And finally, 50 KHz squares, 100V P-P. I am satisfied. Now going to solder the 2'nd channel, the same. I tried to take 2 Hz squares, but my camera is too fast to take a picture. Nice symmetrical output (both in terms of phase and signal level) from an asymmetrical class A 2-stage amplifier. That means, the lower is the level the lower will be distortions. It is very significant because our perception is extremely sensitive to distortions of quiet sounds.
Noise measurements: no cover on the input tube stage, no cover on the entire box, an input transformer have no cover as well. On the nominal level of +35 decibel all hum+noise level is -45 dB. That means, when covered it will be definitely lower than 80 dB, unweighted. Main contributions are 60 Hz and 400 KHz.
Thank you so much 
If I was in the area I'd buy you a beer, or vodka, or whatever. One can learn from this kind of reporting a lot more than a ton of theory. God bless you man.
If I was in the area I'd buy you a beer, or vodka, or whatever. One can learn from this kind of reporting a lot more than a ton of theory. God bless you man.
ikoflexer said:Thank you so much
If I was in the area I'd buy you a beer, or vodka, or whatever. One can learn from this kind of reporting a lot more than a ton of theory. God bless you man.
Thank you my friend! I prefer MoneVie. 😉
What I wanted to show, that High End have nothing to do with black magic, and easily can be designed and engineered.
Get some popcorn, I am going to continue! 😉
Both channels soldered, work identical, 27 dB amplification factor each, 180V P-P max each with no load (well, loaded on 12K feedback resistor).
The mess is covered, now it is a Hollow State IC 😀
Actually, it contains a couple of SMD transistors. Copper leads of resistors soldered to them work as heatsinks.
Actually, it contains a couple of SMD transistors. Copper leads of resistors soldered to them work as heatsinks.
It's time to solder indicators, since drivers work fine.
A poster clip helps again, it is used to hold tiny parts I solder to tube sockets, especially in hard to reach places.
A poster clip helps again, it is used to hold tiny parts I solder to tube sockets, especially in hard to reach places.
Mains input soldered. You may see separate inputs from the same socket for tube compartment (with a flat plug) and for a SS compartment (with own circuit breaker). You may see also common mode chokes there, but I never use any capacitors on the primary side of any gear that has analog power supply. However, it is a different story for switched mode power supplies where they must be used.
