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    old pcb connector name

    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...
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    DIY Power conditioner (for mains 230V)?

    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...
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    DIY Power conditioner (for mains 230V)?

    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...
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    DIY Power conditioner (for mains 230V)?

    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)...
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    How to make an audio console's power supply better?

    thanx indulis. please explain "inrush current". have you read the rest of the thread? It is a linear regulated psu. thanx again!
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    How to make an audio console's power supply better?

    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...
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    How to make an audio console's power supply better?

    Thanx Ante. I haven't done any mods yet...too much damned work...but I am going to start very soon.
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    How to make an audio console's power supply better?

    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
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    How to make an audio console's power supply better?

    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...
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    How to make an audio console's power supply better?

    ...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?
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    How to make an audio console's power supply better?

    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
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    How to make an audio console's power supply better?

    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...
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    How to make an audio console's power supply better?

    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!
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    Cleaning potentiometers

    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...
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    Cleaning potentiometers

    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...
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    Cleaning potentiometers

    audioguru I had done the following thing which I forgot to mention: I fed some line level inputs (the CD input if it matters) with a constant 1KHz sine tone from a PC pro audio interface. I measured the VAC at both channels right at the input and it was exactly the same amount of a few mVolts...
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    Cleaning potentiometers

    Hi! I am measuring out of circuit of course. Now I don't think that this pot has a wiper. In the center position there is a clearing on the carbon layer like there is no carbon there. I don't know if that is called a wiper. So here is a rough drawing to help you get the picture of what I am...
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    Cleaning potentiometers

    Hi! This is a 2-gang pot metal-shaft with a center click fixed position made by ALPS. Type 100KMN. It is used for the balance control between the 2 speakers. So when it is in the center position it should measure 100K for gang-1 and 100K for gang-2. However it measures 88K and 82K respectively...
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    Cleaning potentiometers

    Hi! I guess when the specs of a pot have changed there is nothing more you can do to save it, right? I am trying to refurbish an old 100K stereo pot. At its fixed center position it gives about 10K difference between channels, measured on its own (not on any circuit). After some cleaning I...
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    High grade pots?

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