pretty much got the VHF ant. good now on to an HF one...few questions

I am quite pleased with my 1st antenna build (VHF 1/4 wave ground plane) now I want to try an HF long wire type. I have my VHF ant. up about 35 feet on a home made metal conduit/pvc type mast on my apt 2nd floor balcony (not a lot of room to work with) the HF might be a lil more challenging as they tend to be much longer!! I do have a tree close and I might be able to feed some fishing line and sinker up over that and pull the wire up into the tree top? As so that kind of antenna and what to build it out of and the issue of a balun are my main questions. I have done some research on the web and youtube and most seem to be fairly simple vertical wires or horz. dipole types dropped into an inverted V With my space limitations the vertical type might be the best set up for me. Some say just 18 gage or so braided seeker wire can be used? cut to the correct length for a half or quarter wave. My target for now at least is the HF air band (I would love to be able to pick up some of the north Atlantic HF over water aircraft transmissions (from central Indiana) if that's even likely with this type of set up using an RTL/SDR dongel. And as far as a balen goes I am mostly clueless at this point still doing some research on that. what do you all recomond?

thanks Brandon

I am useing the ham it up up converter to get into the HF area with the RTL/SDR dongel

ok I got the wire cut and ready to string it up vertically... should I just use coax (rg-6) as a feed line from the end of the element wire and grounds to the receiver (about 15-20 feet)

This probably should be moved to the HF Receive antenna forum...

Let's step back just a little here. There is no one 'HF air band'. Thee are several segments of the HF utility band where these types of transmissions can be heard. So you need something that's a bit better than a 20 foot piece of wire - however given the lack of much front-end protection on these dongles, we don't want to go too long, otherwise you risk overloading the radio.

Because of where you are, you could probably get away with 40-45 foot of wire - the PAR end fed would, I think, be almost ideal for you, if you have the space to mount it. All you would then need would be an adapter from the end of your coax to the dongle's SMA connector. This is one time I would recommend a little jumper - putting heavy RG6 coax directly on those little SMA connectors is not going to end well at some point. One end of the pigtail would be a SO-239 to accept your coax - the other would be a male SMA connector.

Another similar solution would be to buy the little balun that's recently been mentioned on the RTL-SDR website...

rtl-sdr.com - Page 4 of 50 - RTL-SDR (RTL2832U) and software defined radio news and projects. Also featuring Airspy, HackRF, FCD and more.

As for the jumpers - here's a page with a good sample of them, including the description I gave earlier

Coaxial Cable, Coax Cable Preassembled

Just remember, don't put too much antenna on these little dongles...Mike

Thread moved to HF Antenna forum.

ok thanks mike!!!! ill look into the balun. Still not sure 100% what a balun does and why you need one more on HF then VHF/UHF? I kinda got impatient and wen ahead and hooked up the wire, I only have enough vert space for about 20-22 feet of wire, I found a page on the web discussing random wire antennas for HF and some lengths NOT to used based on wave multiplies of many of the most common HF bands. SO I ended up with about a 21 foot wire strung vertically (about 13 feet off the ground 2nd floor) and then grounded with some horz. wires (about 8 feet long to the left and right of the vert wire) connected directly to about 14 feet of rg-6 coax and that into the coax-sma adaptor into the ham it up rf in. I dono how well its really working yet but I did pick up someone transmitting from Denver he mentioned on 14,208,310 pretty well and a ASOS weather broadcast on 15,034,460 form Trenton Canada (470 NM from Indianapolis) VERY well... I am a little confused on the LSB USB or DSB setting just been trying most of them I got the ASOS transmission best on DSB and the others on USB

ka3jjz said:

This probably should be moved to the HF Receive antenna forum...

Let's step back just a little here. There is no one 'HF air band'. Thee are several segments of the HF utility band where these types of transmissions can be heard.

Click to expand...

I ment air band as aircraft Gander, shanwick, and santa maria control the north atlantic thats the area i was orginal aiming for is i can do this with my limitded space and location in centeral indiana

The sites you mentioned have different sets of frequencies, depending on the family. Notice that they don't reside in a single band - unlike scanning, where aircraft transmissions can be heard in 2 different bands (I'm including milcom in this generalization). Take a look at this article from our wiki

MWARA - The RadioReference Wiki

What frequencies you would want to listen to would depend on the time of day or evening (and what freqs the controllers choose to use during that period), but given good propagation, it's certainly doable.

