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[AMPS] Amp opinion/infomation requested ASAP!!

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Subject: [AMPS] Amp opinion/infomation requested ASAP!!
From: measures@vc.net (Rich Measures)
Date: Tue, 30 Mar 1999 11:13:46 -0800


>
>Vic Rosenthal wrote:
>
>>  I have been
>> successfully using an old Johnson 275-watt (AM) matchbox to feed a 40-m 
>> dipole, ladder-line fed, on all bands at 800w CW for some time.  

?  I ran my E. F. Johnson 275w Matchbox at 1500w ssb pep with no sparks,  
feeding a ladder-line/ dipole..  However, the Z matching range was so 
limited that I sold the Matchbox.  

>
>> I suspect that the KW version would be good for considerably more than 1500 
watts PEP.
>
?  I've heard of cases where it reportedly handled 3k pep-ssb, which is 
semi close to a kW AM. .  

>I forgot to add, for those who don't know, that the Matchboxes are 
>link-coupled
>parallel-tuned, balanced circuits.  The 4 to 1 balun in most modern tuners is
>very inefficient when the SWR on a balanced line gets above 3 to 1 or so.  
>These
>tuners are really designed for coax or for balanced lines 

?  these tuners are typically T-networks, which are ideal for end-feeding 
high-Z antennas such as the Hertz.    A Matchbox won't.  

-  cheers, Vic.  


Rich...

R. L. Measures, 805-386-3734, AG6K, www.vcnet.com/measures  


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