[Amps] Ameritron AL-80A tuning question

[R.Measures]

On Oct 17, 2004, at 1:34 PM, NW7US, Tomas wrote:

> Hi,
>
> I am wondering if there is an error in the tuning instructions for the 
> Ameritron AL-80A in my copy of an old manual.
>
> It states:
>
> 8. Apply only enough drive to indicate a grid current of 50 mA or an 
> Ip of no more than 200 mA.  Tune the PLATE control for maximum grid 
> current.  It is normal for the plate current to dip at this point.  If 
> the grid current goes over 100 mA reduce the drive at once.  Unkey the 
> exciter.
>
> Ok - the part I am wondering about is "Tune the PLATE control for 
> maximum grid current."  It seems, in every band that I do this 
> procedure, there is no "maximum" on the grid meter - but there is ONE 
> spot that is a DIP in readings.  And, this is where the power out on 
> the watt meter increases.  In other words, no matter where I move the 
> PLATE control, the grid meter level stays about the same, except for 
> one tuning spot where the grid current DIPS - and this is where I 
> notice increase power out... so either the manaul is misleading me, or 
> I am doing something incorrectly.
>
> I'm just learning the Amp, and I am not an Amp user - this being my 
> first Ameritron, and second Amp I've ever operated.  I am wishing to 
> operate the Amp properly so I don't ruin the equipment.  Any pointers 
> would be appreciated.

Tomas - -To tune up a g-g amplifier, apply maximum drive, tune and load 
for maximum relative output.   Observe anode-I.  It should not exceed 
the rated maximum.  If it does and you have an adjustable output level 
transceiver, adjust the level for the rated max anode-I and retune.  If 
your transceiver output is not adjustable, add some R in series with 
the cathode coupling C so that the tube will not be over driven.
-  end
>
> Thanks,
>
> 73 de Tomas, NW7US (AAR0JA/AAA0WA)
>
> : Propagation Editor for CQ, CQ VHF, and Popular Communications :
> : Creator of live propagation center - http://prop.hfradio.org/ :
> : Member, US Army Miltary Affiliate Radio Service (MARS) AAR0JA :
> : 122.93W 47.67N / Brinnon, Washington USA - CN87 - CW/SSB/DIGI :
> : Website, software, database design - http://newwebmakers.com/ :
> : Washington State Army MARS, State Army MARS Director - AAA0WA :
> : 10x56526, FISTS 7055, FISTS NW 57,  AR Lighthouse Society 144 :
> _______________________________________________
> Amps mailing list
> Amps at contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
>
>

Richard L. Measures, AG6K, 805.386.3734.  www.somis.org