As for what a balun actually does - well the page I referenced has a rather basic, but generally accurate, description. There's also some anti-static protection on the unit - certainly valuable when static electricity is in the air. The article is about 2/3 of the way down the page. Mike

CAR-A (New York ARINC): 8.846
CAR-A (New York ARINC): 5.550
CAR-A (New York ARINC): 6.577
CAR-A (New York ARINC): 3.455
CAR-A (New York ARINC): 11.396
CAR-A (New York ARINC): 2.887
NAT-A (0800-2200Z): 13.306
NAT-A (2200-0800Z): 5.598
NAT-F (0900-2200Z, Gander Radio): 8.831
NAT-F (2200-0900Z, Gander Radio): 6.622
NAT-B (1000-2100Z): 8.864
NAT-B (2100-1000Z): 5.616
NAT-D : 8.891
NAT-D : 4.675
NAT-D : 11.279
CAR-B (New York ARINC): 6.586
NAT-D (1000-2300Z): 11.279
NAT-J (2300-1000Z): 6.547
CAR-A (New York ARINC): 8.918
ARINC LDOC (Long Distance Operations Control): 6.640
ARINC LDOC (Long Distance Operations Control): 8.933
New York VOLMET: 6.604
HF CAR-B 8846: 8.846
HF NAT-F 8831: 8.831
HF NAT-B 8864: 8.864


any of those would be nice to hear so i am looking at just under 3 mhz up to about a little over 13 mhz

We have mostly all of those - and more - in the link that I supplied -- and yes, it's possible to hear them, assuming you tune in at the right time of day or night, and on a frequency that they are using.

It's more than a little OT here, but you need to become familiar with how propagation works on the HF bands. We have links in our wiki for this, but this one is quite good, as it's fairly basic and gives you a good idea of what you need to consider...(note that links are always blue). A good general rule - there are exceptions - is to stay below 10 Mhz during the evening, above it during the day. You will learn the reason why here....

Propagation Primer - Flash Movie by AE4RV

You will need to use the Flash player for this site...now, back to the subject of antennas....Mike

Just to clarify - if you do get the little 9:1 balun, the jumper you will need will, of course, change - you will need one with a PL-259 plug on one end (to mate with the SO-239 on the balun) to a male SMA connector (to mate with the converter)

While the Universal radio page I gave has them, you might also find them on Amazon/fleaBay. Mike

There was a study on HF propagation done by the navy some years ago the concluded that a simple 9 foot whip antenna could pull in usable levels of signal as low a 2 mhz.

Got a source / link for that, Jerry? Mike

I had the paper copy in my filing cabinet which no longer exist. My google-fu seems to be weak at this point. I'll ask at breakfast in the morning if any of the MARS may still have a copy.

vertical vs horz long wire HF antenna and multi band types.... right now i have a vert oreantded one and i am picking up some aircraft over the western atlantic but the signal are VERY VERY week i can hear the controler fairly well so i can reach out as far as the coastline at least. would a horx one do better? maybe a horz multi banded type like this?

Build a Multiband Shortwave Antenna - Simple Shortwave Antennas for Shortwave Radios!

I use a "off-centre-fed-dipole" (google for OCFD), 30 feet one side, 15 feet the other with a 3:1 ratio (9:1 impedance) transformer at the joint, RG59 to receivers. Worldwide reception. Homebrew transformer from here...

www.dxing.info/equipment/impedance_transformer_bryant2.doc

You don't want a 'tuned' antenna, say a dipole, because you want to receive all HF frequencies, not just ham bands. An OCFD is a broad band untuned antenna and can be made any size as long as one side is double the other in length. It can be made to have a 50ohm impedance at the ham band frequencies but for receiving it doesn't matter. Just don't make it any shorter than mine as performance falls off for the BC band.

brandonoh777 said:

vertical vs horz long wire HF antenna and multi band types.... right now i have a vert oreantded one and i am picking up some aircraft over the western atlantic but the signal are VERY VERY week i can hear the controler fairly well so i can reach out as far as the coastline at least. would a horx one do better? maybe a horz multi banded type like this?

