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Messages - vwflyer

#16
QuoteThe main advantage of qrp rigs is power drain. Qro rigs in qrp mode drain much more power than pure qrp rigs.

That's true. The 817 realistically draws what on receive, 350ma? Most QRO rigs can be made to draw something in the area of 1 amp if you turn down or off some settings. That's a realistic difference of a solid 500-700ma. Figure 600ma at 12.5 volts and we have 7.5 watts of power savings.

Of course the oft-quoted downside of QRP is it's less reliable ability to be heard. To help overcome this handicap, more efficient modes are used, i.e. CW and digital. The problem with CW is that it kind of requires that the operator learn it. The problem with digital is that it requires a separate computing device, which also draws juice, cutting into your power savings. A laptop is the most convenient platform for working digital but it's also the most power hungry. A smartphone is the least power hungry but kind of inconvenient with it's small interface. A tablet is often chosen as a happy medium. The screen of a tablet is the most power hungry part of it, and unfortunately, outdoor/portable use generally means that the screen brightness has to be turned up to see it in the daylight. An iPad Mini at full screen brightness has been measured to draw about 4.5 watts. This makes your power savings only about 3 watts over a QRO rig that doesn't use the iPad. 

So at a battery voltage of about 12.5 volts that comes to an additional 240ma draw on the battery that a QRO rig has over a QRP rig coupled with an iPad Mini. That means that if you want to be able to have 8 hours of receive/monitor time, you'd need a battery that was about 2ah bigger to do so with a QRO rig vs a QRP rig/iPad combo. The difference in size and weight between a 7ah battery and a 9ah battery is pretty minimal and may well be worth it to have the option of going QRO when you need it.

I'm not saying that the 817 is a bad choice. I would certainly own one if I could convince myself that I needed one, and I almost have on a few occasions. It does everything under the sun and coupled with a small power amp can certainly take the place of a shack rig. It's an all around work horse. But to make it a reliable mode of communications, one has to either learn CW or concede that it's power savings over a QRO rig are going to be modest.
#17
New To Radio / Re: QRP from a beginners view
June 02, 2018, 11:50:48 AM
That's true, they do, because there is no electronic keyer involved. Sides swipers and cuties are also aloud. Pretty much anything that doesn't involve electronics. But straight keys still rule there and whatever type of manual key is being used, speeds are still relatively slow.
#18
New To Radio / Re: QRP from a beginners view
June 01, 2018, 11:00:15 PM
Congrats on your ft817 purchase. I've never owned one but I don't think you can go wrong with one.

I have done some QRP SSB though, and I can say, it's not for the impatient. Contacts are rewarding and as Gil says, with practice you will make more and more. There are tricks to QRP, like calling a guy right after he finishes a QSO with someone else (tail ending), checking into nets, break into a rag chew where the people sound friendly and inviting, answering other's CQ's rather than sending one yourself.

A good way to test the abilities of your station is to make contacts with people you know are listening for you. Set up a sked with someone on this forum or any other of the numerous web forums. Send an email to someone in your local ham club asking if he's free for a sked. Even during this time of low sunspots, 80 meters NVIS works wonders, even at QRP, for local and regional contacts. Or activate a SOTA summit and spot yourself. You will be the center of a pileup in no time and most of your chasers will give you realistic signal reports.

A great forum to set up skeds with people is the Straight Key Century Club (SKCC). They have a webpage just for setting up skeds with other people who use a straight key. It's a great way to get your feet wet with CW. Since everyone is using a manual key, the speeds are slow and the people patient. Plus, for QRP, CW has several db advantage over SSB and your experience making CW QRP contacts will be more akin to making SSB contacts at 100 watts.

You've got a great setup. Stick to it and don't get discouraged. If you're not careful it may become an addiction.
#19
Gil, Thanks so much for pointing out what should have been obvious. I feel like a fool for not thinking of it myself. It works like a charm. If I run the coax inside the bead without any loops I have to have the bead up by the base of the antenna. If I loop it through just once (like in the photo) it gives me perfect SWR on the HB-1B meter no matter where it is on along the coax. It even shows low SWR over a much wider range of the band.

