[TenTec] re Ten Tec amps and ALC

k4dlj at bellsouth.net k4dlj at bellsouth.net
Tue Aug 24 11:19:47 EDT 2004


Hi Don, 
Coming to Shelby? 
Have that last section of AB-105 which I will put on the trailer if you want? 
73 de Dave K4DLJ
> 
> From: don daso <k4za at juno.com>
> Date: 2004/08/19 Thu PM 08:20:15 EDT
> To: tentec at contesting.com
> Subject: Re: [TenTec] re Ten Tec amps and ALC
> 
> The ACOM is 0 to -11volts, if my memory of conversations w/the gang
> @K4JA's station is correct
> 
> Automatic Drive Level, known as ALC for short, was originally designed to
> limit grid current, preventing overdrive by applying a negative DC
> voltage "back" to the exciter/transmitter, especially useful in tetrode
> amp situations.
> 
> Today, our amps require a drive level between 50-80 W for legal limit. 
> You can use ALC or not.
> 
> Circuits can be internal or external; they can be set by the op, or
> automatic.  
> 
> If external ALC isn't used, the output of the exciter/transmitter should
> be reduced using the power output control to avoid over-driving the grids
> of the amp.  Some ALC circuits (like the Emtron amp) produce a negative
> 1-10Volts, proportional to the grid current, when overdriving the
> tube(s).  It's not as easy to over-drive, say, a pair of 3-500Zs w/a
> typical 100W rig....
> 
> And today, not all transceivers (which have generally replaced
> exciters/transmitters) have a direct ALC jack or output jack.  Recent
> KENWOOD rigs, for instance, have the ALC on a DIN-plug (the REMOTE jack),
> while the FT-1000 has one.
> 
> N1EU once had a good write up on ALC circuits on his web-site (along
> w/lots of other useful information on contesting/DXing/modern rigs).  I'm
> sure a quick Google search would turn up that link.
> 
> I gave up using ALC when I began using triodes in grounded grid.  Never
> had a rig capable of over-drive.
> 
> GL & vy 73 de Don K4ZA
> _______________________________________________
> TenTec mailing list
> TenTec at contesting.com
> http://lists.contesting.com/mailman/listinfo/tentec
> 



More information about the TenTec mailing list