Sorry for the delay but I have been painting my barn. I will probably be painting for a few days. It has snowed here several times, in the past few weeks, so I am trying to make the best of the current weather.
Martin, thank you for such a quick detailed response.
I am clearly so out of touch! 'Computer Control' and 'Digital Modes' - I have no idea what those are, oh dear I am a dinosaur!
I hope it is still okay to plug in a mic and give a CQ call...
Don't worry, sooner or later you will learn about "Computer Control" and "Digital Modes". If you have ever tried CW, that is considered a digital mode now. If anything, I'm the dinosaur. This year is 50 years since my first anateur radio license.
While calling CQ isn't as common as it use to be, you can certainly call a CQ. A good portion of some bands (e.g. upper end of 40 meters) have been taken over by afternoon nets. But the lower end (7.125 - 7.175 MHz) is usually pretty open. In the evening, things are pretty clear and that's when the long distance contacts start coming in. But that is from my area (60 miles south of the Grand Canyon). Your area may differ. You just have to listen for a while to get a feel for the bands.
Please excuse my ignorance but I'm unclear as to what you mean by "Note that this is different than the RF cable sequence." if you could clarify that would be good.
It's a little hard to describe in just text, so I am attaching a simplified block diagram as I see the situation. That may help to clarify things.
The diagram shows antenna connections and the control signal connections. In the drawing you will notice that the RF connections go from the "Radio > Amp > ATU". But with the data connections they run "Radio > ATU > Amp". And that is because the ATU has a pass through connection.
As I have an interface lead with each of the atu and amp can one be simply connected between the ATU "Computer" and Amp ACC?
Both the ATU and the Amp need the control signals from the FT-817. They may use different signals, but the source of the signals only comes from one place, the FT-817. The ATU has multiple memories. These memories can store the correct settings for various bands (band data) and frequencies (reads frequency via C-IV). However, I am not sure what the Amp requires, as I don't have a manual for it. But my guess would be that it only needs the PTT signal or the "band data". Maybe both.
It may be possible to run the Amp without any connection to the FT-817 other than the RF. Then you would have to switch the bands manually on the AMP, when you change the FT-817.
I too have read some reviews on the amp outputs and was a little concerned until I read this gents efforts where he appears to say that the rig on power level setting 3 will restrict the output to a maximum of 30w an level 2 well under the recommended power input. Would 30watts do serious damage?
RF Eclectica: MX-P50M Amplifier for the FT817
Yes, I have read the link. He does a good job of explaining everything, but his configuration doesn't include a ATU. The ATU is the "weak link" in your setup. The manual for the ATU isn't much help. They simply states 20 watts "maximum power input" but don't state how that is measured.
I would recommend starting out with the level 2, to keep the power down. Then you might look into a manual tuner that can handle more power. Manual tuners can usually handle higher power and have a wider matching range. Once you get use to them they are easy to deal with. I bought my tuner at a hamfest for $15. The original owner burned out the SWR bridge and didn't want to fix it. But two diodes and a variable capacitor later, the tuner and SWR bridge was fully working again.
While I am 'rabbiting away' I'd be interested in any comments you or others may have with regards to my only real antenna option and it's location: I live on the south coast of the UK on the coastal plain, so no elevation. I do not have a chance of putting up a large array of antennas or long lengths of wire and so I resort to the 7 band cobweb. This will be mounted on my garage flat roof a mere 8ft above the ground! No chance of upsetting neighbours as it can't be seen due to my adjoining property (a bungalow) and surrounding shrubs! What are the chances of long distance contacts?!
This is a hard one to answer. I don't particularly have a antenna space problem, so I use wire antennas. While I don't have one, the cobweb seems to be a well liked antenna. And no matter how you mount it, it should work good. Maybe not as good as it would be on a 50 foot tower, but still good. but maybe someone else will have something to say about the cobweb antenna.
Long distance contacts is also a difficult question. Pulling in the big DX is often dependent on your skill and perseverance. The skill simply comes with time and patience. I may have a easier time hearing the distant stations because my elevation is 5,500 feet (1676 Meters), in a area that is considered high desert.
I'll be back in case you have more questions.
Martin - K7MEM
