to minimise the loop area of that long loop
This is what I made for my BHL Phono amp. Please correct my drawing if you see something wrong in it.
Please note, this is not a Folded Simplistic.
if one connects the returns at the Source and one also has the returns connected somewhere downstream, then one has created a very long loop. That loop is very likely to have problems with picking up interference.
Recently I can across a dual coax with the screens in contact. That would be one way to minimise the loop area of that long loop.
I have never seen any project describe how to avoid this stereo source to stereo receiver loop.
There are a couple of papers that describe methods of reducing the current in these loops.
This is what I made for my BHL Phono amp. Please correct my drawing if you see something wrong in it.
Please note, this is not a Folded Simplistic.
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The DIYA store has many adequate boxes lately:
Compact with Quasi Heatsinks - Chassis
Compact with Quasi Heatsinks - Chassis
The folded one? For MM or MC? Any pics?
I see you placed 7809 regulator with BC550C NPN transistor for MC PCU in your yearly manual. Do you prefer 78XX over LM317T? Why? LM317 has lower noise and higher ripple rejection. Please let me know.
I did not care since a capacitance multiplier followed in that pre-pre case, so the 78xx was chosen for simplicity. LM317 with adj. pin AC decoupling cap is superior to 78xx when alone. But what it has to do with the quoted post?
It was my mistake to include that quote.
Can you explain what BC550C is doing there. What it is for?
If I use LM317T, then do I need to add that transistor to the circuit?
If yes, can I use BC547C instead (I do not have BC550C)? It is the same beside noise is little higher.
Thank you.
Some difficulties making the kmultiplier work with the usual 4 pole smoothing caps (oscilations maybe)... I tryed with "normal" Elna 10000uF and found no gains relative to my "normal" RC concept.... the V12R are quite good in psrr so I will keep it simple now
The less circuitry the better if making no audible contribution.
I will make one such raw rail active filter to test it myself with other reg versions at a point too maybe.
It was my mistake to include that quote.
Can you explain what BC550C is doing there. What it is for?
If I use LM317T, then do I need to add that transistor to the circuit?
If yes, can I use BC547C instead (I do not have BC550C)? It is the same beside noise is little higher.
Thank you.
Its a pre-pre and that transistor has a capacitor there that multiplies its value by the gain so to filter the regulator's noise because its a very sensitive signal level and there is no cascode. BC547C will do fine.
There was a short thread with builds even for that pre-pre from the older pdf.
http://www.diyaudio.com/forums/analogue-source/188730-2sk170-bl-mc-step-up-amp-5.html#post2606756
http://www.diyaudio.com/forums/analogue-source/188730-2sk170-bl-mc-step-up-amp-6.html#post2723587
Its a pre-pre and that transistor has a capacitor there that multiplies its value by the gain so to filter the regulator's noise because its a very sensitive signal level and there is no cascode. BC547C will do fine.
There was a short thread with builds even for that pre-pre from the older pdf.
http://www.diyaudio.com/forums/analogue-source/188730-2sk170-bl-mc-step-up-amp-5.html#post2606756
http://www.diyaudio.com/forums/analogue-source/188730-2sk170-bl-mc-step-up-amp-6.html#post2723587
I made BC547C addition to my LM317T PSU with 2 Elna RFS caps, but noise got increased. Please see attached schematics. Did I make mistake somewhere there?
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