The bias is slowly crawling up 1mv or so over a minute.
Heat sinks are hot to the touch but you can easily hold your hand on them. Sadly I lack a thermal camera. (really should get one)
I wouldn't be surprised if there is a mistake now. I know my thermistors are too far from the mosfets at minimum. I am attaching pictures. Also I know it's absolutely fugly inside the case. I really should have worked on my wiring skills, but I mostly wanted to see if I could build it.
Heat sinks are hot to the touch but you can easily hold your hand on them. Sadly I lack a thermal camera. (really should get one)
I wouldn't be surprised if there is a mistake now. I know my thermistors are too far from the mosfets at minimum. I am attaching pictures. Also I know it's absolutely fugly inside the case. I really should have worked on my wiring skills, but I mostly wanted to see if I could build it.
Attachments
Would this happen too in a fan cooled setup that wasn't adjusting to temp. but just runs flat out all the time?
To be clear, the effect of the thermal braking provided by the thermistor on the unsensed device is not zero, but it's less that on the primary device.
That said, my sole surviving F5T is on an open bench with fans blown towards a slightly inadequate heatsink. It does take a long time to warm up, the bias adjustment is more tricky, but I have no difference between the devices because I do not use the same method of compensating for temperature as the F5T schematic. I guess if I did, I would see a difference at least between the two devices. But the fan does force a more or less constant temperature on the heatsink, thus it might not actually exhibit a constantly rising difference.
That said, my sole surviving F5T is on an open bench with fans blown towards a slightly inadequate heatsink. It does take a long time to warm up, the bias adjustment is more tricky, but I have no difference between the devices because I do not use the same method of compensating for temperature as the F5T schematic. I guess if I did, I would see a difference at least between the two devices. But the fan does force a more or less constant temperature on the heatsink, thus it might not actually exhibit a constantly rising difference.
Hello,
newbie woobie question.
I'm doing rough planning of future F5T v3 monoblocks - target is +-45V powersupply for 100 class A watts per monoblock.
I would not use diodes, but would use more output pairs to increase current delivery. It would be cascoded front end of course with these voltages. Chassis and heatsinking are not a problem.
Could I use 6 output pairs with one input jfet pair, or is that already too much for only two little Toshiba creatures? Stability and bandwith with 6 pairs? Mayba not more pairs but a bit lower source resistors? How many pairs should one drive before using parallel pairs of input jfets...
Sorry if I missed exact explanation somewhere...
Thanks!
newbie woobie question.
I'm doing rough planning of future F5T v3 monoblocks - target is +-45V powersupply for 100 class A watts per monoblock.
I would not use diodes, but would use more output pairs to increase current delivery. It would be cascoded front end of course with these voltages. Chassis and heatsinking are not a problem.
Could I use 6 output pairs with one input jfet pair, or is that already too much for only two little Toshiba creatures? Stability and bandwith with 6 pairs? Mayba not more pairs but a bit lower source resistors? How many pairs should one drive before using parallel pairs of input jfets...
Sorry if I missed exact explanation somewhere...
Thanks!
