[Elecraft] ALC and the K3

[Dave Cole (NK7Z)]

Don,

Thank you for the information here...  My amp, (the ALS-1306, solid 
state), I believe does use the ALC to shut things down in the event of a 
failure of some sort...

Here is a cut from the ALS-1306 blurb page:

"Output power is automatically reduced to prevent amplifier damage by 
controlling ALC to exciter."

That does not tell me exactly what triggers ALC action, but it does tell 
me that they are using ALC as a form of protection...  As such I want to 
use ALC.

I think I like your idea of adjusting the Amp to not issue ALC during 
normal operation, that way, if something goes way wrong, the ALC may 
still be able to shut things down.  Fortunately the Amp has both 
metered, and front panel adjustable ALC.

I think I will also adjust the Max power for all bands as well...  I 
just finished the install of the SWR/signal monitor thing-a-mabob in my 
P3.  I also have an outboard demod I built, which I can feed into the 
scope to do a bit of monitoring during setup...

Too all the rest of the folks that made suggestions thank you as well!!

73s and thanks,
Dave
NK7Z
http://www.nk7z.net

On 12/21/2017 11:01 AM, Don Wilhelm wrote:
> Dave,
> 
> The K3 does not overshoot due to the way output power is controlled (it 
> is different than other amateur transceivers in that regard.
> So unless the amplifier contains protective circuits which activate the 
> ALC for excessive SWR or other amplifier faults, there is no need to 
> connect the ALC line.  Even if the amp contains such protective 
> circuits, adjust the ALC in the amp so it does not activate with normal 
> operation.
> Set the power so the amplifier is not overdriven.
> 
> If the ALC is activated in normal operation you will be creating 
> excessive IMD in your transmit signal - you can hear a lot of that going 
> on during a contest weekend.
> 
> The K3 has a menu setting (PWR SET) that can allow you to set the 
> maximum power on a per-band basis.  You can use that to avoid 
> overdriving the amplifier.
> 
> 73,
> Don W3FPR
> 
> 
> 
> On 12/21/2017 12:45 PM, Dave Cole (NK7Z) wrote:
>> I want to run ALC for my amp if for no other reason to protect the amp 
>> from overpower events.  I understand Elecraft does not recommend the 
>> use of ALC...
>>
>> Exactly why is that?
>>