IC756 Pro3 Interfacing to PGXL

vk2on

Has anyone successfully interfaced the Pro3 with the PGXL. I am getting the 'RF Too Early' error and I don't love the idea of keying the amp with a foot switch. I have also checked the manuals for the amp and the radio and there seems to be tx delay options. If there interface box options?

Mike-VA3MW

If the IC-756ProIII doesn't have a TX Delay then it is highly recommend you have a foot switch key the PGXL first and then the PGXL key the radio. This is a problem with the actual radio.

Yes, not the prettiest solution, but that might be the only workaround.

vk2on

Thanks Mike. I cant find any tx delay setting unfortunately, despite google AI telling me there is one...I think that still needs some work. Thanks for the reply.

vk2on

There is one lingering question. Why is there the need to reconnect the PGXL back to the radio? Would you not actuate the foot switch slightly behind keying the radio to achieve the delay? I am not understanding the imperative for connecting back to the radio's send.

Gord-VA7GP

Mike has described a classic "sequencer" for TX. The problem of the amp not quite being ready has been around for many decades, and Mike's suggestion is tried-and-true. It has various forms, but generally:

you want to put your Amp into

TX first. Before anything else. Your receiver will briefly go "deaf" without an antenna, but there will be no harm.

Once the Amp is in TX, then you want to trigger your transmitter into TX. This is where the needed delay comes from - the radio has to start later, after the Amp is ready to accept RF.

Again, Mike describes a pretty sure-fire way to do this: key your Amp first, then have one of it's own internal relays trigger your IC756 into TX.

Other ways: you could use an external sequencer box, sometimes with several timed / delayed outputs to support antenna swithes, pre-amps, Amplifiers, etc. Or, Heil makes a foot-switch with two sequenced contact-closures, so this one device can first switch the Amp and then your transmitter (Heil FS-2)

HTH! Enjoy QRO