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Hello and happy new year for all.
First of all sorry for my poor English.
I am trying to mount a clementine 1626 ECC83 but my OPT is 300-0-300.
With SSR it give 420V and with retifier tube (5AR4, 5Z4P) give me 315V.
Can anyone help me with the appropriate value of the drop resistor?

Taking 25 mA for each 1626 and 10 mA for ECC83 it is a total of 60 mA.
315-250=65V
65V=60 mA x R........R=65/0,060=1083 Ohm.......65 x 0,060 = 3,9 W case of tube rectifier.

420-250=170V
170V=60mA x R.......R=170/0,060=2833 Ohm.....170x0,060=10,2 W case of SSR.

Can anyone tell me if I'm wrong ?

Thanks in advance.














Say me please if it is right , I am a beginner DIY and I have many doubts.

Thanks in advance.
Sorry for my poor English.

Here's my suggestion. You'll need to download Duncan Amp's PSU Designer II to look at the sims. I've attached the stock Clementine Darling PSU and your modded one. Basically I would change the input cap to 2.2uF, the second and third cap to 120uF, and use a 750 ohm, 5W cement resistor where I used a 100 ohm resistor in the stock design. Your ripple will be equivalent to a stock Darling and the power resistor will only dissipate 2.7W. Should work perfectly!

Shannon

Thank you very much for such sage advice.

A question.
What is the reason for lowering the first capacitor?
Why not all capacitors are equal?

greetings

The first capacitor greatly affects the power supply voltage. You can adjust this with the sim and see the effects. A large input cap will be around 400V while a choke input will be much lower than even where we are with 2.2uF. The 2nd and 3rd caps are sized to lower the increased ripple from the smaller first cap. I sized them to match the stock Clementine ripple.

Shannon

O.k.
I understand the sense of small cap.
Following your recomendation 750 Ohms 5w.
Now i am going to work on my new clem amp.

Tanks again.

No prob and good luck! BTW, any tweaks to get near your target voltage are probably best left to adjusting the input cap before the power resistor. So having a handful of values can help tweak it near perfect. Large, 600V coupling-type caps would be ideal: eg, a 0.47uF, a 1uF and a 2.2uF would give you many combinations. They can handle the high ripple due to their low ESR compared to a small electrolytic (which could fail).

Shannon