Build a Multiband Shortwave Antenna - Simple Shortwave Antennas for Shortwave Radios!

Click to expand...

While that would be one answer (certainly not the only one), let's ask a few questions here...

a. I'm not up on the SDR software side, so someone can jump in here and advise, that's all the better - but is there some sort of a gain control? If there is you should be nearly at maximum, unless conditions warrant otherwise. Are you using SDR#, etc.?

b. When are you listening (day or night)? That makes a huge difference - the sun - or lack of it - will determine which frequencies you should be checking

c. What frequencies are you hearing traffic on? At what time of the day (night)? As we are in Winter right now, check below 10 Mhz at night, above this during the day (up to about 15-17 Mhz)

d. How are you connecting your antenna to the HF converter? If memory serves, most of these little sticks have SMA connectors on them. Are you certain you are making a good connection? One simple test would be to try to hear WWV; 10 Mhz is a good place to start as it's going to be audible even in the day (at night, it will be fine for several hours after sunset). At night can you hear the 5 Mhz outlet? During the day, can you hear 15 Mhz?

As majoco has ably shown, you really don't need to get fancy - many do - but keep in mind that these little stick SDRs can be overloaded pretty easily, so we don't want to go too crazy....Mike

i am useing sdr console It's all about the software... It's all about the software... It's all about the software... It's all about the software... It's all about the software... but i also have sdr# and HD radio and have tried out a few others though sdr console seem to have quite a few options!! and yes there is gain control(s) softwear and hardware i think.. still learning the softwear and hardware a bit.

some day some night but i know the lower freqs work better at night and higher day (i have noticed NY radio uses freqs usually in the low teens day and singles at night (mhz) 13.297 and 8.906 i have heard some on

i conected center coax to the wire...the shield to several grounded wires (groud radials but not directly to the ground) im on the 2nd floor grounded it to the railing as well no balun...then about 10 feet of rg-6 to a coax-sma adaptor...then into the up convertor..then out of the up convertor via a sma-mcx adaptor to the dongl

I am a pilot as my main job so i've got loads of experience with VHF and some UHF but the HF is the most intriguing to me cause its all new to me so i welcome all of the kondlage i can gain on HF here!! one other big question i have is which demodulation? USB vs LSB DSB? i hear a general rule is below 10 mhz lsb and usb above it? wonder if that applys to the over atlantic aircraft comunications as well? thanks again u guys your great learning new things every day

Hams are the only people who stick to LSB below 9MHz and USB above as it was a way of generating SSB with cheap 9Mhz filters in the early days. All HF Aero is USB. Volmet, MWARA, RDARA, HFDL, LDOC - all USB.
For every civilian HF Aero frequency (and I mean every!) go here...

The Btown Monitoring Post: International Aeronautical HF Frequency List

and for the rest, go here....

Milcom Monitoring Post

I split these up by mistake, so let me clear this up a bit...

brandonoh777 said:

great links!!! thanks again!!!! now i just have to figure out what freq and when....but im getting it slowly... as to the issues of an HF amp and a balun... and vert vs hoz wires? do i need an amp and or balun? and could i have both a vert and horz wires conectded togeather?

Click to expand...

ka3jjz said:

There are times when a balun (or a 9:1 transformer, sometimes referred to as a 'Magnetic Longwire Balun') can be quite useful; there are some antenna designs that require it, others not, but would work better with them.

Amps can be problematic - broadbanded ones can cause more noise and overloading issues than they're worth - however preselectors can be very useful in certain situations. But given that you are using a RTL SDR, I'd avoid that option for the moment.

Just to get started, we have 2 pages in our wiki (links are always blue) with LOTS of information on the subject...

HF Antennas - The RadioReference Wiki

Loops - The RadioReference Wiki

Click to expand...

ka3jjz said:

c. What frequencies are you hearing traffic on? At what time of the day (night)? As we are in Winter right now, check below 10 Mhz at night, above this during the day (up to about 15-17 Mhz)

Click to expand...

i can get 10 mhz right now (about 615pm almost sunset) not so much on 5 mhz 15 mhz comes in pretty good about the same as 10 mhz stupid question but thease are time freqs right u hear like a clock ticking?