Wooden chassis is fine as long as the warm air from the shunt regs can circulate and get out. (in other words - holes needed...) Plus, the shielding from a metal chassis is always a good idea, in order to avoid hum and noise.
Speeding up the servo is possible, reduce C5 (1uF) down to maybe 470nF or 100nF - I wouldn't do faster as then the servo is cutting into the LF audio signal, and that may not be what you want.
The buffer heatsinks are overdimensioned in the original design, and even bigger in SQ's design, pretty sure they don't get hot.
Speeding up the servo is possible, reduce C5 (1uF) down to maybe 470nF or 100nF - I wouldn't do faster as then the servo is cutting into the LF audio signal, and that may not be what you want.
The buffer heatsinks are overdimensioned in the original design, and even bigger in SQ's design, pretty sure they don't get hot.
21 so far Alfred. Lots of happy friends and acquaintances.
That pic is slightly out of date, it's now just LCR styrene caps in the RIAA, no wimas to pad out the pF. Took a while to get a perfect match. Rushonline in the UK has them.
Garf, no they never get warm, the main heatsink gets warm, but not too hot, and that's with the 8.2ohm in the shunt to get the last 30mA for the Calvin boards.
That pic is slightly out of date, it's now just LCR styrene caps in the RIAA, no wimas to pad out the pF. Took a while to get a perfect match. Rushonline in the UK has them.
Garf, no they never get warm, the main heatsink gets warm, but not too hot, and that's with the 8.2ohm in the shunt to get the last 30mA for the Calvin boards.
After a long delay, I am now getting back into building mine. All resistors are mounted, just transistor matching and populating the rest of the PCB left to do. Are all of the tweaks and modifications along the way to tame oscillation, etc., included in Hesener's latest project documentation?
Thanks!
Thanks!
Calvin
I have a cored one in mine too...should it just be air cored?
Sent from my SM-G930F using Tapatalk
Nah, plastic core to wind over. I've since gone all big with some proper wound cores from an OEM.
Hi, I'm putting together my paradise, I have the pre-regulator with a 2x24V that unloaded it is 28v, once I connect the regulator the voltage drop to 21,6V and the led on the back don't shine. If I want to see the leds on I have to raise the main to 245 and so I have 23,6V on the regulator, I have to change the transformer?
Giorgio
Giorgio
So you are saying they are outputting 26.5vAC on the secondaries, unloaded?
If so, how can they only give 28v DC if the circuit is unloaded? should be approx 26.5*1.414, which is ~37.5V.
I think my regs did output approx 40vDC unloaded when i measured long ago...
And loaded with the paradise boards the output from the pre-regulators have been between 25.5 up to approx 28v (depending on mains variations between 220v up to 238v).
If some of your resistords in the pre-regulator boards drops to much, then just lower their value and you'll be fine..
i did lower the last 10R resistor to 6R just to get a little more headroom when the mains drops to about 220vAC.
If so, how can they only give 28v DC if the circuit is unloaded? should be approx 26.5*1.414, which is ~37.5V.
I think my regs did output approx 40vDC unloaded when i measured long ago...
And loaded with the paradise boards the output from the pre-regulators have been between 25.5 up to approx 28v (depending on mains variations between 220v up to 238v).
If some of your resistords in the pre-regulator boards drops to much, then just lower their value and you'll be fine..
i did lower the last 10R resistor to 6R just to get a little more headroom when the mains drops to about 220vAC.
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So... loaded the regulator outputs +-21.6VDC? and input voltage is 26.5VAC?
Unloaded the regulator outputs 37VDC, and input voltage is how much AC?
what current is the CCS on the paradise set to?
Have you tried loading the pre-regulator with resistors instead of the boards to approx paradise psu CCS-current? Then measure output voltage... that way i would start, because then you can see if the problem is within the Pre-reg or the paradise...
Unloaded the regulator outputs 37VDC, and input voltage is how much AC?
what current is the CCS on the paradise set to?
Have you tried loading the pre-regulator with resistors instead of the boards to approx paradise psu CCS-current? Then measure output voltage... that way i would start, because then you can see if the problem is within the Pre-reg or the paradise...
Patriz, Please list all the parts in your psu, transformer, in/out voltage and VA, diodes, caps chokes etc.
A standard psu build based around the group buy psu specification and using Hammond 158T 1H chokes, (300mA) needs to output about +/-39v DC unloaded to deliver about 26v when loaded.
It sounds to me like your transformer VA may be too low.
I still have transformer and rectifier smoother boards for a full PSU build if you need them.
A standard psu build based around the group buy psu specification and using Hammond 158T 1H chokes, (300mA) needs to output about +/-39v DC unloaded to deliver about 26v when loaded.
It sounds to me like your transformer VA may be too low.
I still have transformer and rectifier smoother boards for a full PSU build if you need them.
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Hi, Vac is the same 26,5 loaded or unloaded with the regulator, all the measurament are with the phono not connected, just the regulator. The regulator absorb 127mA.
Giorgio