[Amps] Antenna traps

[Joe Isabella]

  The Alpha-Deltas seem to be pretty stout, but they are somewhat unconventional in that they don't use discreet capacitors.  The coil's internal capacitance does it for them.  I used their 80/40 shorty dipole for several years without hurting the traps.  However, I added a 1:1 current balun at the feedpoint and replaced the end insulators several times.  The reason the ends went is that I used my tuner to use the antenna out of resonance -- probably okay at 100W, but not at legal limit.  I now use a full-length dipole fed with 450 ohm twin lead.  So far, no problems.
   
  Joe, N3JI

Osten B Magnusson <sm5dqc at areteadsl.se> wrote:
  
I have also bought Unadilla 80 CW traps for a wire vertical, 
have burnt two at 700 watts - I thought there was something
wrong with the first one, but the same thing happened also 
with the second one... I have not yet made an autopsy, but
will do and see what's inside that blue melting plastic.

73 de Osten SM5DQC sm5dqc at areteadsl.se


----- Original Message ----- 
From: "Gene Bigham" 
To: 
Sent: Tuesday, December 13, 2005 11:16 PM
Subject: [Amps] Antenna traps


>I know this is not about amplifiers, except for being able to use one on a 
> trapped antenna, but has anyone found a set of traps for 40 and 80 that can 
> handle a legal amplifier output?
> I have now fried two sets of 40 traps by Unadilla and one set of 80's which 
> the new replacements have not been tried at power yet.
> The old traps shorted through the cap insulating material, they were old but 
> never used, so I thought the epoxy was just old. The new ones have melted 
> the blue insulator on which the coil is wound on these 40 meter traps with 
> 500 watts power level.
> I tuned the antenna to resonance of 1:2 to 1 SWR, worked several stations, 
> increased power level and after two hours and 500 watts started seeing swr 
> creep up slow then rapid. Examination showed the blue material melted and 
> oozed between coil turns and the coils are now also intermittent.
> I need some bullet proof traps.
> Any ideas?
> Thanks in advance
> Gene Bigham
> KB0GU 
> 
> _______________________________________________
> Amps mailing list
> Amps at contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
_______________________________________________
Amps mailing list
Amps at contesting.com
http://lists.contesting.com/mailman/listinfo/amps
  



			
---------------------------------
Yahoo! Shopping
 Find Great Deals on Holiday Gifts at Yahoo! Shopping