Salas has awesome reputation with his boards as his prices halas... K&K despite being dollars are more affordable for my poor monney. (well I know, if no monney stay away from tubes...) . Of course I will switch on the first time with a cheap brandnew ECC88, not with the good rare NOS, three ninjas already tried to steal !
at euro21, well maybe a soft start is less expensive than a burn out therapy because the rare tube smoked... that's what I say to myself while 2 kilos of chocke is something too !
at euro21, well maybe a soft start is less expensive than a burn out therapy because the rare tube smoked... that's what I say to myself while 2 kilos of chocke is something too !
You mean both for the heater and B+ ? It even doesn't affect the span life or number of switch on/off with SS diodes rectifier ?
Main here is 240 V with sometimes 260 V peaks.
I assume the 25w serie resistor after the full bridge in Rod Colman post is here also for such inrush and also keep the bridge safer at switch off?
As far you say it is safe for my E188CC and I should not care I trust you guys.
I assume the 25w serie resistor after the full bridge in Rod Colman post is here also for such inrush and also keep the bridge safer at switch off?
As far you say it is safe for my E188CC and I should not care I trust you guys.
The underheating/overheating filament (both IDH and DH) is may more degrade -small- tube lifetime, than "cathode poisoning".
So if you want to shield small tubes, rather use regulated filament DC PSU -even pure fix voltage LDO- than soft start.
So if you want to shield small tubes, rather use regulated filament DC PSU -even pure fix voltage LDO- than soft start.
I like voltage regulated heaters (IDHT) because you can substitute different tubes from the same family (ie 6DJ8 v 6922) without any adjustment.
No harm in soft-start heater, ref TI LM317 datasheet (Fig 19) - just a few extra dollars.
Sure. Picture RC filter, then replace R with CCS.
Unlike Salas SSHV reg from Post #160 (I cant copy/edit the post to here), the DC load current is determined by the CCS and differs in that the shunt does not pass DC current (its a capacitor). So for example you can set up a triode in constant current operation, without loading it with a CCS.
Last edited:
Thanks for the ref of fig 19.
This gentleman made gerbers with lm317 and denoizator from Elvee member clever work https://www.diyaudio.com/community/...grade-any-317-based-v-reg.331491/post-6942943.
not really HV though so off topic, sorry to the op for my digress about diode rectification and heaters.
Let us continue the good thread about Sic vs Vacum rectification.
This gentleman made gerbers with lm317 and denoizator from Elvee member clever work https://www.diyaudio.com/community/...grade-any-317-based-v-reg.331491/post-6942943.
not really HV though so off topic, sorry to the op for my digress about diode rectification and heaters.
Let us continue the good thread about Sic vs Vacum rectification.
One other way to do it is a hybrid or Graetz bridge. Tube for the positive side and diodes for the negative side. I've used this a lot, and when I swapped in the SIC diodes for UF4007 it did sound s little smoother to my ears. Good way to do it if you have no centre tap on the secondary winding.
yes, i do this all the time, simplicity and functionality, just two secondary wires instead of 3, lower voltage on the traffo secondary, what is not to like?
There is no significant difference in the end result between tube full wave and hybrid rectifying.
The SS graetz means a more problematic load on primary, because the diodes opening angle is much narrower.
The SS graetz means a more problematic load on primary, because the diodes opening angle is much narrower.
It's significant, if anybody want to make own EI or M core PT, where fill factor is limited.
It's almost incidental circumstance (only depending of the price) if you develop a PSU.
The required power is the same, so core parameters are almost the same in both cases, only copper wire and winding cost is different.
It's almost incidental circumstance (only depending of the price) if you develop a PSU.
The required power is the same, so core parameters are almost the same in both cases, only copper wire and winding cost is different.