You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.

Reply to thread

Message

25 watt per transistor in the final stage. 1X4 = 100 max 2X4 = 100 max. The 25 per is the result of many a blown transistor and lifespan at different drive levels. Most every builder that has used Toshibas in builds found out the expensive way. One has gone as far as to run them at X watts, check the Hfe, step up to Y watts, then check Hfe and so on. If they found breakdown at Y, they'd go back to X and run it for awhile and check the Hfe. His findings were somewhere between 23-27 watts @ 14VDC provided the longest lifespan with reasonable output so, "25" is an easy number to remember.
Read this a few years ago so I have no way of providing a link though.

[QUOTE="144inBama, post: 805540, member: 58064"] 25 watt per transistor in the final stage. 1X4 = 100 max 2X4 = 100 max. The 25 per is the result of many a blown transistor and lifespan at different drive levels. Most every builder that has used Toshibas in builds found out the expensive way. One has gone as far as to run them at X watts, check the Hfe, step up to Y watts, then check Hfe and so on. If they found breakdown at Y, they'd go back to X and run it for awhile and check the Hfe. His findings were somewhere between 23-27 watts @ 14VDC provided the longest lifespan with reasonable output so, "25" is an easy number to remember. Read this a few years ago so I have no way of providing a link though. [/QUOTE]

Top Bottom