WB5N, David Sarkozi

18/07/2024

Built a 2 Element 6 meter yagi from 4 hamsticks. I used a 3/8-24 dipole mount for the hamsticks on the driven element and just mounted the director right to the boom. SWR was about 1.7 and the modem predicted 1.64. No activity on 6 meters to test today but local PSKReporter results seems to show the 6 db front to back predicted

09/07/2024

Rough day to be a ham in Houston, cat 1 hurricane Beryl did a number on my antennas, I have the verticals back vertical and am QRV again. Will get the hex repaired as soon as the ground dries enough to support a ladder. Could have been so much worse.

11/06/2024

Is it a sign?

15/05/2024

Built this 20 meter parasitic array today with 1 single parasitic director. I used only 3 quarter wavelength radials with no radial to the rear, 2 on each element perpendicular to the array and a single one on each element in the direction of the array. The set up was less than 30 minutes and now that I've done it once I bet its less than 15 minutes next time.

The materials where 2 chameleon 16.5 for telescoping whips, 2 3/8-24 mirror mounts, 2 3 foot pieces of 3/8 rebar to support the 3 foot pvc posts and wire for the radials.

I set up the director first and tuned it for 15.56 MHZ with my RigExpert analyzer. The driven element is placed a quarter wavelength behind it as measure with the radial and then tuned for 14.250 MHz. SWR was 1.2 at the target frequency and usable across the band.

Testing on air it seemed like it has the expected half an s-unit or 3dB gain in the desired direction.

09/04/2024

A small gallery of my processed Eclipse 2024 photos from Hot Springs Arkansas. 3 minutes 24 seconds of totality I think.

08/04/2024

06/03/2024

I think I finally found a way to display QSL that on like. Floating picture shelves and post cars protectors

06/12/2023

woo-hoo, I've renewed my Belize license, V31DS for another year!

09/09/2023

A couple of weeks ago I melted a WRC running 400 160m during WwDigi DX. Turns out a WRC is only rated for 20w on digital. Who would have guess lol. I found this ceramic 90 microHenry coil on eBay and made a new 160m antenna today. After 5 minutes of CQing at 225 watts it’s only heated up to 122 F from a no power temp of 115. I’m perfectly comfortable running that power now on 160m

20/08/2023

I’m wanted to get on 80 FT8 tonight but my 75m ham stick won’t tune that low. I suddenly got a bit of inspiration and realized my WRC 9 foot whip would fit the hamstick. It tuned easily to FT8 and I was good to go.

19/08/2023

I did two hit and run activations today, 23 QSO from Fort Davis NHS, K-0816 and 10 QSO from Balmorhea SP, K-2985 both in DM80, west Texas. I added some bands to my N1CC activator totals. At K-0816 I added 30m, 12m, 10m for 7 bands activated and 12m and 10m to K-2985 for 3 bands from that park. 30M surprised me, I worked several station on the east coast at 3 pm local time. At both parks 12m and 10m DX was excellent on FT8. Notable for me was I added D2UY, Angola, as a new DXCC country worked from a park. That was on 10m FT8. He was very strong and worked on the first call. He gave me +08 as my signal report while I was running 25 watts to a hamstick magmount. If you would like to work DX from a park, I highly recommend 12m and 10m FT8. I've worked 13 counties on 88 QSO and I'm not really trying in 24 hours.

18/08/2023

K-0006 Big Bend NP in west Texas 2023-08-17. Only made 16 QSOs on a hit and run just passing through, wouldn’t have done it if it weren’t for my America the Beautiful Pass! It was 106 in the shade, and there was no shade!

18/08/2023

Activated Davis Mountains State Park, K-3003 in west Texas for the late shift on 2023-8-18 from the top of Skyline dr. I started. I made 55 Q's and got to make and eyeball QSO (and on the air) with Scott KI5ZDQ, the park host and fellow POTArian.

