Paradise Builders

[GandRalf]

After a new order of BC 337-40 of Conrad, I got two sets of about 50 trannies (337 and 327) within hfe of 450 to 470.

Lucky me!!

May I match the groups even closer then?

-Or is that to much?

[hesener]

Originally Posted by GandRalf

After a new order of BC 337-40 of Conrad, I got two sets of about 50 trannies (337 and 327) within hfe of 450 to 470.

Lucky me!!

May I match the groups even closer then?

-Or is that to much?

thats great! 450-470 is very good, no need to get closer.....

[Joachim Gerhard]

No, that match is really good. Maybe you got the Diotecs. They proved to be well matched several times now.

[GandRalf]

Yes, they are from Diotec.

[Bksabath]

I am starting a new tread on the Swap forums

This should free up the builder tread for trouble shooting and builds tips

In the meantime

I have started to measure the BCXXX-40 I got with goodies bags (Paradise GB)

I tried the Atlas unit again and first test on a sample measure first test Hfe 477 a second test few seconds later measure Hfe 481 is not a big difference considering the 10% tolerance recommended
Measuring with the circuit published by Hesener give me an Hfe of 493 and repeating this give me exactly the same results
I like to test using Hesener circuit as I can see what is happening especially with the problems arising from touching the transistors

Considering that to build this circuit is really inexpensive I am going to stick with it.
BCxxx 40 004 - YouTube

[pdul]

The testing is a very momentary value, not only your fingerheat, but allso the test itself raises the temp. of the transistor, and so with the hfe value. I connect the tester, and let the value find rest before i take note of it

[hesener]

That is a good way of doing it, however time/consuming. You could also take the first stable reading and accept a little bit of variability....

[Bksabath]

Originally Posted by hesener

That is a good way of doing it, however time/consuming. You could also take the first stable reading and accept a little bit of variability....

100 % with this

1000 each how long? how many time you press scroll buton on Atlas how many batteries one uses?

Swap tread started post on how not to waste time linked (post 2)

Paradise BCXXX-40

PS I am not after fame or profits and my R2 is fine and got plenty to build R3 so if you have constructive coments great if not "have a nice day" or the more apropiate Queen English translation for it

[Bksabath]

I am going to populate the R3 boards with 5XX for current sources (done the same for R2 after all) and with the highets matched Hfe I got for the Imputs.
No not today but eventualy
If those oscillate I may need hesener help (Seepost 567) so I may have to volunteer as volunteer N1 but don't think so...

[pdul]

1000 each how long? how many time you press scroll buton on Atlas how many batteries one uses?

I use a rarely mentioned invention, called a powersupply for short PSU, to solve that problem.