The Al-80A is notorious for the small little nylon connector that connects the
load cap to the vernier control to split and the cap dos not advance when you
turn the laod knob.? Bet that s your problem.? Seen it several times in my
repairs on that amp.? Lou W1QJ
-----Original Message-----
From: Carl <km1h@jeremy.mv.com>
To: Lee Buller <k0wa@swbell.net>; amps@contesting.com
Sent: Thu, 20 Nov 2008 12:19 pm
Subject: Re: [Amps] Strange Loading Issue
Id start the next step using a dummy load and investigate the bandswitch
wiring. There is a fixed 170 pf C used on 40M but with 800pf variable I
cant see that being the problem. More likely the load cap switch wafer
has zapped or a crystalized solder joint.
Carl
KM1H
----- Original Message -----
From: "Lee Buller" <k0wa@swbell.net>
To: <amps@contesting.com>
Sent: Thursday, November 20, 2008 10:10 AM
Subject: [Amps] Strange Loading Issue
My friend has a AL80A...generic amplifier. In fact, I sold it to him. He
was having some issues loading it so I went over to his house and took a
look. This amp worked great for me for about 5 years or so.
We were going into a 40 meter antenna which gave an SWR reading of 1.1
to 1. Very low. Seemed to me to be OK.....
The amp would go to 400 mills and 160-170 mills on the grid with about
73 watts of drive. Around 600 watts. I could dip the plate and see the
peak on the watt meter. Seems reasonable to me. But, the load control on
the amp had no effect on the grid current or the plate current. I could
almost put the load control anywhere and it would not affect the meters
what so ever. Now, this had never happened to me before when I owned the
amp. The load control was .... working normally to my thinking and I
could adjust the load of the amp and bring down the grid current to
around 120 mills. Kind of has be baffled as to why it is doing this. I
do not think it is normal.
Does this "august" group have any words of wisdom?
Lee - K0WA
In our day and age it seems that Common Sense is in short supply. If
you don't have any Common Sense - get some Common Sense and use it. If
you can't find any Common Sense, ask for help from somebody who has some
Common Sense. Is Common Sense divine?
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