Now he should tell us a bit more what is cooking, or, better, boiling before adding his preferred tea-bag
Say more, you bring luck, he just had his one side 15V working.
Yes, very nice and compact (even if I'm still puzzling if a smd/t.h. ultra compact version of the pcb can be made to squeeze it in tight spaces such as an existing product - i.e. a cdp - to upgrade it)
I saved the first layout image you published time ago as reference for future pcb drawings.
Unfortunately the C102-104 footprint doesn't looks big enough for 4.7uF MKP. I estimate something around 10 x 31.5 mm, p 27.5 mm on that pcb while a good MKP requires 22 x 41.5 mm p. 37.5 mm....
It is made with polyester 22.5mm pitch in mind since this Zobel adds much resistance and the loss factor is rendered irrelevant. So it remains compact also. But you define the calculated termination loss for the phase shaping you are after against variations and ageing of Ecaps that way. Checked with big boxes, it goes double width and broadens the layout negatively. Kemet (Rifa) MMK 10uF 63V and Vishay MKT1822 6.8uF 63V are very good. NOS ERO MKC 6u8 fits and is best, I prefer it to average box PP. To bring the Vref noise down to limit an Ecap is preferred for digital & MC at the filtering position, but a 10uF MKT has less distortion, so it can be interesting from line pre to MM apps hence the layout space for it there too. PP is not always the most exciting subjectively in industrial spec box caps. Some will still prefer a Muse or FC or SilmicII. Has a nice set of adaptation choices. Can even run on just average Ecaps for both filtering and termination, most economically. Has the pads, a jumper on R Zob, and Bob's your uncle. *Smt you can make, but you will not squeeze the dissipation needs. Sinks the same size.
Some will still prefer a Muse or FC or SilmicII. Has a nice set of adaptation choices. Can even run on just average Ecaps for both filtering and termination, most economically. Has the pads, a jumper on R Zob, and Bob's your uncle. *Smt you can make, but you will not squeeze the dissipation needs. Sinks the same size.
hello Salas
i have made today an ~ 60cm2 radiator from ~2mm aluminium sheet.the small radiator has ~ 25cm2.i coupled them toghether.so now i have around ~ 85cm2.the tempearute of the radiator raises to 50C in free air and 55-56C in case, this after half of hour of functioning.i expect it ro raise to ~60C in case, 10C lower than with the small radiator who had 70C measured in free air
i have made today an ~ 60cm2 radiator from ~2mm aluminium sheet.the small radiator has ~ 25cm2.i coupled them toghether.so now i have around ~ 85cm2.the tempearute of the radiator raises to 50C in free air and 55-56C in case, this after half of hour of functioning.i expect it ro raise to ~60C in case, 10C lower than with the small radiator who had 70C measured in free air
if i`ll drop 20ma there will remain only 90ma for the mosfets.you recommended 100ma
i`ll try to drop first 10ma and if the radiator doesn`t go below 50C(45-48 as you suggested) i`ll try then then to drop 15-20ma .
thanks again
Reliability comes first.
oops...forgot to tie the case shielding to the star ground.now is much much better.hum and noise are almost imperceptible.tested this with the input of the phono connected at the turntable and the volume on my tube line pre at maximum gain.
i also measured again the temperature on the radiator with case closed and i have got 51C and the temparature inside the case (point in the middle of the case) and it 40C
i have tested also the old ps which is a clasical transformer and the new one is switching ps.output voltages were set the same(old ps and new ps).
i don`t hear any difference between them
want to ask you one more thing.after what period of time should i adjust the output voltage ?
i also measured again the temperature on the radiator with case closed and i have got 51C and the temparature inside the case (point in the middle of the case) and it 40C
i have tested also the old ps which is a clasical transformer and the new one is switching ps.output voltages were set the same(old ps and new ps).
i don`t hear any difference between them
want to ask you one more thing.after what period of time should i adjust the output voltage ?
40C ambient in box looks pretty OK. Yes, the case shielding plays a big role for hum and should be grounded as you discovered. What output voltage to adjust? The PSU's one? You should check and adjust that after case is warm, opening, doing it fast enough, so to have it fixed for the real working temperature. 30minutes at work enclosed. Then you do it.
Today got some k-72 47nF russian teflons to change the FT-3 100n interstage capacitor.
Before that I also tried some Obligatos 47n, but these were no match to the FT-3.
I can say that I got much better dynamics, especially in the treble. Like a veil was lifted. Some would say that these may be a little hard on the treble, but this was not my impression. No hardness, but more resolution.
One caveat though. These things are BIG. I had hard time to make them fit to my board!
Before that I also tried some Obligatos 47n, but these were no match to the FT-3.
I can say that I got much better dynamics, especially in the treble. Like a veil was lifted. Some would say that these may be a little hard on the treble, but this was not my impression. No hardness, but more resolution.
One caveat though. These things are BIG. I had hard time to make them fit to my board!