18/08/2023

Activated Black Gap WMA, K-6540, in west Texas today for the first time. This park only had 7 previous activations and only 357 Q’s. I made 74 Q’s at this off the beaten path park. It’s located on the east side of Big Bend NP. I saw no one the entire time I was there and only passed one car on the road to the park. It’s very primitive and in fact the restroom at the camp ground is welded shut! No cell service either.

17/06/2023

I think this is my last FD project antenna. It’s a homebrew 10 meter/6 meter hexbeam made from tent poles and a sheet of aluminum from Amazon. It seems to be working. I’ve made a half dozen 10 and 6 meter FT8 qso on it to test. I used 2 feed lines because I might want to be on both bands at the same time. The mast is only 10 feet of doubled up PCV and slips into a piece of PVC attached to a 4 foot piece of rebar pounded into the ground. It folds up to just 24 inches or about 0.6 meters. I can also use it with with a drive on mount. I should be able to deploy it on about 20 minutes.

10/06/2023

My latest experiment. I’ve had this idea for a while for a temporary portable shortened vertical. When I found some 13 inch telescoping antennas on eBay for .99 each I had to try it. The antennas are mounted on a 1 foot piece of aluminum tube. It’s a bit heavy because I end using 0.125 wall tubing. It hangs down about 2 feet from the top and I load the whole thing with a Wolf River Coil. Unloaded a 21 foot vertical should be resonate at 11 MHz or there about. With the capacitance hat collapsed it resonates at 9.5 MHz. With it extended it resonates at at 9.2 MHz. So it lowers the resonance by about 1.8 MHz. If I use all of the WRC it is resonate at 2.280 MHz so it almost makes 160 meters. I should easily be able to load my 31 on 160 meters. It should raise the efficiency of the antenna and I’m going to try it this weekend on 80 meters

29/05/2023

Continuing my exploration of using a 1/4 wave 40m vertical along side a 1/4 15m vertical while for 15 meters the question was asked what do the two verticals do to each other's radiation pattern? Turns out more than I anticpated, although perhaps with some though it could be an advantage. The 3/4 on 15m, i.e. the 1/4 40m has the most effect on the pattern of the 1/4 15m, but with some though on set up perhaps thats something I can exploit. I'm using just 3 radials, but I modeled with 4 radials for each of calcuating in my head wire lengths. These are the models setting up the vertcals 1/4 on 15m apart.

28/05/2023

The antenna on the right is a 1/4 wave 40m vertical and the one on the left is a 1/4 15m vertical. In another post a commenter suggested using the 40m on 15m as a 3/4 wave vertical. Interesting thought. I did some models and I got a takeoff angle of 23 for the 1/4 wave and 60 for the 3/4 wave but a gain figure of 4.6dB. I thought in most cases the 1/4 would perform better than the 3/4 because of the take off angle. Today I compared them size by side on FT8 averaging 3 reading for each station on each antenna. I was surprised by the results. The 3/4 antenna averaged 2.79 dB better on US stations and the 1/4 was 1.77 dB better on average for DX. Since these antennas are for Field Day in rethinking setting up a 1/4 antenna at all. I will likely set it up for FD but suspect the 3/4 might be my go to for FD.

26/05/2023

I just received a new 32 foot fiberglass telescoping pole from The Mast Company. I’m using it to support a full size 1/4 wave 40 meter vertical for field day. I'm feeding it with my WRC with no loading and I'm using 3 1/4 radials "barely elevated" I set it up to do some testing today. I was able to set it up in about 15 minutes. I'm supporting the mast with two PVC couplers clamped to a 4 foot piece of 1/2 inch rebar. I've been comparing it to my 4BTV with 20 buried 16 foot radials this afternoon and its been 2.5-3 db better consitantly than the 4BTV. My test site slopes up to the north a lot and I'm sure that has a negative effect. My field day site will be K-2994, Caddo Lake State Park in Texas. This arragment with the WRC will allow me to use the same antenna on 80 meters and 60 meters by just adjusting the coil. I'm pretty please with this antenna so far and will play with it some this weekend in WPX CW.

