Thanks Nick
Can you remind me the Voltage divider to go from 2V RMS to ~0.3mV to make some measurements on the circuit?
Can you remind me the Voltage divider to go from 2V RMS to ~0.3mV to make some measurements on the circuit?
A ratio circa 6000 would be needed. So an L pad of 62K in series and 10 Ohm to ground would do. That's 6210.
Correct orientation and transistor type for Q3y position
If only my build time was as fast as your response time.
D1x
Ok, I tested an installed all led’s ( along time ago), all but dx1. Can’t find the paper with the values listed from when tested. Can you please advise d1x value? Also how do I test again? Something to do with 9 v battery and R ��.
Thanks So much!
Ok, I tested an installed all led’s ( along time ago), all but dx1. Can’t find the paper with the values listed from when tested. Can you please advise d1x value? Also how do I test again? Something to do with 9 v battery and R ��.
Thanks So much!
Go back to post one here and click the third link. It will take you to the PDF instructions. There is a paragraph in the notes section named LEDS.
P.S. Notice that if your own LED strings don't exactly reach the total forward drop voltages quoted in the instructions its not a problem, you just want them strings total voltages fairly well matched between the channels. Since the rest are already done and installed in in your case except D1x just match two reds for D1x to complete the PSU circuits.
Ok will match 2 leds pronto.
Next question, R2 and R3. I have a dl103r, so will need to set for 60db gain? I don’t have any IDSS info listed, foolishly misplaced. I would guess around 11 mA. Working from the PDF, 3.9 ohms would be correct?
Next question, R2 and R3. I have a dl103r, so will need to set for 60db gain? I don’t have any IDSS info listed, foolishly misplaced. I would guess around 11 mA. Working from the PDF, 3.9 ohms would be correct?
Hi Nick
I put the Phono in a carton box with adequate ventilation just to simulate the aluminum box will be in the near future so to adjust the TP1-TP1 bias
I see that even in the box the bias is raised slowly but in a continuous way up to maybe over 4Volts, and some time i do have to re-adjust VR2x to the limit and still can't go lower enough to 3.6V, I also use VR1 to lower the voltage but still raise slowly but continuous.
From cold start I see that it may takes an hour or more to reach 3.5-3.6V (without re- adjustement from previous session it starts cold from 1V or less and gradually raise to 2-3V in a hour or so).
I wonder if I put a plastic cover over the two K369s to isolate them (in a way) from the enviroment which is getting warm from the Power Supply Heat
Any ideas?
I put the Phono in a carton box with adequate ventilation just to simulate the aluminum box will be in the near future so to adjust the TP1-TP1 bias
I see that even in the box the bias is raised slowly but in a continuous way up to maybe over 4Volts, and some time i do have to re-adjust VR2x to the limit and still can't go lower enough to 3.6V, I also use VR1 to lower the voltage but still raise slowly but continuous.
From cold start I see that it may takes an hour or more to reach 3.5-3.6V (without re- adjustement from previous session it starts cold from 1V or less and gradually raise to 2-3V in a hour or so).
I wonder if I put a plastic cover over the two K369s to isolate them (in a way) from the enviroment which is getting warm from the Power Supply Heat
Any ideas?
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You could try a cover or to swamp them with a hot melt gun. Anyways you only look to keep an equidistant point they would hover about because MC version input stage may drift but still keeps enough DC voltage window to contain the few decades of mV level signal swing.
Its fine. Even more +/- TP1-TP2 DCV allowance between cold start and well warmed up would not be disastrous.
John try 18 Ohm R2 source resistor to your 10mA IDSS K369 Q1 input stage along with a 3.3K 1W R13. Q2 R3 not populated. You should get the middle ground 50dB gain you require.
Circuit Description
Hi Salas, Is there a circuit description for the FSP like the DCG3 thread post #47?
I’ve been trying to better understand how this circuit works. I’m loving this project and very happy I’m finally getting back into the hobby.
Many thanks as always, for all your knowledge and support
Ps: I’m slowly getting through the 1600 + pages of this thread.
Hi Salas, Is there a circuit description for the FSP like the DCG3 thread post #47?
I’ve been trying to better understand how this circuit works. I’m loving this project and very happy I’m finally getting back into the hobby.
Many thanks as always, for all your knowledge and support
Ps: I’m slowly getting through the 1600 + pages of this thread.
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