Last edited:
Thanks Zung so I took a similar approach as yours, so far I measured the Toshiba 2SA1986-R PNPs and got Hfe and Vbe curves at an average 601mA @ 36VE which is the Max Voltage my little Curve tracer can handle, and; out of a lot of 60 I got 2 groups of 11 matched to 3.91% Hfe and 0.4% Vbe between them and 5% Hfe and 0.6% Vbe across them. I think this would be good enough, not that I have more transistors anyway...
I will do the NPNs next...
I will do the NPNs next...
Expect a lower yield matching P & N for Hfe.
Getting opposite sex to get along is more difficult. 🙂
Getting opposite sex to get along is more difficult. 🙂
Attachments
Last edited:
I think one is shown, but can't remember how far back
thread was sorta busy, and I'm easy to confuse
thread was sorta busy, and I'm easy to confuse
Mine is about half way done, but progress is slow due to other commitments at the moment - no hurry though. Slow and steady wins the race here.
I'm getting closer, waiting on the transformer from Airlink...ordered start of April.
I hope it is going to beat my KSA50 🙂
I hope it is going to beat my KSA50 🙂
Yeap, as predicted I measured the Toshiba 2SC5358-O NPNs and got same curves at same average 601mA and again out of a lot of 60 I got 2 groups of 11 matched to a much higher 7.85% and 11.78% Hfe and similar 0.4% Vbe between them and 11.78% Hfe and 0.5% Vbe across them.
Definitely Hfe difference between PNP and NPN is big 102 vs 76 average but Vce is practically the same.
Attachments
Maybe post some photos even if it’s just the parts you purchased, it will keep you focused, and I will also keep nagging you.
Hahaha
No. Every time i get close to ordering parts, i end up getting a new toy for the baby
How old is the baby now?
At Threshold we measured output transistors for current gain, choosing the higher ones for better performance. Betas of 80+ were chosen, and we found other uses for lower gain ones.
Thanks Mr. Pass, yes I basically choose the ones with highest Beta on the lot and then started removing the ones with the lowest Beta or that were very out of the bunch until I came up with the groups, unfortunately the NPNs I got are in the lowest side of their Range for the O classification.
But if I build another set of Output Boards I will definitely choose BJTs with higher Beta.
Last edited:
Shes 5 months and a complete firecracker. I don’t think shes gonna have any issues speaking her mind when the time comes haha
Trying to finish the Boards and mount them on the heathsinks today, while choosing the washer I found something interesting, see the picture so I’m debating between 16mm and 20mm, what do you think?
They were all tightened up to 9nm.
Adding a second picture, in this one you can see the damage that the pads took with the different washers, clearly the biggest the washer the least the damage.
They were all tightened up to 9nm.
Adding a second picture, in this one you can see the damage that the pads took with the different washers, clearly the biggest the washer the least the damage.
Last edited:
