Glad that I have tons of pulled and otherwise useless ECC82's from old (1950ies) TV's, made by Valvo, Telefunken, Siemens etc.
Best regards!
Best regards!
Hi Evan,
This is quite a nice build you have there! Did you get a chance to do any listening?
Thanks
Do
This is quite a nice build you have there! Did you get a chance to do any listening?
Thanks
Do
Yes, exactly! ECC 82 was a very versatile, very universal tube in German TV sets in that era. I've slaughtered dozens ot old TV's in my youth.
Best regards!
Best regards!
Here's an update on the project! I have installed the first amp module on the heatsink. PSU is installed but not yet tested. I've ordered my transformer from Toroidy, a 1Kva with four secondaries for OPS, four secondaries for IPS and two secondaries for the filament supply if I decide to use it. It will be regulated using Jeff's filament supply.
I wish I could be faster but I'm working on two different projects.
VZaudio Amplificateur NS Modular
Ciao!
Do
I wish I could be faster but I'm working on two different projects.
VZaudio Amplificateur NS Modular
Ciao!
Do
Here's an update on the project! I have installed the first amp module on the heatsink. PSU is installed but not yet tested. I've ordered my transformer from Toroidy, a 1Kva with four secondaries for OPS, four secondaries for IPS and two secondaries for the filament supply if I decide to use it. It will be regulated using Jeff's filament supply.
I wish I could be faster but I'm working on two different projects.
VZaudio Amplificateur NS Modular
Ciao!
Do
I wish I could be faster but I'm working on two different projects.
VZaudio Amplificateur NS Modular
Ciao!
Do
It's looking good so far! The filament supply needs it's own transformer though. The control board will start it up before the main transformer so the tube is warm before the amp is started.
Generally Local decoupling reduces ringing and oscillation? Isnt it?
Im currently using 100uF/100V cap with 100nF in parallel and closer to the pins.
If 22uF is sufficient then it would be great. I use to think using a 100uF is not sufficient and it has to be large like 470uF for better energy proximity for the OP transistor to get the energy instantaneously. I agree its a small cap and can charge quickly hence not required to have larger value but I feel having a larger cap will actually help with multiple 100nF and then 10nF cap to stop the oscillation and ringing in the OPS. Please tell me if there is anything else to be considered? Finally 22uF with 100nF in parallel?
Don't put 22uF and low ESR 100nF in parallel.
They need some resistance between them to damp any ring when fed with a step change current.
Put the 100nF (or other sizes) right on the current consumer.
Put the electrolytic nearby, but on longer traces/leads.
If you want you can use a three stage decoupling.
Tomchr gives details on his website.
They need some resistance between them to damp any ring when fed with a step change current.
Put the 100nF (or other sizes) right on the current consumer.
Put the electrolytic nearby, but on longer traces/leads.
If you want you can use a three stage decoupling.
Tomchr gives details on his website.
I haven't studied these effects myself but I can see possible issues with large amounts of local decoupling in a high current circuit. Adding a capacitor near a device can provide extra instantaneous current but there can be issues when the capacitor is recharged. Electricity like anything else has mass. If it is stopped it wants to remain stopped. If it's in motion it wants to remain in motion.
Think of water hammer in a pipe, you shut a tap off quickly the pipes jump around. Now add some air to the pipe (more capacitance). When the tap is closed quickly water continues to move and compress the air after the tap is closed due to the weight of the water causing a huge amount of pressure to be generated and the pipes really jump around or burst. Once the water stops it will flow backwards due to the extreme pressure at the tap. Again due to the weight of the water it will continue to flow until pressure at the tap is considerably lower than the main line, then flow towards the tap again repeating the cycle (oscillation) until friction in the pipe (resistance) stabilizes things.
If you can calculate the size of the capacitor in the circuit correctly at a given frequency you can tune out the oscillation, but this is audio so we are never operating at a fixed frequency.
For all the car buffs out there (EvanC) this is the key to making an intake manifold or exhaust headers work. The air in an intake runner is oscillating. We tune the runner size so the oscillations are at their peak and shut the intake valve when the pressure is at it's maximum supercharging the fuel air charge in the cylinder. We tune the exhaust tubing the same way and shut the exhaust valve when the pressure is at its lowest point vacuuming the burnt fuel air mix out. If the components are properly selected this will all be happening at the same rpm (powerband).
Think of water hammer in a pipe, you shut a tap off quickly the pipes jump around. Now add some air to the pipe (more capacitance). When the tap is closed quickly water continues to move and compress the air after the tap is closed due to the weight of the water causing a huge amount of pressure to be generated and the pipes really jump around or burst. Once the water stops it will flow backwards due to the extreme pressure at the tap. Again due to the weight of the water it will continue to flow until pressure at the tap is considerably lower than the main line, then flow towards the tap again repeating the cycle (oscillation) until friction in the pipe (resistance) stabilizes things.
If you can calculate the size of the capacitor in the circuit correctly at a given frequency you can tune out the oscillation, but this is audio so we are never operating at a fixed frequency.
For all the car buffs out there (EvanC) this is the key to making an intake manifold or exhaust headers work. The air in an intake runner is oscillating. We tune the runner size so the oscillations are at their peak and shut the intake valve when the pressure is at it's maximum supercharging the fuel air charge in the cylinder. We tune the exhaust tubing the same way and shut the exhaust valve when the pressure is at its lowest point vacuuming the burnt fuel air mix out. If the components are properly selected this will all be happening at the same rpm (powerband).
I don't know how teachers can do their job these days. I don't deal well with the short attention span of kids these days and here in Canada teachers aren't allowed to do anything about this.
Got the missing temperature sensor last Friday and got the address. I was able to load the software today in the controller and everything seems to be working properly. Relay timing is good and they all seem to be clicking properly. Still need to install the fuses and test the supplies but it is coming along pretty good.
Do
Do
Sorry, your electricity analogy with hydraulics is all wrong.
Electricity has no mass to stop and go. Electric oscillations have nothing to do with mass or inertia.
Electron - Wikipedia "The invariant mass of an electron is approximately9.109×10−31 kilograms, or5.489×10−4 atomic mass units. " If you can give a better explanation in simple terms for someone new to the hobby feel free to pipe up, otherwise quit trolling.
I think ringing and overshoot occurs due to the inductive properties of the conductor, rather than electron mass.
Best regards!
Best regards!
