[Amps] I like to think there are no stupid questions

[Mark - N5OT]

Thanks everyone for all the comments.

I figured the idea of whether the two tubes were the same or different 
would enter into the conversation.  I am guessing that the meter on an 
amp with 2 tubes in this case will show the total grid current 
regardless of whether one tube is drawing more than the other.  The seat 
of my pants says that if the two tubes started out new and matched (an 
assumption, I know) and have the same amount of "experience" in this 
single application, they they are likely still relatively balanced.  I 
realize I could be wrong.

Anyway, I have been using it to transmit 1500 watts over the weekend and 
with it tuned like JC N4IS describes (I already knew all that but I'm 
glad to have my opinion backed by a competent authority) the grid meter 
LEDs are never above 70ma.

When an amp trips out, how does one know if it is the tube that flashed 
over, or something else?  I use a number of matching networks and there 
is the occasional arc which shoots the SWR high and the amp trips out. 
If it was a tube, how would I know?

73 - Mark N5OT


On 8/16/2024 12:25 PM, Mark - N5OT wrote:
> I am pretty sure of the answer to this question but I'd hate to find out 
> I am wrong the hard way.
> 
> I am running a pair of pretty flat 3CX800s - Alpha 86.
> 
> Spec on the tube says maximum grid current is 60ma.
> 
> So if my Alpha grid current meter says 70ma, that means it's actually 
> 35ma through each tube, so I'm good?  Am I actually in the okay zone if 
> I see 120ma on the grid current meter?
> 
> Thanks in advance.
> 
> 73 - Mark N5OT
> 
> _______________________________________________
> Amps mailing list
> Amps at contesting.com
> http://lists.contesting.com/mailman/listinfo/amps