[Amps] Questions from a beginner

[Carl]

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 at teleport.com>
To: "Eric Mynes" <kc8wzb at gmail.com>; <amps at 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
>
> _______________________________________________
> Amps mailing list
> Amps at contesting.com
> http://lists.contesting.com/mailman/listinfo/amps