[posting here for WAHTF]
Hi all, I'm going to try NVIS around Seattle greater area at 40m with the Buddipole close to the ground (4 to 8 ft) this Sunday.
If anybody is up for a QSO and radio checks, I'm going to be at 7.213 and 7.285 from 8PM to 10PM Pacific Daylight Time. It would be good to confirm signals and distance.
This is my first newbie QSO attempt ... :-) I've diligently crawled my way on from technician to general license (well a year ago or so), and just now got onto HF after saving enough for the radio.
I tried out both the Buddipole and Buddistick configuration (40m, and 20m). Tuning was really easy, I followed Buddistick's tuning by ear instructions. I tuned for a lower frequency at eye level, and then confirmed the SWR after raising the antenna.
It was of course easier to tune by ear for the Buddistick (one coil, whip, and radial). The Buddipole just took a bit longer (used the TRSB tuning guide).
My goal is really more for emcomm than hours sitting for QSL's (too many yard and house chores first to get to on a weekend). I'm pretty sure I'll get hooked on DX, QRP, and contesting in no time once I have a few contacts :-)
Cheers! CharlieZ, KE7***.
I spent 10 years in the Army and never saw that many acronyms, in one spot.
I Agree, WTF??????
It's Ham Radio speak (no, not the pork meat ham).
NVIS = near vertical incident skywave (means the radio frequency bounces almost straight up and then down). It helps provide local communications without having to use repeaters).
QSO = arranging a radio contact.
QSL = making radio contact.
ETA: QRP = making low power radio contact (5-10watts). TRSB = triple ratio something balun. DX = making long range radio contacts (say from Seattle to Japan).
I'll see if I can get my tuner working tomorrow.
Have a fullwave 160M loop here about 15 feet off the ground.
If I can get it to load up it should make a great NVIS antenna for 40m..
I will QSX on those frequencies you listed with a 5 kHz + - shift for QRM if
it is necessary to QSY. Will be listening for your CQ.
QTH is Winthrop and I do not have an RF amplifier so no QRO from this station.
Who knows we might have a Q5 copy and be able to go QRP for kicks.
I will attempt to meet your sked and hopefully there will not be
to much QSB or QRN. It will be nice to finally have a QSO with
one of the WAHTF folks. I'm sorta lazy so doubtful I will QSL via USPS.Heh, )
I bet you two have seen plenty of NVIS antennas and did not even know it.
You may have even helped set them up out in the field.
Anyway, Im working during that time, but I get home around midnight. maybe try something a little earlier. think about 75/80M
I'm also up now until 12PM. I'll call CQ also at 6PM for R-32.
That ^ was the 280000 post in the WAHTF!
And it was a total waste...
I will be at work, so him calling CQ will result in.....
I have been calling on 7213 (LSB)... No luck. I will keep the radio on till I goto work in about an hour.
I am building this right now..
I hope to have it finished up by next weekend.Home Brew of the Military AS-2259 NVIS antenna
Darn, we missed each other by about 30 minutes. I turned off the around 12noon
I won't call CQ for R-32 at 6PM then ... and will stick to the 8PM-10PM schedule.
I got the tuning figured out so can deploy the antenna and rig in about 30 minutes in my backyard now (about 16' mast Buddipole in 40m config), so have to guy the mast (last time the thing fell and chopped off both whips).
Slowly but surely, we'll get WAHTF contacts!
Allright!!! I'll be calling.
Well, it didn't quite work out the way I intended. I made contact but not locally, it was to San Jose
FT 897D, with Buddipole (horizontal), whips fully extended, no taps, no balun, on aluminum painter's pole as a mast 16 feet high. The Buddipole didn't want to tune to 7.213 at 4, 8, or 16 feet above ground. I had to use my antenna tuner.
bummer, but it is nice to know you got down to California.
Im spinning around 40 right now, listening to 7215 at the moment.
I listened up and gave a call every 30 minutes or so from 4pm-10pm,
on 7.213 and 7.285. Also listened some on 20m so might have missed you then.
After about 7pm the propagation started to open up to night time propagation
and I started to hear stations from back east such as Indiana and further.
Static crashes at about 7-9 S units. This 160M full wave loop (over 500 feet of electric
fence wire) really hears well with that much capture area. Well, better luck next time.
I thought I might have heard you a time or two but it was pretty far down in the noise.
We might have a bit better luck on 75m or even 160M if you can put up some wire.
You can zig zag the wire around with little ill effect
if the space is tight.
Start talking about your set up above....
I have 5 acres, and LOTS of this electric fence wire. I also have it set up all along all of the fences on my property, I was thinking about trying to use it for something. The stuff that is up right now is no longer hooked up to the hotbox, but it is still hanging about 4' off the deck.
Bruiser, good to know you were listening and calling out, I called for CQ once every 5 minutes from 8PM to 10PM.
I had my dipole lengthwise east to west. You're approx north east of me in Seattle greater area.
Between the dipole propagation direction, the cascades range, and my contact ending up in San Jose, I can say that my NVIS attempt is a bust
If NVIS was working, I should have been able to reach you (even if the dipole propagation eastward was a problem).
I'll try the fence antenna (I don't have 500 feet circumference around the house), but I'll try my wire dipole low on the fence (4-5 feet) and see if I can tune 80-160m (it can tune to 40m).
