Seems to be ok in test. Acted as you said, the voltage dropped a bit at first.
I have a 10K test-resistor. At 180V this gives me like 18mA trough it and 18mA shunt as I followed Salas scheme (p.53), I guess.
What I have calculated wrong is the input voltage. I thought it would come out 215V but ut is now 240V with the reg attached. I might be running the LEDs a little too hard. Should I adjust the LED-ground - resistor?
I have a 10K test-resistor. At 180V this gives me like 18mA trough it and 18mA shunt as I followed Salas scheme (p.53), I guess.
What I have calculated wrong is the input voltage. I thought it would come out 215V but ut is now 240V with the reg attached. I might be running the LEDs a little too hard. Should I adjust the LED-ground - resistor?
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Just run a bit more current, will be better for the reg and it will sag the trafo a bit. You have quite a sink there, so no problem. Change to a 47 Ohm R1 for about 42mA. The question is if your choke will saturate. How large in VA the TX is and what is its nominal secondary? I don't think you run em hard. What current you derive if you divide the voltage across their resistor to ground by its value?
P.S. You were about to run 2 regs? Then they will sag the secondary for sure. Still 70V is nice for driving faster rise time.
P.S. You were about to run 2 regs? Then they will sag the secondary for sure. Still 70V is nice for driving faster rise time.
Spot on led current I wanted. Also your CCS current looks spot on. Its the leds are really 1.7V it seems. You brobably use the 200V one and your tube rectifier drops 40V. With just a few more mA in the shunt you probably going to make the rectifier duck a bit. Which double diode valve you use? Is it a stiff or limp one for voltage sag?
Ballpark 40-50R will be adequate. It isn't that critical. Just see you don't go over 55c with your final sink, so to have it working reliably for long. The first CLC cap value is going to help you tune your input voltage. Aim for 50V Vdiff in out reg. You will use one shunt for 2 12+12ma bias asking channels?
Holy-macca-smoking-roni.
First impression is very good.
I changed to 6uF first cap and a 47E on R1, got 225V in. Mounted the reg into the preamp and fired up the tubes. Based on the drop over the line-out trafo primary I have 10mA thru one tube and a bit less over the other. Tubes are LED-biased and the LEDs are not matced, nor are the tubes.
Based on "hands-on" measurement and a try with a termometer I guess somewhere between 40-45 C temp.
I`ll post pics and more impressions later.
First impression is very good.
I changed to 6uF first cap and a 47E on R1, got 225V in. Mounted the reg into the preamp and fired up the tubes. Based on the drop over the line-out trafo primary I have 10mA thru one tube and a bit less over the other. Tubes are LED-biased and the LEDs are not matced, nor are the tubes.
Based on "hands-on" measurement and a try with a termometer I guess somewhere between 40-45 C temp.
I`ll post pics and more impressions later.
A few observations:
What are you going to power with your twin regulators? Do you really need 80mA per channel, or is this 80mA going into each regulator? 80mA still is a lot...
Also in order to get 200-300V out you will need 350V max. AFTER the CRC going into the regulator, so your transformer has to put out something like 300V....
What are you going to power with your twin regulators? Do you really need 80mA per channel, or is this 80mA going into each regulator? 80mA still is a lot...
Also in order to get 200-300V out you will need 350V max. AFTER the CRC going into the regulator, so your transformer has to put out something like 300V....
Yes! I need 80ma for one Chanel my pre!
I use 2 tube 6h30 parallel one channel!
what do you think? It is not anything else ???
thank!
First impressions are always indicative. Good it did not alienate you right from the start. Will be nice to know your full news.
