After measuring the Transistor ive got from Frans
i got
HFE BC337-40 BC327-40
420...............3x....................................1x
430...............7x....................................2x
440...............8x....................................4x
450..............10x....................................9x
460..............11x..................................15x
470................8x...................................30x !
480................9x...................................27x !
490..............10x..................................10x
500................3x
510...............13x
520...............12x
530................4x
257......................................................1x
289................1x
Measured on duewi DMT7977
The question now is witch to drop where ? 😕
i got
HFE BC337-40 BC327-40
420...............3x....................................1x
430...............7x....................................2x
440...............8x....................................4x
450..............10x....................................9x
460..............11x..................................15x
470................8x...................................30x !
480................9x...................................27x !
490..............10x..................................10x
500................3x
510...............13x
520...............12x
530................4x
257......................................................1x
289................1x
Measured on duewi DMT7977
The question now is witch to drop where ? 😕
Last edited:
If you use mica insulators is easier.
Once the power trannies are in place, lift the spring and pull them in with your fingers
I wonder if its possiple to buy the siliconepad as a sheet, so i can put one piece to cover the whole surface?
Maybe it would be a good idea to start a transistor trading thread.
I have already traded some with Joachim with great result, got a lot of good pairs out of it.🙂
Then look at the assemply guide in post 13 to place the rest. Hesener has a very good explanation there about the ishue.
Kerafol 86/83 in my case
Yes I did cut a strip of a load I got. No problem realy fitting it tiny tiny litle bit of therm grease just to stick them there.
One can first Fit midle transistor on sink set to board, place second transistor hold in place take lot out, clamp repeat for 3, .... once al done Just weld in place altrought the welding part has been frown upon a while ago If you find that you will also find picture of clamping device
In which case line up transistors on board, solder then fit sink and clamp even 4 years old can do that
Clamping device I can sell you for £42 or you can look at picture and buy one for £3.50 😀
Got **** load from Keratherm minimum order qty aplies got 550 X350 mm sheet. do not bother with cut shapes as they charge (rape) for tooling as well
I cut strips of 19 mm so can do TO3P TO247 and TO220 by changing orientation of pack.
By the way before you do all this the TO3 close to sink need to go in and have shorth legs or they touch the sink 😉
Last edited:
Fine by me but Hi Hfe especialy there on inputs is beterer.
I do not have mine so far but I got a stash from Fairchild and Hfe was sky hi on those.
So question: how do you measure them?
Distribution of Hfe values in theory shuld be a bell shape shape on graph paper where midle ground Hfe got more transistors but this if one get full batch
Last edited:
I have now bought and measured about 500 of each On, Fairchild, Diotec, Kec. And i still dont have enough pairs of what you call high hfe, if 490 isnt good enough. Maybe if you buy 5000 of each it will give a fair chance of getting enough so called high hfe😉
question How do you mesure them??????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????.
firs you connect one with hfe490 in one channel, and the mentioned unit in the other, and then compare general funktionality of the two channels😀
Hey I make the jokes here!
No seriously You need to act al grown up and get spelling done proper othervise no one takes you seriously and all you post get dismissed out of hand and even if one is way far ahead in time whit legit questions get ..........😉
Enough of that back to village idiot mode
How do you know first one is 490 then?
If you don' t have litle Atlas unit consider getting one othervise one can calculate delta V against delta I and get Hfe, or sumthink like that (tought was posh to use delta in a sentence) and once one done that there was litle circuit to match transistors a while back.
So stop now othervise we hate you forever😀😀😀
No not realy
No seriously You need to act al grown up and get spelling done proper othervise no one takes you seriously and all you post get dismissed out of hand and even if one is way far ahead in time whit legit questions get ..........😉
Enough of that back to village idiot mode
How do you know first one is 490 then?
If you don' t have litle Atlas unit consider getting one othervise one can calculate delta V against delta I and get Hfe, or sumthink like that (tought was posh to use delta in a sentence) and once one done that there was litle circuit to match transistors a while back.
So stop now othervise we hate you forever😀😀😀
No not realy
This is supposed to be the serious thread, so we better be good boys from now on, and ground the dialog a bit
😀
😀What kind of screws are used to fasten the heatsink to the board? Is it special, or do i just have to be inventious?
😀
😀