[AMPS] AL-1500, AL-82, AL-1200, QRO???

[2@vc.net (measures)]

>
>Rich wrote :
>
>>Did the amplifier that shorted the 3cx1200A7s have a glitch resistor. ?
>>Who made the amplifier?
>
>Yes. The amplifier is a Henry and has a 25 ohm resistor (+ diode) in the 
>path between the -ve side of the filter capacitor and ground.
>
The glitch R needs to be in the positive HV lead.  
>
>Tom wrote :
>
>>The 3CX1200A7 is probably the most reliable tube out there.
>>Failures are very low. It is also one of the least stable, has high
>>internal capacitance, and is moderately hard to drive. That's the
>>tradeoff.
>
>This may well be true - it seems a solid tube with high grid dissipation 
>capabilities and no issues with a big glass vacuum, but I'm just speaking 
>as I've found. I can't say why the first tube failed - the PA was like that 
>when bought used. 

The 3cx1200A7 has >6x more feedback C than an 8877.  

cheers, Andy

-  Rich..., 805.386.3734, www.vcnet.com/measures.  
end


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