A 160M NVIS antenna probably should be up around 40' - 60' for better results, ie, more ground loss if you get to close to the ground. (15'-25' for 75m, 7'-15' for 40m, since
the actually ground can vary by soil type, water table, etc.. its not really critical.)
To low heats the worms up and wastes the RF, the antenna will tend to use less
wire due to ground capacitance and also will be more widebanded,
ie, you find yourself trimming off 3' (160m-75m) at a whack when tuning and end up
scratching your head about how your calculations
for the wire length could be off that far.
Since I don't have any biological antenna supports (aka, trees) handy I just strapped some unused fence rails (18' lodgepoles) to the fence posts out in the back pasture.
Then since we have lots of baling twine around I used those for the insulators. Basically laid the wire out, looped the twine over the wire, tied to the top of the rails/supports before
strapping to existing fence posts. Leave the twine kinda long and you can just spin them to tighten up the wire. I ended up using 7 supports. Had some RG-8 handy that the dog had chewed an end off of so just stripped it back a bit more, then wire nut attached each side of electric fence wire to shield
and center wire. Used the twine in about a 12" loop to strain relief the wire/coax
connection. The baling twine is free so that is what I used for insulators. I run that coax to
the radio room and into an antenna tuner so that I can use it multiband without damaging
the transmitter. Not the most optimized set up but it sends a decent signal out.
Gooches law: 'RF gotta go somewhere'.hereOh, might want to put a neon bulb across it and a good 10K - 100k resistor to ground to
drain the static charge. Heard something arcing last winter inside the antenna tuner.
Let me tell ya.. When you disconnect the coax to see whats arcing it will give you a hell
of a jolt off of snow static and wind charge!heMy inverted V/ fan dipole for 75m/160m is a little higher and seems to be heard a little
bit better. Center of that is at 35' with the ends at 12' off the ground.
By the way a fan dipole is a great way to go multiband without a tuner.
Just attach multi dipoles to the same feed point. Offset them a little bit (5'-20') when
you string the ends out so that they don't interact as much when you trim to frequency of
interest. Oh, and a 160m dipole works great at 17m.
For receive only a beverage antenna is the cats meow. With the correct tuning circuitry
you can even make them directional with steerable nulls. Takes alot of wire, mounted out
of the path of critters like deer (8' high should do it) So if you have an existing straight
run of fencing you can run it along the top of the fence. I am (back burner project) going to cut some pvc pipes about 5' long and slip over the top of an existing barb wire fence
with a run of electric fence wire on top of that. Our house is sorta in a corner of a 25 acre fenced in property so should be able to run 1000' n/s and e/w. Going to make sure those
buggers have a -really- good static drain and disconnect outside of the house.
A beverage antenna works on the principal of being multi wavelengths long, since the
speed of rf is slower thru metal then free space (velocity factor) you end up with an averaging effect so that fading of signal is not as noticeable. I used to be into VLF, LF and MW DXing and have a little bit of esoteric knowledge for lowband receiving, emphasis on the little bit, some of those MWdxers are -really- into listening to some 25W station in the middle of Mongolia, sometimes you get about 45 seconds when the conditions are justttt right to hear and ID the dx station.
By the way if anyone over on that side of the ridge wants to experiment with the lowfer
band I would love to take part.
Lowfer band is an unlicensed band at 160kHz-190khz, multi mode (usually build your own)
1 Watt transmitter with 50' max wire. Sounds hard but +1000 miles is possible.
R-32, just hook that fence up to your radio and see what you get.. I put two strands on our fence so I can disconnect one and use it if I want.
A SGC237 autocoupler would probably do the trick for multiband use.
That tuner worked quite well in Uganda with full wave loops for missionary NVIS comms
when I install some hf systems for WOMF. They were resonant antennas and did not
need a tuner but I wanted them to have the option of going clandestine and using the whole hf band if needed as some of their folks were in Sudan had need to be sneaky at
times. Pretty much install and forget as they take care of mismatches automatically.
It was kinda noisy as far as static crashes go last night so anything that would
have been on the weak side I probably would not have pulled it out.
Being that we are in the solar cycle minimum along with thunderstorm season
it almost becomes a necessity to either have a very efficient antenna system and/or a
big amplifier to enable putting some 'fire to the wire'. I don't have either so that probably
did not help..
I would have been in your dipoles null but with NVIS propagation the directionality is not
as crucial - back to Gooches law. 40m is a bit interesting as a decent daytime band for
local comms with some real dx as it gets dark. Will be nice once the SW broadcasters
exit the band. When there is decent propagation its a mad house with all the broadcasters
sending blow torch signals around the world. 6.955Mhz can be fun to listen to as its the
pirate hangout and one can catch some interesting broadcasts. Have even heard stations
matching frequency with WWV on 10Mhz and transmitting SSB, which meant others with
cheap AM shortwave radios could listen. It was in Spanish so don't know what was up with
that, probably a cartel sending marching orders to the mules on the trail..
I took the hustler 6 band vertical out of the yard (damn coax chewing dogheso perhaps next schedule I will be better able to catch you with more options to rx on.
If you can, get the center of the dipole up as far as you can for more efficiency. Most
folks with an inverted v are NVIS antennas anyways unless they have them up 90' high.