i have one of those is came with my yaht boy 400 * this was the grundig model 
that goes into the antenna jack * they do help improve reception *
sw radio is amazing though what sometimes helps and somedays/nights alls you 
need is your radio's whip * i myself run a 120' longwire antenna that seems 
to working just fine but on nights for instance that you have a thunder storm 
yes in january in pa. i can see where that zebco 200 will come in handy 
(fishing reel reference) * enjoy your listening *
--- Maximus 2.02
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