The sim gives similar DC results to what you get for 196V AC & 54R secondary resistance
Hi Salas,
finally, I combine two 82 ohm 2W resistors in parallel found in the parts bin and now I set the V-Out to 260V e the I-Out to 20ma
Is the resistance value too small?
finally, I combine two 82 ohm 2W resistors in parallel found in the parts bin and now I set the V-Out to 260V e the I-Out to 20ma
Is the resistance value too small?
No, I wouldn't say uselessly small, its doing some useful filtering still. If you will need more mA CCS for the preamp its another thing. You will be forced to lower the R even more. Even little is good for at least opposing rectification's EMI. In general to be on the safe side, when buying HV rail transformers for future projects use ballpark calculation for expected DC=ACx1.3. If proving some excess you can burn it on R, if proving short due to losses you can't do something.
Thanks Salas,
My fault, in this case, is DC=ACx1,4.... for the future DC=ACx1.3
Now, I'm waiting for Salas SSLV1.3 Ultra-BIB Tea Bag already send to me I need for 12.6 and 6.3 and ready to go 😀
My fault, in this case, is DC=ACx1,4.... for the future DC=ACx1.3
Now, I'm waiting for Salas SSLV1.3 Ultra-BIB Tea Bag already send to me I need for 12.6 and 6.3 and ready to go 😀
It has 200V secondary between Rosso Nero. Has 400V between Rosso Rosso. Confirm with ACV meter 200V between one red and the black. Be careful not to accidentally touch the naked end of wires when measuring. Bianco is 0V for heaters.
This is 220V primary transformer, so secondary would be 213.6V AC (at 235V input).
With this transformer you are in the low side of raw supply voltage.
With this transformer you are in the low side of raw supply voltage.
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Little bit over 1.1 AC ratio when unloaded. Better without center tap, quad bridge to save on peak inverse voltage across the diodes IMO.
CCS headroom (in SSHV2) is at least 10-30V (I prefer 30V, there FET's CrSS capacitance is enough low), so raw DC voltage would at least 270-290V (for 260V output).
At least 230-240V AC.
You must calculate current loading too.
If you want to use 2 x SSHV2, the raw PSU load current is 2x (shunt current + load on 260V/channel).
In the photo my preamp,
as Salas told me, 10mA for one 12AU7 section, two 12AX7 sections, one 6DJ8 section are enough.
I have two SSHV2 but since one delivers 100ma but I thought I would use only one, for the rest I will use Salas SSLV 1.3 Ultra-BIB.
For now, I try with the transformer at my disposal, but I do not rule out buying a better one, for this I asked for advice and where to take it to buy
as Salas told me, 10mA for one 12AU7 section, two 12AX7 sections, one 6DJ8 section are enough.
I have two SSHV2 but since one delivers 100ma but I thought I would use only one, for the rest I will use Salas SSLV 1.3 Ultra-BIB.
For now, I try with the transformer at my disposal, but I do not rule out buying a better one, for this I asked for advice and where to take it to buy
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So we guessed about the preamp's mA needs. Remains to see. One SSHV2 delivers "up" to 100mA. You set the limit by CCS setting. Since you are short for spare voltage on the transformer for now, set the SSHV2 CCS conservatively not to lose much voltage on the CRC filter. Much spare current has strong impact on the regulator's sink temperature also. See the SSHV2's pdf manual about details. For heaters power a very good efficient enough solution is also the L-Adapter.
SSLV 1.3 is very good. But if too good for just heaters why not use it where it counts more after evaluation. Has a CCS so it will heat two semiconductors M1 M2 (mostly M1 for heaters) when L-Adapter has just one big bipolar pass element to sink.
This type preamps need ca. 15-20mA / channel, so with 25-30mA shunt current the power supply load is ca. 50mA /channel.
One SSHV2 (90-100mA) is also OK for both channels.
Lite Audio suggest 7815 and 7806 (7805 and and one diode from reference pin to ground) stab. for heaters.
http://www.lite8.com/product.php?action=723
p.s. Using shunt stabilisers for indirect heater is a luxury category, totally unnecessary.
One SSHV2 (90-100mA) is also OK for both channels.
Lite Audio suggest 7815 and 7806 (7805 and and one diode from reference pin to ground) stab. for heaters.
http://www.lite8.com/product.php?action=723
p.s. Using shunt stabilisers for indirect heater is a luxury category, totally unnecessary.
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