High Vceo audio transistors - Page 2 - UK Vintage Radio Repair and Restoration Discussion Forum

Radio Wrangler · 28th Feb 2019, 12:05 pm

I think the Tek curve tracer goes high enough in voltage.

I wouldn't worry about audio/non-audio transistors. Go for 500v Vce rating and check the Ft isn't much different. A 100v line driver isn't going to be esoteric hifi and a little distortion is unlikely to be noticed. Unreliability will be noticed, and a slow transistor risks loop instability while a superfast RF transistor risks localised RF instability if there aren't stopper resistors in the right places.

THe problem for using reasonably fast 500v switching bipolars is that complements may be hard to find.

Going to complementary Mosfets will lead to almost a full redesign.

David

28th Feb 2019, 12:05 pm	#21
Radio Wrangler Moderator Join Date: Mar 2012 Location: Fife, Scotland, UK. Posts: 22,899	Re: High Vceo audio transistors I think the Tek curve tracer goes high enough in voltage. I wouldn't worry about audio/non-audio transistors. Go for 500v Vce rating and check the Ft isn't much different. A 100v line driver isn't going to be esoteric hifi and a little distortion is unlikely to be noticed. Unreliability will be noticed, and a slow transistor risks loop instability while a superfast RF transistor risks localised RF instability if there aren't stopper resistors in the right places. THe problem for using reasonably fast 500v switching bipolars is that complements may be hard to find. Going to complementary Mosfets will lead to almost a full redesign. David __________________ Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done