| PanzerLord |
| Any good suggestions for >120V 10-40W BJT drivers (preferebly TO-192 case, low input capacitance)? |
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| sam9 |
| Thats a lot of wats fot to-92. Try Zetex "super e-line" series. maybe something there. There such a thing as a to-92 heatsink - maybe that should be investigated. |
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| PanzerLord |
| ¤%&"%¤/((¤, I meant of course TO-126 case, I`m all messed up, sorry, have been sitting up for 24 hours!:dead: |
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| K-amps |
I love the ones Adcom uses in the smaller amps.
They are Sanken devices 2sa1668 and 2sc4382(?) pair.
Hfe is 60 min to 320 I think . 200vce and 25w.
They sound very nice. |
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| Easyamp |
| Try the 2sd669~2sd49 combo. I always try to use these in the voltage gain stage. |
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| Easyamp |
| oops, I meant 2sd669~2sd649 |
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| sam9 |
| You could also try 2sa1220/2sc2690. Hard to find but try www.matchaknob.com. I think they have them cheap. These seem to be slight upgrades to 2sd669/2sd649. |
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| EchoWars |
| quote: | Originally posted by Easyamp
oops, I meant 2sd669~2sd649 |
The 'A' varients are rated at 160V....
Indeed, these are some of my favorite transistors. Tougher than a lot of TO-220's.
Easyamp...you got a source for these? They seem to be getting more and more of a PITA to find. |
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| Easyamp |
Your right they are hard to find, last time I ordered them I think I got them from Newark electronics but I can't remember.
I just went out and looked at the major suppliers and I didn't see any but I think seal electronics might sell matched pairs.
You might have to go bd139~bd140. They are in my auditory opinion close to the 2sd669~2sb649 pair and they are a lot easier to get.
I've never used
2sa1220/2sc2690 before but they look good on paper and appear to be easy to get.
Good luck |
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| wrenchone |
| Depending on the amount of power dissipated. I use 2SA965/2SC2235 (TO-92L package, 0.9W rating, Toshiba), or 2SA1535A/2SC3944A (Panasonic, TO-220 fullpack). You can get the Toshiba devices from Match-a-Knob, and Digi-Key stocks the Panasonics. |
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| Easyamp |
| quote: | | oops, I meant 2sd669~2sd649 |
Well it's been a while but this post seems have surfaced.
Either everybody was being nice and just thought I meant 2sd669~2sb649 or no one noticed my error, it's not 2sd669~2sd649 it's 2sd669~2sb649. Their is a however a 2sd649 and it's not the comp to the 2sd669.
I haven't been able to find a good source for these gem's other than a few over priced dealers, anybody no of one? |
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| Enzo |
I think they meant the 2SD669 and 2SB649, not 2SD649.
Similar pair is 2SC3117 and 2SA1249.
ANy reason not to use TO220s? I much prefer them. I use the 2SC3298/2SA1306 pair a lot. Used in a number of pro audio products. There are others. |
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| Enzo |
| MCM lists your 669/649 pair at less than a buck each. How cheap you need them? Cheaper than my TO220s. |
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| Jennice |
... or what about 2SC2238 / 2SA968A pair ?
Jennice |
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| ppl |
| the ML#20.5 i belive uses the to220 MJE15030 and MJE15031 as the Vas and CS for it, i use these for driver transistors one of best sounding TO220 8 amp drivers i have found in spite of the 30 MHZ Ft. thanks for the pannasonic tip i have been looking for a set of outs for a headphone amp in the TO126 case and so far the MJE243 sound the most musical in that stage. BTW and sugestions in an ideal ICq for +/- 10 volts and Re=4.7 ohm RL=32-300 ohms. empiricaly i found a minmum of 10 mA and sweet spot is about 25 mA. and 3,5 mA on the 2N5088/5087. what do you guys think? |
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| K-amps |
| quote: | Originally posted by ppl
the ML#20.5 i belive uses the to220 MJE15030 and MJE15031 as the Vas and CS for it, i use these for driver transistors one of best sounding TO220 8 amp drivers i have found in spite of the 30 MHZ Ft. thanks for the pannasonic tip i have been looking for a set of outs for a headphone amp in the TO126 case and so far the MJE243 sound the most musical in that stage. BTW and sugestions in an ideal ICq for +/- 10 volts and Re=4.7 ohm RL=32-300 ohms. empiricaly i found a minmum of 10 mA and sweet spot is about 25 mA. and 3,5 mA on the 2N5088/5087. what do you guys think? |
PPL if you liked the 15030/31, you need to try the 15034/35. They are sweeter and have better bass slam.