#20
Good idea Gil!
I'll try that today.
#21
Thanks Gil,
I put one wrap back on the inductor and tried it with both lengths of coax and my HB-1B. It seems that I  can operate the lower part of the CW portion when using 3 feet of coax 7.025-7.055 and I can operate the upper portion of the CW band with 9 feet of coax 7.055-7.100. Have other people experienced such a narrow Q on 40 meters? Perhaps I should buy QRPGuys QRP tuner and use that when using this antenna on 40 meters. I don't think I will use my MTR3B on 40 meters with this antenna without a tuner. I can't risk running a high SWR and not know it with that rig.
#22
Antennas / Tuning the QRPGuys vertical tribander
May 30, 2018, 10:34:44 PM
Hey guys,
After reading many positive  comments here about the QRPGuys vertical tribander I decided to get one. It went together quickly and after a little adjustment got it working with very low SWR on 20 and 30 meters. I was using the built in SWR meter on my YouKits HB-1B. I know not the most accurate but it's what I have for QRP levels. Resonate on 40 meters was way to low so I wound up removing 2 wraps from the inductor and that got it up to where I need it. I was using just a short 3 foot coax jumper to connect to the rig. I decided to add 6 feet of coax to make sure it doesn't change anything. On 20 and 30 it didn't change much but on 40 it is now resonate way up in the voice part of the band with the extra length of coax attached. That is, unless I have my hand under the back of the rig, then the resonate freq comes back down to the CW part of the band. I'm thinking that I will probably operate this antenna with longer pieces of coax since I don't want to be tethered so close the the base of the antenna to operate. I can add a wrap or two back onto the toroid since I haven't yet snipped off the excess I had after taking two wraps off but that part of the wire is no longer insulated. What happens if uninsulated magnetic wire rests against the toroid? It will be fine as long as it doesn't come into contact with uninsulated wrap right next to it right? 
#23
Hi Phillip,
Welcome!
Suggesting a first rig for someone is hard to do. Of course you know the answer will be "it depends". I'm partial to the Yaesu ft-450D as a starter rig to go in one's shack. It is one of the best bangs for the buck with a good selection of filters and DSP. You can get one for under $500 like new. To get an icom with a similar set of features you'd have to spend almost twice that. It also has a surprisingly low current draw on receive for a 100 watt rig. It's not that big and so can work well as a field day rig but it's a bit too big for real portable ops. I think a KX3 is about as big as I would go for a rig to go in a backpack. For ultra portable I like my MTR-3B. It's CW only but boy is it small.
#24
That sounds like an awesome nab. If you're like me, you'll be nervous as hell on that first CW QSO but the rush will be well worth it.
#25
Morse Code / Re: Can Morse Code Still Save You?
May 22, 2018, 03:08:48 PM
Gil, you're a very eloquent writer in English. Much better than I and English is my first language. No typos or grammar errors jumped out at me but I should let my wife read it if you want a better editor's eyes. Engaging intro and great points throughout.
#26
Morse Code / Re: XXX
May 21, 2018, 12:52:08 PM
SOS recognition by skimmers would be very useful indeed. It's a shame it's not implemented. With the miniaturization of HF rigs and subsiquent popularization of portable ops including popular activities like SOTA and POTA  more and more people are taking radios to isolated areas these days. This has also lead to a renewed interest in CW among hams. As good neighbors and safety conscious hams, we should see CW as a valuable and viable way for the growing number of portable operators to call for assistance. Skimmers should be made to recognize distress calls and perhaps some skilled and charismatic writer should campaign to revive the awareness of X X X. An article in QRZ magazine, on their webpage, on some popular CW, portable ops, and general ham radio podcasts. Spread the awareness and make X X X a useful tool in the portable operator's toolbox.
#27
Morse Code / XXX
May 20, 2018, 11:35:53 PM
No, this post is not about Vin Diesel or adult movies. Rather, it's a question concerning the old practice of sending X X X in CW for Pan Pan, which is a call for assistance in non-life threatening situations. As a pilot I'm familiar with Pan Pan and I was curious if there was a way to call it in CW. So I googled it and discovered it was three x's sent as distinct letters. I've been messing around in CW for a few years now and never have come across this yet so it is not common knowledge like SOS is. I got to thinking about it as I was driving through a really isolated stretch of mountain roads last week, miles from cell service and thought that a way of getting the attention of a ham on the CW bands would be real handy if I had a breakdown and needed to have a ham relay a message for me to my wife to let her know about it and send some help if needed. I know SOS would bust a pileup and get a dozen of willing helpers in seconds. Do you think sending X X X would have any affect at all or am I better off just calling CQ HELP or something like that?
#28
Great! Thanks Gil!
#29
Hey Gil,
Did you find a good enclosure for your 80 meter rig? I've almost got mine done but I don't want to put on the components that poke out until I settle on a case.
#30
Digital Modes / Re: FT8 digital comms mode
April 15, 2018, 11:35:54 AM
QuoteWhat's needed in a prepping digital mode is something that can be left unattended and save messages...
Here's my limited understanding of store and forward systems. If somebody wants to correct me or expound, I'm anxious to learn.
Every store and forward needs a running radio connected to a server. Most of them these days use servers on the internet so when the internet goes down so does the server. Some have local servers, like many Packet radio repeaters designed to work without the grid or internet. Winlink and APRS can use local servers as well but to my knowledge, most use internet servers. In any case a grid down situation is going to require a powered radio with a local server that can run without grid power. Having someone else do that for you can be convenient in that you don't have to leave your computer and radio running all the time. But then the success of you getting the message depends on someone else's setup working.
For keeping messages locally at my own QTH, using my own radio and computer, I would currently go with FSQ. It's designed for this. Messages can be sent directly to you and give you an alert when someone tries to contact you. The messages are stored so long as the software is running.