I see several possibilities.
A NCL-2000 running on the low power tap will drive to a respectable power
level depending on actual drive. At the IC-703's 10W rating figure on
600-800W out. Running it at less than ratings is one easy way of keeping the
tubes happy.
Johnson Thunderbolt, far from expensive but rather bulky and heavy.
P&H LA-400 will get you to the next stage to drive a bigger GG amp
A modified CB amp. Most use a single GG stage to take 4-5W to drive 2-4 more
of the same. Easy to make over to 80-10M with acceptable linearity. Finding
affordable tubes may require using the higher filament voltage versions and
a new filament transformer or a DC bench type PS.
SS....yuk (-;
Carl
KM1H
----- Original Message -----
From: "k7fm" <k7fm@teleport.com>
To: "Eric Mynes" <kc8wzb@gmail.com>; <amps@contesting.com>
Sent: Monday, October 04, 2010 11:24 PM
Subject: Re: [Amps] Questions from a beginner
> This is in response to Eric, wanting to add an amplifier to his Icom 703+.
>
> Eric, there is a major problem. The Icom 703+ is a qrp rig, with an
> output
> of 5 or 10 watts. The last I heard, amplifiers sold since about 1980 do
> not
> operate at the 5 - 10 watt level. That is because the chicken banders
> were
> using those amplifiers to illegally amplify 11 meter signals.
>
> Most of the amps sold since then require 50 to 100 watts of drive.
>
> So, your options are limited. Some military/commercial amps will drive
> with
> your 5 - 10 watts, but they are rarer than the ham amps and will require
> understand them. Ten-Tec sold a small amp that operated on their
> argonaut,
> to boost the signal to 50 watts. But, they are quite rare.
>
> The Central Electronics 600L would work ok - but they are not common.
>
> Although this forum is about amplifiers, much of the discussion is bent
> toward the other end of the power spectrum. For this group, 100 - 200
> watts
> is qrp.
>
> At the power level , you may be better off building a 5 - 100 watt solid
> state amplifier - but you will have to learn about solid state circuits
> and
> building.
>
> 73, Colin K7FM
>
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