Hi Jean-paul，
“Huitie”In Chinese pinyin, meaning "you answer my published articles." 😀 😀
very nicely laid out , can't wait to see the fet's populated.
what size heatsink are you going to use? what c/w rating? are you going to force cool with fan?
what size heatsink are you going to use? what c/w rating? are you going to force cool with fan?
Process is as follows:
1)Voltage is: DC80V,+-44V
2)Midpoint voltage:0V
3)Because of heat sink is not big enough, a pair of tube current:450mA
4)Noise floor is perfect, look at the oscilloscope.
1)Voltage is: DC80V,+-44V
2)Midpoint voltage:0V
3)Because of heat sink is not big enough, a pair of tube current:450mA
4)Noise floor is perfect, look at the oscilloscope.
i don't understand?
Is your bias per device 450mA ?
/sorry i see now. 450mA per voltage rail , but you have one device per rail so it is slightly less if you don't take other losses into account.
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Hi
thats mean you are so kind,
pls send me pm
how much shipping cost to jakarta indonesia
(if you can pls use registered post)
is this include the pre board?
i want ask u
how big the heatsink for your PCB
in the Krell ksa50 mk2 PCB some friend use
Conrad Heatsink lenght 30cm height 15 cm
but he run bias 1,5A if more than that (1,9A) was like toaster
so he set up back the bias to 1,5A
thats mean you are so kind,
pls send me pm
how much shipping cost to jakarta indonesia
(if you can pls use registered post)
is this include the pre board?
i want ask u
how big the heatsink for your PCB
in the Krell ksa50 mk2 PCB some friend use
Conrad Heatsink lenght 30cm height 15 cm
but he run bias 1,5A if more than that (1,9A) was like toaster
so he set up back the bias to 1,5A
Hi
1.Yes, send EMS to you?
2.Now that the PCB, not including the preamplifier, Preamplifier PCB10 days after the make.
3.Heat sink size is based on your use of the quiescent current to decide.
1. i think ems is ok, they are not weight enough
2. ok then for the pre amp
3. for your design how much current need to produce 50w output
btw gxcnabin can you give us list of BOM (Build of material)
to look the small character on the schematic is to tired for the old eyes
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For 50W class A for 8 ohm load using 2 pairs you will need 883ma PER device.
That calculates to 1.77A per voltage rail idling.
for 0.47ohm resistor like on this pc board that calculates to 415mV voltage drop over resistor.
your heatsink will have to be around 0.2 C/W per channel. BIG!!!
(hope i did those calculations correct?)
gxcabin , how much for posting 2 boards to South africa?
I am amped about this design, hehe
That calculates to 1.77A per voltage rail idling.
for 0.47ohm resistor like on this pc board that calculates to 415mV voltage drop over resistor.
your heatsink will have to be around 0.2 C/W per channel. BIG!!!
(hope i did those calculations correct?)
gxcabin , how much for posting 2 boards to South africa?
I am amped about this design, hehe
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