F5 bias problems.
Hello everyone, I don't know if this is the place to ask for help.
I built an f5 - v3 diyaudio board and have a problem adjusting the bias on one of the channels.
The right channel is stable 0.60 v at R7 / R8, the left channel oscillates between 0.57 v and 0.65 v approximately at R7 / R8, rises slowly and then slowly decreases, the offset is 0.
I don't know if this is normal and I don't know how to solve it, so I ask for help.
The amplifier works but I'm afraid of an accident. I don't understand anything electronic, I follow the assembly instructions and make the measurements, but I don't know anymore, so I ask for help to those who know.
Thanks.
Subdias.
Hello everyone, I don't know if this is the place to ask for help.
I built an f5 - v3 diyaudio board and have a problem adjusting the bias on one of the channels.
The right channel is stable 0.60 v at R7 / R8, the left channel oscillates between 0.57 v and 0.65 v approximately at R7 / R8, rises slowly and then slowly decreases, the offset is 0.
I don't know if this is normal and I don't know how to solve it, so I ask for help.
The amplifier works but I'm afraid of an accident. I don't understand anything electronic, I follow the assembly instructions and make the measurements, but I don't know anymore, so I ask for help to those who know.
Thanks.
Subdias.
To change my f5 enclosure i removed f5 pcb and re install into new one. Then i made a mistake wrong polarity connection V+ power source to V- and V- power source to V+. Even i correct it after, now i saw smoke on ground cable connection on pcb and R2 resistor heat like hell. Pcb version v3.0. Any guess about which componenets get damaged?
Given the slow nature of this, it is likely the thermistor circuit.
I don't think it will do any damage in the meantime.....
For 3W, either Panasonic metal oxide, or Vishay CPF.
For 0.5W Vishay CMF 55, or maybe Caddock radial.
Also you could make some rough calculation and look after a heatsink with C/W number that is small enough for your requirements. E.g. if you tolerate 60 C on heatsink with ambient 25 C then you have 35 C temp raise to "play with". If you put let us say 80W pr. side out in heat then you should look for a 35/80 = 0.4 C/W heatsink. Then to be safe maybe look for 0.2 - 0.3 C/W heatsink (assuming 80W dissipation pr side.....have not checked).
Flamethrower1, did the 3U come with any holes drilled or did you need to drill and tap?
Hi folks, I am sure a lot of you will be able to answer my question: if I compare the original design of F5 with the v3 schematic, i see a few changes (obviously) - are these changes something essential that will change the sound of the amp, or are just because of the turbo compatibility? I don't understand these schematics, so it's not obvious for me. Thanx for the clarifications!
