temp critical, but in case of 2SB206, power derating with each deg. is thing to take care of
from memory, 80W max ......
if you stumble on datasheet having more than few basic numbers, pin it here
from memory, 80W max ......
if you stumble on datasheet having more than few basic numbers, pin it here
Type Designator: 2SB206
Material of Transistor: Ge
Polarity: PNP
Maximum Collector Power Dissipation (Pc): 80 W
Maximum Collector-Base Voltage |Vcb|: 80 V
Maximum Collector-Emitter Voltage |Vce|: 60 V
Maximum Emitter-Base Voltage |Veb|: 40 V
Maximum Collector Current |Ic max|: 30 A
Max. Operating Junction Temperature (Tj): 85 °C
Transition Frequency (ft): 0.1 MHz
Forward Current Transfer Ratio (hFE), MIN: 50
Noise Figure, dB: -
Package: TO3
Material of Transistor: Ge
Polarity: PNP
Maximum Collector Power Dissipation (Pc): 80 W
Maximum Collector-Base Voltage |Vcb|: 80 V
Maximum Collector-Emitter Voltage |Vce|: 60 V
Maximum Emitter-Base Voltage |Veb|: 40 V
Maximum Collector Current |Ic max|: 30 A
Max. Operating Junction Temperature (Tj): 85 °C
Transition Frequency (ft): 0.1 MHz
Forward Current Transfer Ratio (hFE), MIN: 50
Noise Figure, dB: -
Package: TO3
yes
what we need more is junction-case thermal
and power derating per each junction C
in these params, 2N1099 and 1T813 are safe enough with Iq 1A, well heatsinked
of course, THD Spectra is not saying everything and nothing can replace actual listening evaluation
what I can say ( maybe I did already) there is some canny holographic quality in Old SOul sound, which I'm finding as most prominent characteristic
everything else is nothing to write home about, but take care that I'm speaking from position of bloody high references, so I'm hardly ever excited with sound itself of all gadgets I made
simply - it must sing properly ....... and I'm only refreshing my evaluation tool when stumbling on some factory made amplification, most often finding myself asking - WTF is this - and people are actually taking money for this Drek!?!?
what we need more is junction-case thermal
and power derating per each junction C
in these params, 2N1099 and 1T813 are safe enough with Iq 1A, well heatsinked
of course, THD Spectra is not saying everything and nothing can replace actual listening evaluation
what I can say ( maybe I did already) there is some canny holographic quality in Old SOul sound, which I'm finding as most prominent characteristic
everything else is nothing to write home about, but take care that I'm speaking from position of bloody high references, so I'm hardly ever excited with sound itself of all gadgets I made
simply - it must sing properly ....... and I'm only refreshing my evaluation tool when stumbling on some factory made amplification, most often finding myself asking - WTF is this - and people are actually taking money for this Drek!?!?
"simply - it must sing properly ....... and I'm only refreshing my evaluation tool when stumbling on some factory made amplification, most often finding myself asking - WTF is this - and people are actually taking money for this Drek!?!?"
I guessing there are a large number of people who don't actually listen to the music.
Their components are some sort of status symbol for impressing others (who also don't listen to the music)
I am so glad I met Nelson some 40 years ago and asked if he would do a crossover and amps for my AMT Heils. We listened to his KEFs ( I think with Heil tweeters but can't be sure of that) before he helped me with my system. No looking back. I have met so many people here on this forum who understand its about the feeling that you get when listening.The right components take you there. I may not have saved money building but at least I understand (somewhat) the circuits and absolutely enjoy what I hear.
Enough rambling
Omni ZM - thanks for not adding to the Drek !!!
Hopefully you, Nelson and Mike R will get together at BA some day for a true Super Session
I guessing there are a large number of people who don't actually listen to the music.
Their components are some sort of status symbol for impressing others (who also don't listen to the music)
I am so glad I met Nelson some 40 years ago and asked if he would do a crossover and amps for my AMT Heils. We listened to his KEFs ( I think with Heil tweeters but can't be sure of that) before he helped me with my system. No looking back. I have met so many people here on this forum who understand its about the feeling that you get when listening.The right components take you there. I may not have saved money building but at least I understand (somewhat) the circuits and absolutely enjoy what I hear.
Enough rambling
Omni ZM - thanks for not adding to the Drek !!!
