[Elecraft] [Fwd: Re: [KPA500] IO Board Schematic]

[Eric Swartz - WA6HHQ, Elecraft]

Ah, but Wayne and I have veto power.. both have to agree.  :-)
e

-------- Original Message --------
Subject: 	Re: [KPA500] IO Board Schematic
Date: 	Tue, 24 Nov 2009 17:35:05 -0800
From: 	Lyle Johnson <kk7p at wavecable.com>
To: 	Eric Swartz - WA6HHQ, Elecraft <eric at elecraft.com>
CC: 	Robert Friess <rfriess at usa.net>, Jack Brindle 
<jackbrindle at earthlink.net>, Rod Brink <kq6f at comcast.net>, wayne burdick 
<n6kr at elecraft.com>, "Bob Wolbert, K6XX" <k6xx at cruzio.com>, Lyle Johnson 
<kk7p at wavecable.com>



Eric Swartz - WA6HHQ, Elecraft wrote:
> I agree.

Looks like we now have both a quorum *and* a veto-proof vote :-)

L
> e
> 
> 
> Lyle Johnson wrote:
>> Hello Bob!
>>
>>> If we all agree that the ALC voltage will be derived from analog 
>>> processed FWD power and MCU processed REFL power, PA current, and 
>>> Heatsink Temperature in some yet-to-be-defined SMOP way and that 
>>> these voltages will be summed and inverted with a simple voltage 
>>> divider rear panel or MENU adjustable potentiometer on the output and 
>>> that all of this circuitry will reside on the front panel with only a 
>>> single wire going to the IO board,  I will craft a schematic.
>>
>> Well, you and I agree.  Wayne's out of town, so we'll assume he 
>> agrees. since he can't deny it :-)
>>
>> Seems reasonable that we want FAST reaction time in the case of 
>> overdrive. I'm not certain that forward power will tell us that, but 
>> it seems like it could.
>>
>> The temperature stuff, reflected power stuff, etc., should be fast 
>> enough through the processor if you think the PA transistors can stand 
>> the effects of a sudden open or short when running full allowed power 
>> without damage until the processor can intervene.
>>
>> Lyle
> 
>