots of. bpribadi, ok, now I know how you use the s-vhs cable. Do you think it is good enough for headphone extension as well? I hope all the gurus will continue to share. This thread is interesting.

Hmm, looks like Cat5 and power cables are quite popular choice for wires. But jtfoo, Cat5 too stiff to connect to input, vol pot and output sockets right? Or do you use it also for these points. Thanks.

Happy to report that the oscillation and hum is gone once I removed the capacitors which connect V+ and V- to the virtual ground. Somehow that doesn't work for my set-up. I also discovered one of my caps which is connecting V+ to V- is bulging on top. Looks like I have to change it too. I will have to go to Koba and get some replacements. The cap is rated 50V and my supply is only at most 18V, so must be manufacturing fault right? Or is it possible for my circuit to produce higher volt than supply, impossible right? Thanks.

Hi all, I used a very thin stranded copper wire for connecting the parts on my amps. I don't like it as it is too fine but the insulation is more heat resistant than most as it doesn't shrink back during soldering as much as others. What do you like to use most? Please share what and where you got it. I am sure many of us will be interested. Thanks

bpribadi, let me check if I have a suitable cap first, if not I will sms you. I bought some caps earlier after misreading the labels, so I may have one. The battery is actually a tiny bit bigger than Eveready 9V.

Thanks bpribadi, will try it later tonight. Battery is GP brand rechargeable 8.4V NiMh battery. I bought from SLSq for $28 for two together with charger. The charger has no auto switch off so must remember to switch off manually. Still cheap to buy with charger, as the battery is sold for $14.90 each without charger.

Thanks digi01, appreciate your comments very much. I have a black plastic box for it, not very sexy. Unfortunately now the amp oscillates after I added more caps. Trouble-shooting time!! There are two problems. One is a very high pitch and nearly inaudible screeching which is probably oscillation and the other is hum when I touch the input wires. BTW I braided the wires. aaa. thanks for your info. Although I frust about it, still it is better to know so I won't go back to RS again.

Alamak, when I asked Federal, they said they never heard of it. I searched Farnell on their site and it reported not found. So I had to buy from RS Components and drive to Tuas and getting lost to collect and pay more for it. Of course this is about two months ago. Thanks for the info, aaa, save me agro if I need to re-order, I have 5 more. I ordered more since it was so difficult to get. Argh.

Hi Bram, transistors used to bias op-amps. LEDs to bias transistors. Giddy already. Never mind, if some expert builts it and share how, then can try.

Anyone care to explain what purpose the LEDs serve in the SDS schematic? In layperson english if possible. And huangyong, do you have the list of parts that goes with this? I have heard good things about the SDS amp. Thanks.

I am good for #2

Bram, the pic is before adding more caps. The plastic box came with a MagLite and belong to a friend who from whose fingers I pried it away from. I have unfolded the amp as the box has sufficient space and it is plastic so won't conduct heat away from buffers. Hopefully will update the pic later. I burned another TLE2426 when I connected the V+ and V- in reverse. Poof, there goes $5.00. Bad to do diy late at night.

Hi drumma, you must search for the type of perf board used in the Tangent which is hard to find in Singapore. I found using the type with straight copper strips easiest to use but you need to have a way to cut the strips where you don't want it to connect. If you are doing this first time, better to stick to the gain used for the example, ie gain of 11. Later when you are better, you can try changing the gain. Just my 0.02 worth.

Update. I have dropped the idea of fitting this into a Hudson tin because I found the Pimeta can sound A LOT BETTER with the caps which was originally specified. So I added more capacitors to it and it won't fit into a Hudson tin anymore. This picture is after I folded the two halves of the board and secure it with ties. I will show the update Pimeta in the larger box I found for it when it is done. Hopefully this weekend. Thanks.

Well, if Jason wants to make some money legit by selling the opamps when he paid for bulk purchase, I think it is ok. Just because some people can get some chips free doesn't mean everyone can get any amount of chips free. I bought two AD8620 from tangent and paid S$60 for them but then most others got theirs free. What to do??