:devilr: |
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| ppl |
| The MJE1503XX series seams to be expanding alot. i have some MJE15032 & MJE15033 do you think, these would be more dynamic than the 15030/31 driving a 24 ohm load with +/- 20 volts. im looking at transistors for headphone amp use and i presently use BD139/140. I was thinking the MJE15032 & MJE15033 |
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| K-amps |
My guess is the 32 is closer to the 34 and Better than the 30. The 32 and 34 both have same hfe ranges but the 34 is better for hi-volt apps while the 32 has twice the Ic rating at a lesser vce.
By the way for headphones, I have heard nice things about the 2sd669/2sb649's but have not tested them personally.
Cheers! |
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| ppl |
| one thing i noticed is these 33&34 versions are high voltage type and i suspect Ft would be lower? |
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| K-amps |
If I remember correctly fT of both is 30Mhz and the hfe of both is 50 minimum.
The 15030/31 has inferior values than the 2/3/4/5 |
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| cunningham |
I know that this thread is labled high voltage.
But, I would like to get some feedback on 2N5684/2N5685. Didn't want to make a whole new thread for this. These are something like 80V max, but are quite hefty when it comes to current. This device as I under stand can conduct 50A:att'n: I was wondering what the maximum LINEAR operating current is. I am estimating at or around 9-10A. Does anyone have any data sheets for these devices? (cross referenced to ECG 29 and ECG 30). Beta is around 15-20
Thinking of making a hi power sub amp, Hee Hee.....Thinking class G. :cool: |
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| jcx |
| quote: | Originally posted by ppl
...and so far the MJE243 sound the most musical in that stage. |
would that be "classic" or "new"
http://www.onsemi.com/pub/docs/pcn/13135.pdf
i find it interesting the product change notice assures no parameter changes, how do capacitance and transient/ max thermal parameters not change with die shrink? |
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| Easyamp |
I use mje243/253 as vas and drivers and they seem to work well and for only $.38. The 100v vce rating is very padded. In my vce tester, which is a 340v (originaly 170v) 25ua supply I recently built to find an unknown transistor's vce, I found that transistors are rated for the worst possible vce. I have a 130v 2n3906 while most were 50 or so.
I have 30 something pairs of mje243/253 and the ones tested were all much above there 100v rating more like 160v.
I don't know exactly what this means but I did use a few controll transistors and found most would go 5 - 10% higher then there rated vce so whatever results I get I just subtract 10%.
The tester is an up down 120v 240v transformer rectified, with a 25ua 2n6517 ccs load.
Cheers |
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| AndrewT |
Hi,
can someone tell us what circuit Easyamp used to test his transistors without destroying them?
And how to use/interpret the results? |
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| quasi |
I might be simple, but I use MJE340 /350's almost all the time. Cheap and available almost everywhere.
And they're tough little buggers.
Cheers
Q |
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| john_ellis |
Hi all
The BD139/140's are good for up to 100V but not higher.
The best I've used so far for higher rails are the 160V 2SA968/2SC2268. These were Toshiba's originally, but are now supplied by Magnatec, available from RS. Last time I saw RS description still had Toshiba listed as the manufacturer. Must let them know this is wrong!
Magnatec appear to make "close equivalents". From my knowledge of the fab company I would be surprised if they have not done a good job at providing a good match to the Toshiba's. Have not got a Magnatec data sheet, but frequency response is similar to BD139/140 as measured at 1 MHz (this doesn't say much though).
cheers
John |
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| Eva |
A pair of complementary high voltage drivers that deserve mention are 2SA1837 and 2SC4793.
max. Vce=230V
max. Ic=1A (very linear up to 0.3A)
Ft=70/100Mhz (PNP/NPN)
TO-220 plastic case
Output capacitance=30/20pf (PNP/NPN Vcb=10V F=1Mhz) |
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| ChocoHolic |
...recently started a personal love story with the 2SA1930 & 2SC5171 from Toshiba.
180V/2A/20W
Ft=200MHz
Cob: 16pF(NPN), 26pF(PNP)
Typical gain around 200
Fully isolated TO220
I am not sure if you still find a source...
If yes, then try these devices! |
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| sajti |
2SC2911/2SA1209 from Sanyo, with TO-126 packages, and very very low capacitances. Nice, for VAS, and predrivers too
sajti |
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| destroyer X |
Related the BD139, a very good unit, was used for many years as drivers to Radio Frequency transmitters operating up to 30 Megahertz.
I know about people that have used it to 100 Megahertz FM transmitters too...of course it will loose power in that frequency.
Till 100 Volts it is very good.
regards,
Carlos |
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