Help building this 100 watt ss amp needed

[J M Fahey]

Dear Roly, not disagreeing but pointing to the fact that you certainly got the wrong datasheet, .... or didn´t and you are mixing BD249C with some poor cousin.
The one I´m checking:
http://mht.mht.bme.hu/~beged/elakszim/bd249.pdf
shows that transistor (and its complement, of course) as a beast, WAY over a 2N3055 class transistor:
Type.......2N3055..............BD249C
Case.......plastic 90W........Plastic 125W
.............metal 115W
Current...15 Amp .............25 Amp
VCEO......60V...................100V
VCER......70V....................115V 

The difference in its favor is large enough to allow it to put out 100W .
Not on that poor kit example, of course, but yes on a properly designed (and heatsinked) amp.

[Roly]

Whups    , dunno what happened there, must've keyed the wrong number into the datasheet finder  :duh , thanks for the catch JM.   :tu:

[J M Fahey]

Probably.
What you had found was in the area of TIP41/42 capabilities.
Happens all the time.
Hey!!! a friend was swearing big time today, he bought something on EBay and USPS got the maps mixed up somehow, his pack clearly marked " A ....... rgentina"  got routed to "A ..... ustralia"  , go figure.

OK, it´s way South anyway, isn´t it? 

[Roly]

Half marks for the right hemisphere anyway.   

When George the Lesser arrived in Sydney he gave a speech where he said that he was pleased to be "in Austria".   

No George, Austria is mostly vertical with leaderhosen and yodeling, Australia is mostly horizontal with bikinis and kangaroos.

[J M Fahey]

Just checked and all his friends are making fun at him, hinting that he should go to Australia to pick his parcel personally and that he should thank God it was not sent to A....fghanistan, A....ngola, A....lgeria or A....bidjan.
Oh well.

[Roly]

...or A....ntarctica.


(see it now, before it melts)

[J M Fahey]

Well, Antarctica is fine, one sector is Argentine 
In fact I guess there´s an Australian sector too ... on the opposite side of course, and the Buenos Aires/Auckland commercial plane flies over them.
http://en.wikipedia.org/wiki/Argentine_Antarctica