Hopefully you, Nelson and Mike R will get together at BA some day for a true Super Session
Hopefully
together with my Uncle Bubba Bob ...... scene of 4 Old Bulls, watching bunch of young Bulls chasing ...... The Rainbow, or something like that
Weirdness ..... 🙂
Did mount 1T813 today, in place of 2N1099
fired it up, it set itself exactly at same Iq (as previously 2N1099) , did just minor tweak of output offset
same situation for both channels - everything perfect in static state
then connected old crummy Sigene to input, scope to out, no load, just to check does modulation reaching output
first channel OK
second channel - started , and somewhere at half ( of max) thingie just went South - speaker DC protection dissengaged relays, got 48V across 0R11 resistor group ( where I need to see 110mV)
powered it off, logical check - dead mosfet, dead Ge, two 0R22 resistors dead ( there is a reason why there are 2 or 3W jobbies)
was it 1T813 Dud ? most likely ...... and now I'm thinking what and how to test them if I decide to get them in quantity
it seems test with actual load, fastest way of Ge tossed in 1L container of demi water is easiest way to do it
anyway - replaced what's Dodo, checked rest of circuit and fired it up again
this time everything went good, so did tried both channels with load, up to clipping
Did mount 1T813 today, in place of 2N1099
fired it up, it set itself exactly at same Iq (as previously 2N1099) , did just minor tweak of output offset
same situation for both channels - everything perfect in static state
then connected old crummy Sigene to input, scope to out, no load, just to check does modulation reaching output
first channel OK
second channel - started , and somewhere at half ( of max) thingie just went South - speaker DC protection dissengaged relays, got 48V across 0R11 resistor group ( where I need to see 110mV)
powered it off, logical check - dead mosfet, dead Ge, two 0R22 resistors dead ( there is a reason why there are 2 or 3W jobbies)
was it 1T813 Dud ? most likely ...... and now I'm thinking what and how to test them if I decide to get them in quantity
it seems test with actual load, fastest way of Ge tossed in 1L container of demi water is easiest way to do it
anyway - replaced what's Dodo, checked rest of circuit and fired it up again
this time everything went good, so did tried both channels with load, up to clipping
Attachments
Hopefully
together with my Uncle Bubba Bob ...... scene of 4 Old Bulls, watching bunch of young Bulls chasing ...... The Rainbow, or something like that
My dream 😀😀😀😀😀😀
now even more weirdness
checked trice entire setup, done each step at least twice, when seeing how THD numbers are weird
8R load
checked trice entire setup, done each step at least twice, when seeing how THD numbers are weird
8R load
Attachments
We're in a drek free zone here. 🙂
It's nice to read that something readily available like the 2SA1943 can be used.
And an insane summer amp sounds like a wonderful project.
Cheers,
Dennis
It's nice to read that something readily available like the 2SA1943 can be used.
And an insane summer amp sounds like a wonderful project.
Cheers,
Dennis
Tomorrow will THD test other channel, for reference
Still can't wrap my head around exact mechanismus happening here ....... THD Spectra is weird, at least for my untrained eye
will give it some listening and - if I'm able to draw some conclusions in relatively short time, will proceed with 2SA1943 in place of 1T813
from prototyping, I know that iteration is also extremely interesting ...... and certainly most easy one, taking in account acquisition of parts
Still can't wrap my head around exact mechanismus happening here ....... THD Spectra is weird, at least for my untrained eye
will give it some listening and - if I'm able to draw some conclusions in relatively short time, will proceed with 2SA1943 in place of 1T813
from prototyping, I know that iteration is also extremely interesting ...... and certainly most easy one, taking in account acquisition of parts
I was digging around the depths of the Internet last night and found this one for the 2SB205 which is the same family / same case...
It seems feasible to carry the same numbers over for the 2SB206 potentially? It states a Junction to Case derating value of 1.3 c/w. The New Jersey SC datasheet from before states 1.3 of an undefined derating from 25c. Fair to work towards an assumption of Junction to Case derating of 1.3 c/w from 25c? Or am I talking complete gibberish?
Thanks ZM, I'm learning new things every day hanging around in your threads, worst case scenario I'm wrong but at least engaging my brain a little while on holiday
2N277 possible?
2N277
Datasheet, Equivalent, Cross Reference Search. Transistor Catalog
2N277 Datasheet, Equivalent, Cross Reference Search
Type Designator: 2N277
Material of Transistor: Ge
Polarity: PNP
Maximum Collector Power Dissipation (Pc): 170 W
Maximum Collector-Base Voltage |Vcb|: 40 V
Maximum Collector-Emitter Voltage |Vce|: 25 V
Maximum Emitter-Base Voltage |Veb|: 20 V
Maximum Collector Current |Ic max|: 15 A
Max. Operating Junction Temperature (Tj): 95 °C
Transition Frequency (ft): 0.2 MHz
Forward Current Transfer Ratio (hFE), MIN: 35
Noise Figure, dB: -
Package: TO36
2N277 Transistor Equivalent Substitute - Cross-Reference Search
2N277
Datasheet, Equivalent, Cross Reference Search. Transistor Catalog
2N277 Datasheet, Equivalent, Cross Reference Search
Type Designator: 2N277
Material of Transistor: Ge
Polarity: PNP
Maximum Collector Power Dissipation (Pc): 170 W
Maximum Collector-Base Voltage |Vcb|: 40 V
Maximum Collector-Emitter Voltage |Vce|: 25 V
Maximum Emitter-Base Voltage |Veb|: 20 V
Maximum Collector Current |Ic max|: 15 A
Max. Operating Junction Temperature (Tj): 95 °C
Transition Frequency (ft): 0.2 MHz
Forward Current Transfer Ratio (hFE), MIN: 35
Noise Figure, dB: -
Package: TO36
2N277 Transistor Equivalent Substitute - Cross-Reference Search