Hi,
I want to build an amp using Sanken 2SA2922/2SA1216 in the end stage. The current amplifier will have 3 stages.
Does anybody know which driver transistors can be used and are easy to get (maybe from Schuro in Germany). I was first thinking of ON semiconductor MJE340/350 for the 1st stage, ON semiconductor MJE15028/15029 for the second stage and Sanken 2SA2922/2SA1216 in the last stage.
I can imagine the Japanese may have better transistors than ON semiconductor.
Any good suggenstions?
Kees
I want to build an amp using Sanken 2SA2922/2SA1216 in the end stage. The current amplifier will have 3 stages.
Does anybody know which driver transistors can be used and are easy to get (maybe from Schuro in Germany). I was first thinking of ON semiconductor MJE340/350 for the 1st stage, ON semiconductor MJE15028/15029 for the second stage and Sanken 2SA2922/2SA1216 in the last stage.
I can imagine the Japanese may have better transistors than ON semiconductor.
Any good suggenstions?
Kees
The MJE150xx series do have pretty low gain at low current. If you measure them with a multimeter, you get gains on the order of 20. Gains gets better at intermediate levels before it drops off again at several A. I wonder if this causes a problem when the transistor just starts to conduct.
Also, these devices are not exactly fast, with an f_T of 30 MHz. The Sankens you want to use have about 50 MHz.
Sanyo makes TO-126 video transistors, the older series having 150 MHz, the newer about 400 MHz. Current gain is very flat from 0-1 A. Should make nice VAS stages, too. The part numbers are in the thread "new law".
Eric
Also, these devices are not exactly fast, with an f_T of 30 MHz. The Sankens you want to use have about 50 MHz.
Sanyo makes TO-126 video transistors, the older series having 150 MHz, the newer about 400 MHz. Current gain is very flat from 0-1 A. Should make nice VAS stages, too. The part numbers are in the thread "new law".
Eric
MJE340/350 as input transistor seems a little bit not 
. I would use some low noise small signal transistor like BC5xx series. If the power supply voltage is high, use a cascode.
Gain Hfe >300
fT >100 Mhz
Ic 300 mA
Uce 20-50% more than you have as power supply voltage.
BC546/47/48/49/50 NPN
BC556/57/58/59/60 PNP
Or the excellent and cheap BC847BS/BC857BS, see picture below
http://home5.swipnet.se/~w-50719/hifi/qsxm2/layout_qsxm2.html#Anchor-47857
. I would use some low noise small signal transistor like BC5xx series. If the power supply voltage is high, use a cascode.Gain Hfe >300
fT >100 Mhz
Ic 300 mA
Uce 20-50% more than you have as power supply voltage.
BC546/47/48/49/50 NPN
BC556/57/58/59/60 PNP
Or the excellent and cheap BC847BS/BC857BS, see picture below
http://home5.swipnet.se/~w-50719/hifi/qsxm2/layout_qsxm2.html#Anchor-47857
The 340, 350 are not as good as the 2sa1837, 2sc4793 which have a flatter beta for drivers. For the front end try 2sa1016, 2sc2362.
Thanks for the suggestions.
Do you have a good source for these 2SA... and 2SC... transistors?
I live in the Netherlands. I believe Schuro in Germany might have them but they don't answer to emails or faxes and are hard to get hold on. I want to place 1 or 2 orders for all components in order to avoid minimum order and freight charges.
However I noticed that Schuro is about to introduce their Millenium XP Amp that uses the Sanken transistors, see
http://www.schuro.de/preisl-mill-xp.htm
Let's see what will be the drivers in that design.
Thanks for the help!
Do you have a good source for these 2SA... and 2SC... transistors?
I live in the Netherlands. I believe Schuro in Germany might have them but they don't answer to emails or faxes and are hard to get hold on. I want to place 1 or 2 orders for all components in order to avoid minimum order and freight charges.
However I noticed that Schuro is about to introduce their Millenium XP Amp that uses the Sanken transistors, see
http://www.schuro.de/preisl-mill-xp.htm
Let's see what will be the drivers in that design.
Thanks for the help!
Kees,
try www.reichelt.de. They have all kinds of Japanese parts. Problem with them: they won't tell you the gain grade...
Eric
try www.reichelt.de. They have all kinds of Japanese parts. Problem with them: they won't tell you the gain grade...
Eric
data sheets for 2SA968 and 2SC2238
Hi,
I found out that transistors 2SA968 and 2SC2238 are good available.
However I cannot find a data sheet. I believe these are from Toshiba but there is nothing on their web site.
Does anybody have a PDF ?
Hi,
I found out that transistors 2SA968 and 2SC2238 are good available.
However I cannot find a data sheet. I believe these are from Toshiba but there is nothing on their web site.
Does anybody have a PDF ?
Drivers
Hi,
Toshiba make som great new drivers to replace 968/2238.
They have ft= 70 Mhz (less than the old ones) but are reated to 230 V
I have PDF's of all types
2sa1837 and 2sc4793
\Jens
Hi,
Toshiba make som great new drivers to replace 968/2238.
They have ft= 70 Mhz (less than the old ones) but are reated to 230 V
I have PDF's of all types
2sa1837 and 2sc4793
\Jens
- Status
- Not open for further replies.