Modification is also a problem as the rubber ducky is either integral or screwed on to a threaded stud, with no access to ground.
The result is a frustrated, repeater-bound ham. When a fellow ham in such a predicament set me pondering, realisation dawned that another rubber ducky could be used to couple the rig to an external antenna.
My own rig (which has a BNC connector!) was used to check it out. The coupling rubber ducky was mounted on the input of a homebrew SWR meter, with a dial lamp loading the output.
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| Rubber ducky coupling to a dial lamp |
The glow of the dial lamp indicated a coupling efficiency of about 20% (2.5W to 0.5W).
A 2m external antenna was then connected instead of the dial lamp.
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| Rubber ducky coupling to an external antenna |
On-the-air tests were successful. Comfortable simplex QSOs, not possible with the rubber ducky alone, were now possible.
Related post: SWR Meter - Easymatch
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