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 ?
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Has anyone found a good technique to keep the insulationpads in place while mounting the powertrannies, without the screws to help?
If you use mica insulators is easier.
Once the power trannies are in place, lift the spring and pull them in with your fingers
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
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you already have 8 nice pairs at hfe490 for the inputs of both boards.
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
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Or maybe Darlington couple some Darlington trannies get hfe of 100000 or more
question How do you mesure them??????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????.
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
