[AMPS] Blown TL922A... What to do?
Ian White, G3SEK
Ian White, G3SEK" <g3sek@ifwtech.com
Mon, 11 Sep 2000 17:25:33 +0100
measures wrote:
>
>>
>>measures wrote:
>>>The grid protection circuits I am talking about are those that provide no
>>>protection because the transistor that interrupts has too low a current
>>>rating and it shorts during a glitch -- thereby affording no protection.
>>>
>>Failure of that transistor to survive a glitch/arc/parastic/flash-
>>over/whatever is a simple DC design fault that can be cured by a 10K
>>resistor.
>>
>A 10k-ohm resistor can prevent C-E shorts due to excessive collector
>current?
>
>>I don't think that's a good reason to remove grid current protection for
>>normal operation.
>
>Replacing a shorted transistor with a fuse-R is hardly removing
>protection. Shorted transistors afford no protection because they can
>not turn off.
We may be talking about different transistors. Let's start again.
Where in the circuit is the transistor that you say burns out in a
glitch?
Why do you believe that it should be removed, if that also involves
disabling grid current protection in normal operation?
73 from Ian G3SEK Editor, 'The VHF/UHF DX Book'
'In Practice' columnist for RadCom (RSGB)
http://www.ifwtech.com/g3sek
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