If you're like KF6BKR and I, you discovered that the best way to work field day is with two operators per radio - one to do the talking and one to do the logging. And if your field day is like ours, then you also discovered that between the generators, other radios blaring, and people just plain standing around yakking, it's next to impossible to talk to each other, let alone hear that QRP station at the bottom of a fifteen meter pile up. Worse, your radio's microphone picks up all this background noise just as well as your ears, so all the unfortunate operators on the other end of your QSOs are subjected to the same cacophony you are.
Enter the KF6TBN contest station which allows you to use an aircraft communications quality headset to seal out the outside noise while still being able to hear your partner perfectly. Better yet, these headsets feature a noise canceling microphone which isolates your voice from the environmental noise, so the operator on the distant end of your QSO hears only you. We used the TR-2000 aviation headset from the Warren Gregoire company, but other manufacturers make models which will work just as well. There's enough real QRM on the bands without adding more before the sound even gets to the radio!
With the KF6TBN contest station, both operators hear the radio's receive audio in their headsets and either operator can transmit using their boom microphone. The radio's transmitter is keyed by a footswitch or hand held button, such as Warren Gregoire's PTT-2000 or FT-2000. The contest station also works as an intercom so that the two operators can speak to each other at any time, without transmitting, thru their microphones and headsets. Finally, the contest station provides a third, monitor, output which can drive extra headphones, a tape recorder, or even a speaker so that bystanders can hear the action.
Each operator's headset connection features an independent headset volume control, an independent microphone level control, and an intercom/radio "balance" control. The separate microphone level controls allow the transmitter modulation to be adjusted to consistent levels even if one operator speaks quietly while has the habit of shouting into her mike. The intercom/radio control allows each operator to adjust the relative levels of the intercom audio and receive audio heard in his or her headset to suit their taste.
Both operators have their own independent push to talk inputs, however only the operator who pushes his or her PTT (the "transmitting" operator) will be heard on the transmitter. The other operator (the "non-transmitting" one) may still speak to the transmitting operator via the intercom, however the non-transmitting operator's voice will not be heard on the air. This allows the logging operator to prompt the talking one (e.g. "Get his report!" or "November-Six-Papa-what????") without confusing the radio audience.
The contest station's final section, the monitor connection, provides a couple of extra headphone outputs with no microphone inputs. Visitors or observers may plug in headphones here to listen in on the action, or you can even plug in a small speaker to allow bystanders to listen in. The monitor output has a volume control and an intercom/radio "balance" control just like the operator connections, but of course no microphone level adjustment. The monitor also has a line level output which can be used to feed a tape recorder for logging purposes.
The KF6TBN contest station connects to your radio's audio output (either speaker or line level), microphone input, and PTT control. It can be used with pretty much any radio, from the mightiest Collins rig to the tiniest HT, but you'll need to make up your own cables. The contest station features connections for two operator headsets, two operator PTT switches, two monitor headphones, and a line level monitor output. 12V DC power is required to operate the contest station.
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October 05, 2011.