The schematic in the SuperReg instructions shows an LED in the shunt leg, but Allen replaced it in due course with a miniature filament bulb for better reliability.
Here is the part supplied with my SuperReg kit: https://www.buerklin.com/en/p/-/light-bulbs-lamps/21331480/32G672/
Alex
Here is the part supplied with my SuperReg kit: https://www.buerklin.com/en/p/-/light-bulbs-lamps/21331480/32G672/
Alex
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I managed to get this regulator to work but the led light is kind a blinking like going on and off. If I measure test point 2 then voltage is jumping from 0.0 - 0,1 V. Turning trimmer seems also not changing LED blinking. Q2 mosfet is getting hot without load also. It is probably affected about this that I have to do voltage dropdown 115 volts. I am using it to power on FVP5 which requires 200 volts. Can I lower somehow this this dropdown by adding some resistor before or after regulator? Something better way to do this?
Any thoughts how to stop LED blinking?
My FVP5 mosfets get quite hot after 2-3 minutes on and also tube. Is it normal? Does this Superreg affects it because the led is blinking and something is off? I have bulb 14V and 80mA to change it later replacing the LED.
No sound check have done yet.
HV PSU has 4,7k resistor 10W between 150uF caps. Output 315V.
FVP5 - R1 not in use. Input 200 volts.
Any thoughts how to stop LED blinking?
My FVP5 mosfets get quite hot after 2-3 minutes on and also tube. Is it normal? Does this Superreg affects it because the led is blinking and something is off? I have bulb 14V and 80mA to change it later replacing the LED.
No sound check have done yet.
HV PSU has 4,7k resistor 10W between 150uF caps. Output 315V.
FVP5 - R1 not in use. Input 200 volts.
For the load I built FVP5 (do not know yet if this FVP5 is working) using 6N23P tube and then the Superreg led is blinking. FVP5 one of the mosfets U2 get really hot in a 5-10 seconds another mosfet U3 is cool. What could be the cause? Is this my posted FVP5 schematic correct? U2 connected to the pin 8? I am using Nichicon UES 25uF bi-polar cap.
What would be a good resistor value to add as load for this regulator?
What would be a good resistor value to add as load for this regulator?
I managed to fix the led blinking. I forgot to do some modifications. But in FVP5 pcb mosfet U2 get hot in 10-20 seconds. A really hot hot. J3 terminal is feed with 15V in that goes to U2 gate through resistors. What I am doing wrong or where I should look like? I changed tube for another 6N23P and still. I am using for testing purpose cheap Chinese adjustable 15W DC regulator OKY3502.
Voltage on pin 8 is 82,5V and on pin 7 about 79V. Voltage between on R7 is 11,5V. Input voltage 206V. Voltage on superregulator test TP2 is 9,7mV under load when connected with FVP5. Without load is voltage on Superreg TP2 154mV. I do not know how to measure current through tube as the voltage drop across R7.
The voltage drop across R7 looks OK, it is +15V minus around 3.5V to turn on IRF710/U2 on about 9.5mA, looks OK.
Pin 7 and +79V looks what I would expect and likewise Pin 8 a few volts higher.
As you have got +206V rail, then (206-79)/25K = 5.08mA, that OK too.
That current gets split up, 1.7mA through 47K and 3.4mA through gain tube.
That means that if you check Pin 3, then the voltage across R3 will be 2200*0.0034mA = 7.48V, can you check that?
Check voltages on Pin 1 (+79V), Pin 2 (0V), Pin 3 (7.68V) and see if they are those?
Can you also put a test voltage through it and watch on a scope? Does it work and is it stable?
PS: The TP2 test point, is it 1R to ground, or is it 10R?
PPS: I can point to an improvement that can be made to the circuit, use a current source set to 3.4mA instead of that R5 47K.
Pin 7 and +79V looks what I would expect and likewise Pin 8 a few volts higher.
As you have got +206V rail, then (206-79)/25K = 5.08mA, that OK too.
That current gets split up, 1.7mA through 47K and 3.4mA through gain tube.
That means that if you check Pin 3, then the voltage across R3 will be 2200*0.0034mA = 7.48V, can you check that?
Check voltages on Pin 1 (+79V), Pin 2 (0V), Pin 3 (7.68V) and see if they are those?
Can you also put a test voltage through it and watch on a scope? Does it work and is it stable?
PS: The TP2 test point, is it 1R to ground, or is it 10R?
PPS: I can point to an improvement that can be made to the circuit, use a current source set to 3.4mA instead of that R5 47K.
I checked the voltages. Pin P3 - 7,89V, P2 - 0,05V, P1 - 76,7V. Test point TP2 is 10R to ground.
I do not have scope.
Still mosfet U2 gets hot and no sound through FVP5 input from soundcard headphone out. Could be tube issue?
Could you please point me some current sources? I do not have much education about that.
I do not have scope.
Still mosfet U2 gets hot and no sound through FVP5 input from soundcard headphone out. Could be tube issue?
