Kuartlotron Error Correcting Super Buffer

[avesbilal]

How much gain does this has, if it doesn't has any gain, is there a possibility to have gain in this to get some desired output from power amp?

 

[jls001]

Unity gain buffer. Unless you have a source with unusually low output voltage level, most sources can work perfectly without preamp stage to boost level. I'm guessing it will work well in your setup too

 

[saheb11123]

I will contact mr sachin in a few days.
Do I need to pay advance or directly once it is ready to be shipped?

 

[keith_correa]

Guys - please wait for a new thread to be created by Sachin specifically for a GB IF at all there is going to be a GB run by Sachin. Let's keep clutter to the minimum here.

 

[avesbilal]

Sorry if this is a Novice question, Can I use a PS board based on regulators LM317, 337 with this buffer, like shown in the below PIC, I am also attaching the schema

 

[omishra]

^^yes, you can use it.

Eye Candy -

 

[sachu888]

HI Om,
it looks very good now:thumbsup:

Regards
Sachin

 

[doors666]

d1-r2 and d2-r13 are shorting, not sure if its intentional as you havent posted the schematic and i dont see any diodes in the original schematic.

 

[omishra]

d1-r2 and d2-r13 are shorting, not sure if its intentional as you havent posted the schematic and i dont see any diodes in the original schematic.

Thank you for your concern.
Yes its not in the original schematic and D1, D2 connected base-emitter of concerned transistors.
D1 & D2 - 1N4148 are from optional list when leak current of Q1 and Q3 could not start Q2. This is mentioned in trouble shooting list. So I added this in schematic. If anyone requires then it can be used.

 

[baswamin]

Om, one more request. Can you give more space for the 2uH inductor if some one wants to use the type which Joshua has used? It has a larger footprint and may be providing some more space will be useful.

Thanks

 

[omishra]

Actually you will get 1A axial 10-12mm specs fixed inductor which looks like 0.5W resistor size. Sachin is providing that. It costs rs30 each on element 14. Locally i remember it costed me 10Rs each.
Still let me know dimention, i would put it.

 

[jls001]

Inductor dimensions are pin pitch/separation 8 mm, barrel diameter 10 mm, barrel height 15 mm. Thanks.

 

[omishra]

Inductor dimensions are pin pitch/separation 8 mm, barrel diameter 10 mm, barrel height 15 mm. Thanks.

Thanks
i think Sachin ordered the PCBs. Still it can be accommodated in next batch if any.
What about drill 0.8mm or 1.0mm?

 

[quad]

Apologies for the late reply: inductor dimensions are pin pitch/separation 8 mm, barrel diameter 10 mm, barrel height 15 mm. Thanks.

It should be possible to use those inductors on the board,
though may not be a neat fit.

 

[saheb11123]

Or maybe wire the inductors outboard?

 

[omishra]

Or maybe wire the inductors outboard?

Now in the last iteration I added more space around inductors. So space is not a problem, only holes are issue now. Either paste that inductor upside down on PCB and solder little wires from hole or mount it horizontal and soldering small wires. Wires from leftover component legs could be used.

 

[jls001]

What about drill 0.8mm or 1.0mm?

Diameter of the inductor legs measure from 0.69 mm to 0.71 mm. So I think 0.8 mm holes will do fine.

 

[jls001]

The noise I've been experiencing is partially or fully coming from my power supply. I made a wall separating the transformer and OPS power supply board on one side and the buffer circuitry and all input, output and volume control wiring on the other side. The separator is a 2 mm aluminium sheet cut and bent to fit the components already fitted in place. The only wire that runs through this 'firewall' is the +/- 10 Volts supply from the OPS to the buffer board, through a tiny opening just big enough to let the three wires pass through. This brought down the self noise substantially. Later, I discovered that my transformer is vibrating a lot. It can be felt when placing the palm on top of the cabinet top cover. So I guess the next step is to use a better transformer. I usually use R Core but this time in my hurry to gather all parts I bought a ready made EI. It wasn't that cheaper than my usual custom ordered R Core, but it has so far turned out to be substandard. Two more lessons learned Now I understand why transformers are potted in damping material.

 

[omishra]

The noise I've been experiencing is partially or fully coming from my power supply. I made a wall separating the transformer and OPS power supply board on one side and the buffer circuitry and all input, output and volume control wiring on the other side. The separator is a 2 mm aluminium sheet cut and bent to fit the components already fitted in place. The only wire that runs through this 'firewall' is the +/- 10 Volts supply from the OPS to the buffer board, through a tiny opening just big enough to let the three wires pass through. This brought down the self noise substantially. Later, I discovered that my transformer is vibrating a lot. It can be felt when placing the palm on top of the cabinet top cover. So I guess the next step is to use a better transformer. I usually use R Core but this time in my hurry to gather all parts I bought a ready made EI. It wasn't that cheaper than my usual custom ordered R Core, but it has so far turned out to be substandard. Two more lessons learned Now I understand why transformers are potted in damping material.

Yes, almost all of failed preamps and phono preamps are due to bad power supply or noisy transformer. I tried orientation of transformer also matters where no parts or PCB coming in direction of axis of transformer coil. i.e. direction perpendicular to top surface of EI transformer. Likewise joint were E and I meet, these leak more magnetic flux to disturb other sensitive circuit. To get 100% silence, layout also plays role.

 

[Project16]

That guy is genius.

:signthankspin: