Tuning 40M on new Ameritron AL-80B Amp
 

The LOAD control on my Ameritron AL-80B has almost no peak on 40 meters.
Does this indicate something is bad?

The PLATE control peaks nicely on 40M.
The LOAD control peaks sharply on the other bands.
I'm getting full output power and good reports on 40M SSB.

I'm tuning the PLATE and LOAD controls for max output with 100W CW input,
using a Cantenna dummy load.

--
Bob ND9B

Tuning 40M on new Ameritron AL-80B Amp
 

"Bob D." wrote in message
...
The LOAD control on my Ameritron AL-80B has almost no peak on 40 meters.
Does this indicate something is bad?

The PLATE control peaks nicely on 40M.
The LOAD control peaks sharply on the other bands.
I'm getting full output power and good reports on 40M SSB.

I'm tuning the PLATE and LOAD controls for max output with 100W CW input,
using a Cantenna dummy load.

--
Bob ND9B

See page 13 in the manual. They can be downloaded from the Ameritron/MFJ
website.

Start with a dip in Plate current with PLATE adj.

What are you looking at for a "peak"? It should be tuned for maximum RF
output from the AMP. The peak should be shallow when properly loaded.

Because of the Q of the tank circuit, the adjustment is less sharp on the
lower frequencies.

Perhaps the LOAD adj. is too far clockwise. Be careful not to exceed grid
current. All this should be doable with less than 80w CW.

Tuning 40M on new Ameritron AL-80B Amp
 

I think I found the problem. The ALC SET control was set too low. It was
"capping" the output power. I couldn't see the LOAD peak because the ALC was
holding the power down.

--
Bob D.

"JB" wrote in message
...
"Bob D." wrote in message
...
The LOAD control on my Ameritron AL-80B has almost no peak on 40 meters.
Does this indicate something is bad?

The PLATE control peaks nicely on 40M.
The LOAD control peaks sharply on the other bands.
I'm getting full output power and good reports on 40M SSB.

I'm tuning the PLATE and LOAD controls for max output with 100W CW input,
using a Cantenna dummy load.

--
Bob ND9B

See page 13 in the manual. They can be downloaded from the Ameritron/MFJ
website.

Start with a dip in Plate current with PLATE adj.

What are you looking at for a "peak"? It should be tuned for maximum RF
output from the AMP. The peak should be shallow when properly loaded.

Because of the Q of the tank circuit, the adjustment is less sharp on the
lower frequencies.

Perhaps the LOAD adj. is too far clockwise. Be careful not to exceed grid
current. All this should be doable with less than 80w CW.

Tuning 40M on new Ameritron AL-80B Amp
 

"Bob D." wrote in message
...
I think I found the problem. The ALC SET control was set too low. It was
"capping" the output power. I couldn't see the LOAD peak because the ALC
was
holding the power down.

--
Bob D.

ALC on those takes a little getting used to.



"JB" wrote in message
...
"Bob D." wrote in message
...
The LOAD control on my Ameritron AL-80B has almost no peak on 40
meters.
Does this indicate something is bad?

The PLATE control peaks nicely on 40M.
The LOAD control peaks sharply on the other bands.
I'm getting full output power and good reports on 40M SSB.

I'm tuning the PLATE and LOAD controls for max output with 100W CW
input,
using a Cantenna dummy load.

--
Bob ND9B

See page 13 in the manual. They can be downloaded from the
Ameritron/MFJ
website.

Start with a dip in Plate current with PLATE adj.

What are you looking at for a "peak"? It should be tuned for maximum RF
output from the AMP. The peak should be shallow when properly loaded.

Because of the Q of the tank circuit, the adjustment is less sharp on
the
lower frequencies.

Perhaps the LOAD adj. is too far clockwise. Be careful not to exceed
grid
current. All this should be doable with less than 80w CW.