Hi
for working on first hit. 1. With weaker leds just find R1 value that satisfies the current that you were looking for. ICCS=VR1/R1. 2. 7.5mA is near enough in gain to 8-8.5mA, but weaker dB overall. Post various DC voltages like drains to earth, collector to earth, so we see the bias is still logical if the dB are enough total with your Sowter. If no danger, and dB enough, no worries. 3. Yes, GDS you put correctly. We will be happy to see it in box and learn how you like it in the long term. What you had before?Hi,
I have built:
N°2 TNT Indiscreto (one for mi friend),
N°2 VSPS of RJM (one for my friend),
N°1 Phonoclone 3 of RJM.
Now Riaa Phono stage Salas.
Do you have hum for now its not in box, no coaxial etc.?
P.S. You have no sinks on the regulator Mosfets I see, don't run it high current without.
P.S. You have no sinks on the regulator Mosfets I see, don't run it high current without.
I have slight hum because it is not in the box (to be considered also that some noise is normal with MC cartridge).
Yes, I have to add sinks to mosfet.
Good night.
Yes, I have to add sinks to mosfet.
Good night.
It can be made totally silent, has been done before. You will take care when in box, with final grounding etc.
Good night.
Good night.
azur mm pre to mm-mc
hi Salas, guys,
here are pics of my mod on azur 540 mm pre
not tried out yet though with my mc cartridge and I decided to use alkaline batteries after several attempts failed using existing regulator. Azur's positive rail always going down when MC is on...not good
200R trim-pot for R1 and R5 under the board. Salas I keep the 1000uF caps, is this ok or do I still have to use BC550?. Please let me know if you have better ideas.
thanks (sorry for poor pics)
TeguhPS
hi Salas, guys,
here are pics of my mod on azur 540 mm pre
not tried out yet though with my mc cartridge and I decided to use alkaline batteries after several attempts failed using existing regulator. Azur's positive rail always going down when MC is on...not good
200R trim-pot for R1 and R5 under the board. Salas I keep the 1000uF caps, is this ok or do I still have to use BC550?. Please let me know if you have better ideas.
thanks (sorry for poor pics)
TeguhPS
Attachments
Its OK, just runs lower currents, its safe. If your gain is enough with step up, don't bother changing the Jfets.
I explain, to find the current that the reg runs in CCS, you divide what voltage you have on R1 (green fat one), by R1 in Ohm. So if it is below target, one way is not to use stronger LEDS (make more V across R1) but to use smaller R1.
Not 470 Ohm, but 4K7 because 6mA = 0.006A. But it is going to be +0.6V, there is transistor's Vbe under it also.
I explain, to find the current that the reg runs in CCS, you divide what voltage you have on R1 (green fat one), by R1 in Ohm. So if it is below target, one way is not to use stronger LEDS (make more V across R1) but to use smaller R1.
Not 470 Ohm, but 4K7 because 6mA = 0.006A. But it is going to be +0.6V, there is transistor's Vbe under it also.
R5=220K terminal resistor, not 200R trimmer. You have to use 550, it sets the voltage lower also. Plus, its not going to play long on batteries. 14mA bias.
There is an error in your PDF
(Use R=V/I and P=V*I, to compute the value of your load resistor for testing your shunt.
Where V is the output voltage of the shunt and I is the consumed current. (If you are going to use one
shunt for both channels then I = 0.06 A).
No, now I see its I was talking the Vref resistor and you were talking the dummy load. You are OK.
Try 250mA fuse first, and if it blows (depends on Tx regulation and capacitor volume & ESR) go higher step by step until is not blowing during on.
Yes new longer listening session & your very good tweak/advice getting off the resistor & capacitor is a very huge upgrade, remember me near the same subjective than getting off the cap in the 1st stage but the cap in the 1st stage was still worse. Output caps Mundorf Silver Gold in oil are very very transparents so I can hear very easy the differences to god or bad.
😉