Dead_Nid

The Oberheim OB-XA, a synth from the 80's, uses the connectors on the photos to connect voice cards to the main board. I want to replace them all and am trying to source them but I don't even know their name. thanks in advance for any help! ps. sorry for the crappy mobile pics, but I think anyone who is familiar with such connectors will figure it out.

greetings Audioguru! Hi Ante! Glad u remember me! Our console's PSUs were finally relieved from their pain with some great BHC filter caps and a neat job refurbishing almost everything. A big fan (a home-use one) cools them down especially on these hot summer days that they need it so much. Thanx a LOT for these links, they are really very helpful! I will come back when my knowledge is stronger and am preparing to build a regulator or a balanced power transformer or both! Meanwhile if anyone has a suggestion, sharing it would be wonderful. Especially for DIY 230V single-phase regulation. thanx again! take care

you're kidding me! Is it such a complicated device this power conditioner thing? No one of you electricity experts ever built or planned to build one from scratch? Apart from being very interested in building one for my needs, I am also so curious to find out why conditioners (AVR whatever they are called) are so expensive even in the low Watt range. Also all these AVR advertised UPSs do anything at all to regulate the mains voltage or is it just a "theoritical" AVR? Sorry if i'm putting up primitive questions and sorry that I don't have the time to investigate this thing all the way by myself. I need some guidance, somewhere to start, please. Comments, links, cheers, swears...something Thank you all and best regards!!! Nick

Hello folks! Anyone ever got involved in a DIY Power Conditioner? Capable to handle at least 1000VA. Please share thoughts and/or schematics. Does anyone know if this cheap APC Line-R 1200VA Power Conditioner is any worth at all? I find it strange to be so low in price (about 50euros here) when professional power conditioner cost a hell lot more. Thanx a lot!

thanx indulis. please explain "inrush current". have you read the rest of the thread? It is a linear regulated psu. thanx again!

Happy new year to everyone! Haven't tried any special diodes yet. I want to ask two very newbie things that I am curious about: 1) My PSU uses two 4700uF smoothing caps (in parallel so total capacitance is 4700x2). I am going to replace them because they are very old. But as the opportunity arises I could replace with greater capacitance. Is that better in smoothing quality (apart from space and cost issues)? Remember, this an audio mixing desk's power supply. So...I am thinking of placing 6800uF or 10000uF and that will mean a total of 13600uF or 20000uF...Even theoritically, is there any benefit as the capacitance gets higher and higher? Is there any chance that it can cause trouble instead? 2) What about voltage ratings? I was told (by Dan Lavry) to use caps with voltage ratings as low as possible. But in some manufacturers charts I have seen that the higher the voltage rating the lower the impedance. Any clue? I am between BHC, Nichicon and perhaps Black Gate caps. Any suggestions? Thank you! Best regards and happy,creative 2006!

Thanx Ante. I haven't done any mods yet...too much damned work...but I am going to start very soon.

hmmm bloki, do you know if the LT1083 or LM338 will oscillate when caps have low ESR? Ante, have you ever used all these diode types in linear regulation circuits so as to make a fair comparison? Best regards, Nid

Hi Ante, you are right. Even though I have currently no known problems I think I am trying to accomplish the most efficient, clean energy (RF free) power supply I can make for my mixing desk. Nevertheless I've read that Hexfreds give a significant performance gain in the overall sound such as better resolution and reproduction of high frequencies and dynamics. Maybe that is another hype, that's why I am trying to get other people's opinions. Thanx a lot! Best regards, Nid.

...by the way, is "Schottky" and "Shotkey" the same thing? What about FRED and Hexfred? Is there any difference in performance between using discrete diodes and bridges?

Hi dear friends! I've recently discovered the existence of Shotkey and Hexfred diodes which are said to be the best type used for rectification in audio PSUs. Can someone enlighten me on this as well as diodes in general? (fast,soft recovery etc) Thanx a lot! Nid

Hi! In the rail were caps get hot I measured 21.7VDC and 0.04VAC from the rectifiers' output whereas in other rails (where caps don't get hot) the AC voltage was max 0.02VAC. These 40millivolts can't be the cause for heat in the caps, can they? Caps are within specs. Old caps were also getting hot in the particular rail. I don't think that there should be a higher current drawn from that rail than from the others (with same outputs) but I am not sure about that. It has same design but different components though. Should I replace the diodes? (current diodes are "standard recovery") Thanx, Nid.

hope someone checks this question out: Is it natural for a polarised aluminum electrolytic capacitor to get hot? What can the reasons for that be? I am not talking about small ones (let's say at least 4700uF @ 16V). Thanx!

thanx Ante. Is this stuff nice for cleaning reel-to-reel tape recorders' heads too? MP, what 0 ? If you mean the 0 at my rough drawing then this is the resistance at pins 2-3 at gang-1 and 1-2 at gang-2 ONLY when the pot is at the fixed center position. If I rotate it then the resistance rises with values from 0 to approx. 88K or 82K (depending on the gang).

Hmmm, if you mean acoustic levels I think about 2db max. My speakers were never out of phase, I mean for several years...hey I am a damned sound engineer. lol...not everyone is an audio guru. OK. Here I have in front of me 2 spray cans. Both Philips. One is the blue "DEGREASER CLEANER", the other is the red "CONTACT CLEANER". So, the blue should be good for cleaning e.g. connectors. The red should be good for cleaning pots. Correct? Yeah actually I am using graphite (in powder or spray can) for hinges too. I only used WD40 in the past. However I didn't know it was that "messy". I'll try to find and buy a "video drum cleaning spray". Is there a particular product I should check out? Now I am really curious...I need to get a WD40 and do some ghost-busting...Isn't there a chance it blows in your hands? ;D ;D ;D