BD829-30 as drivers and VAS

[sakis]

i come accros some bd 829-30 transistors that they look very nice quality made by philips .... matched pairs actually

( been very lucky these days went to a shop to get bc 546 so i got about 20 that where made by siemens and printed on them was the simens logo BC546-B and down under a number 351 ..... well allof them presented exaclty hfe of 351 !!!!! odd !!!! )

any way ....do you think that worth trying them in P3A as drivers and VAS ?????

[mjf]

hello.
a bc 546b measured with an ordinary digitalmultimeter (hfe test) shows usually a hfe value around 250 or so...............by accident?
the bd 829/830 are driver transistors like bd139/bd140..........i think there will be no great difference -
but try it out,why not?
greetings................

[sakis]

in my box of BC546....i can find you dut from a hfe100 to hfe 400.......

i was never matching my ltp pairs( i thought that it was enough to have same brand and model .... but once made a post here given the advice and eversince i realized that it makes a hell of a diference

regards sakis

[mjf]

hello.
i asorted my bc546 box: hfe around 150 = bc546a,
hfe r.a. 250 bc546b ,and hfe > 350 is c -type...........and lower than 100 is for the garbage container.
a ltp circuit uses on principle two equal transistors.........
but if they are not very similar you can use bigger feedback "to make them equal on their properties" ..............
greetings.........