Greetings fellow Elecrafters, I'm sorry for emailing this question to the group, but the folks on this reflector are a smart bunch. Maybe someone could give me some advice or suggestions. I posted this question to the Icom 756 Pro III group and QRZ, but no one seems to have an answer.
I'm diagnosing a problem with an Icom 756 Pro III. It's tuner's "insertion loss" is quite high. For example, when the tuner is off, sending an unmodulated FSK carrier shows the transceiver putting out 100W. As soon as the tuner is activated, power drops by 10-15%. That's a lot of power being dissipated somewhere, and I don't think it's good especially for 100% duty cycle modes. It doesn't matter whether the Icom is connected to a dummy load or resonant antenna. The results are always the same on every band. In comparison, the K3's tuner seems to be incredibly efficient. If there is a loss of output power on the K3 whenever its tuner is inline, it's not noticeable. More often than not, power increases when the K3 finds a good impedence match. I've gone as far as recalibrating the Icom's tuner. This was done by terminating the remote jack on the rear panel, and entering the tuner service mode. The tuner calibration process completed with no errors reported by the Pro3. Any suggestions? I'm going to call Icom support tomorrow to see what they say. - 73 de James K2QI President UNARC/4U1UN ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