Could you please point me some current sources? I do not have much education about that.
Itube and Mosfets = 11,5V / 1200 = 9,6mA
Power dissipation on lower Mosfet U2 is (82,5V - 11,5V) x 9,6mA = 0,68W
Without a small radiator it is normal to be very hot
This Mosfet of course replace the cathode follower cathode resistor so it is normal to dissipate some heat . The plate Mosfet U1 has a much less voltage drop so it will stay cool
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Yes re U2, it can get quite warm at 0.68W, so this is not an indicator there is something wrong with the operation of the circuit. It's borderline OK without heatsink.
Best to get it working first.
Then talk about how to implement current source afterwards, to replace R5 47K. Others here on the thread might be interested in this implementation, how to do it and why to do it.
But so far your voltages all seem to be within the ballpark expected. This is why a signal generator and a scope would explain what is happening to the AC (signal) voltages and whether you are even getting a signal on the input?
Can you try another source other soundcard?
I replaced U2 with another bigger heatsink. Now the temperature is manageable. I tried audio from the iPhone, signal generator REW through computer and nothing. I measured AC voltages in input without any source connected 6,8 V AC and output 5,7 V AC. Should be like this? Input connected to audio from computer then input AC shows 36 V and output 42 V. I am using only one channel. If I get it to work then I will build another one. iPhone audio out shows 0,2 V AC measured separately not connected with nothing.
I will add my pcb. Maybe is something wrong with that? GND is connected with everything every source, psu together? Right now heater has separate gnd but PSU board is the same for two DC regulators for 6,3V and 15V.
Any thoughts?
I will add my pcb. Maybe is something wrong with that? GND is connected with everything every source, psu together? Right now heater has separate gnd but PSU board is the same for two DC regulators for 6,3V and 15V.
Any thoughts?
I discovered that in my output 6.3mm pcb mounting jack plug socket was faulty. So it could not pass trough any sound to my amp. I changed it and I tried it again. Now I have enormous high voltage regulator noise in the output. Could be the Super Reg issue or something with my tube? Allen regulator output is 200V and test point voltage is 0,2 V.
Any thoughts and help is really appreciated.
Any thoughts and help is really appreciated.
My schematic is with IRF710 mosfets and called FVP5 (200V version) one tube not FVP5A (250V version) with a two tubes line out. If I turn Super reg off then the noise goes off from the speakers. So it comes from FVP5 preamp output. I do not have oscilloscope or other equipment and knowledge to dig deeper. I made also FVP5A and there is the same issue that voltage regulator noise hits the speakers so loud and if I measure output then its about 10-20 V maybe sometimes more. How can I check if the tube is ok and working?
My FVP5A schematic 250V version. If someone could check it if everything is OK specially U2C and the tubes connections with each other. J5 is used separate 20V supply. Same issue that regulator noise is so loud at output and input has also big voltages somehow.
I made also FVP5A and there is the same issue that voltage regulator noise hits the speakers so loud and if I measure output then its about 10-20 V maybe sometimes more. How can I check if the tube is ok and working? My FVP5A schematic 250V version. If someone could check it if everything is OK specially U2C and the tubes connections with each other. J5 is used separate 20V supply. Same issue that regulator noise is so loud at output and input has also big voltages somehow.
On the topic of the original FVP Line Stage using SLCF output buffer, I know that I might get into trouble saying this, but the final design was totally due to the fact that I convinced Allen to drop the SRRP route. There are witnesses to this fact, such as Thomas Bruentrup, Allen's personal technician who is still around. This also influenced how Allen set of the Line Stage in the RTP variations. I am simply pointing to history.
I only mention this because the FVP-6 that I use now, in the sense that FVPs come back here and get their upgrades, we are talking here in Australia of course. But in the FVP-6 we have gone over to a new tube, not the 6DJ8/ECC88/6922, but the venerable 12AT7/ECC81 and this may surprise some. The filaments in the 12AT7 needs to be wired in series and +12.6V - but of course, depending on what power supply you are using now, also use 6.3V AC. The 12AT7 is sweet sounding and more transparent in the FVP circuit than the 6922 we have used. I have done about a dozen of them, maybe a few more, and nobody has come back and wanted it back to what it was.
So is there any interest, since we are talking FVPs?
I only mention this because the FVP-6 that I use now, in the sense that FVPs come back here and get their upgrades, we are talking here in Australia of course. But in the FVP-6 we have gone over to a new tube, not the 6DJ8/ECC88/6922, but the venerable 12AT7/ECC81 and this may surprise some. The filaments in the 12AT7 needs to be wired in series and +12.6V - but of course, depending on what power supply you are using now, also use 6.3V AC. The 12AT7 is sweet sounding and more transparent in the FVP circuit than the 6922 we have used. I have done about a dozen of them, maybe a few more, and nobody has come back and wanted it back to what it was.
So is there any interest, since we are talking FVPs?