27 November 2012

Troubleshooting the biquad

First thing I checked on the biquad was the continuity of the coax+antenna setup. Electrically the quad is a short circuit, so measuring resistance across the antenna plug in the shack should be as close to 0 ohm as possible.
Instead my DVM was reading ~10 ohm "round-trip", but measuring at the bare coax cable end returned a fraction of ohm...
The antenna plug has a screw for ensuring electrical contact, which I promptly secured with a solder joint. Electrical resistance dropped to a more meaningful value and incoming signal from the local beacon increased. The biquad is still beaming away from it, I need to move the antenna to ther side of the house so that it will be facing the beacon, but currently my only properly terminated coax cable is running through a wall :-)

Next weekend there will be a 23cm contest, so I will have other on-the-air signals coming through.