14/05/2023

First QSO of the day im the log as V31DS, 20 meters FT4

12/05/2023

24/02/2023

Last weekend was my first time using the MFJ Hex-beam in a contest for ARRL DX CW. It made an amazing difference and I had maybe my best score ever in a solo DX contest (756 QSOs, 292 mults, 662,256 score). This got me thinking what can I do to improve my "pocket contest station". I live on a 90' x 50' lot. I do have access to the 200 foot wide flood control district right-of-way and I've not shy about putting temp antennas in it. So after a week of thinking about it here are some action items to improve things.

1) The MFJ Hex-beam is rotated with a tag line. I know I missed multiplies in ARRL DX because I was slow to run outside to rotate the antenna. I need an actual rotator. Eric Silverthorn, NM5M suggested rotating it from the base. Doing some searches at least SpiderBeams masts have a kit to do this. Doing all of this with a total SpiderBeam solution and a Yasue rotator would cost about $1,000 (Mast, rotator struts, rotator.) I've got some ideas of how to do it with homebrew solution at a lower cost. A Rohn pushup pole is a lot cheaper than a SpiderBeam aluminum mast, a used rotator, perhaps mounted against a post set in concrete for support.

2) 160 meters was a total bust, I never made a single QSO on the band this time from my inverted L loaded with my WRC. My environment is just too noisy here. I think I'm going to build a coax receiving loop. I've already ordered parts.

3) More ompf is needed on 40 meters. I'm thinking a full size 40 meters vertical with elevated radials vs my 4BTV with buried radials. Probably something temp. I'm trying to decided between an aluminum vertical or making a wire on on a fibergrass telescoping mast. The mast could be used for other things too.

I have an amp I need to get in service, a vintage Amp Supply LK500-ZB. More power seems like a smart way to go, but I think I will always be more competitive in the low power categories because more of those in the high power classes will have larger antenna systems.

25/01/2023

Simple adaptor I made today to attach an extended wire to load with my WRC Silver Bullet 1000. Since the 1000 is about 88 micro Henries I can use it to load a 45 foot or longer wire as an inverted L for 160 meters. I support the wire on a 22 foot telescoping fiberglass mast. I will also use the same adaptor for a quarter wave inverted L for 80 meters for Winter FD without any loading

30/10/2022

Less than 12 hours left in CQWW SSB and 15 meters and 10 meters are awake to Europe. Beat last year’s score at the 24 hour mark.

29/10/2022

Hour 13 CQWW SSB

09/09/2022

Hamstick with Elevated Radials

I did an experiment for future POTA activations. I took a truck mirror mount for a 3/8-25 thread antenna and put it on a post and added 3 quarter wave elevated radiala for 20 meters and attached a 20 meter Hamstick. The results are interesting:

The resonance of the Hamstick moved down in frequency. From the SWR graphs you can see it moved from 14.310 MHz on the car's magnetic mount to 13.990 Mhz on the elevated radials.

On the radio the first thing I noticed was about 1 S unit more band noise on the elevated radials compared to my 4BTV with 20 buried 16 foot radials.

Calling CQ on both antennas I compared the results to RBN. The antennas must radiate very differently I could only get reports for both antennas from 2 skimmers. K1TTT had the 4BTV at 5 dB and the Hamstick at 11 dB. WS3W had the 4BTV at 4 dB and the hamstick at 6 dB.

Total investment in this was less the $20 and that included a 250 foot roll of 25 awg silicon wire for radials. I need to keep testing but this does seem to work reasonably well and give me some options for longer POTA activations where I'm not operating from my car. For this cost I could have a couple of these monoband verticals more option and faster band changes with hamsticks.

I need to go somewhere where I could set up the elevated radials and do some testing compared to the magnetic mount.

22/07/2022

Prototype of an all wire and guy line hexbeam I put together as an experiment. The idea is a super light weight low material hexbeam that’s super portable. It is supports on a single fiberglass mast. The center is a 4 inch hex hub a made from marine plastic with a hand saw and drill. The top of the mast goes through the center hole. A short piece of paracord ties it to the eyelet at the top of the mast through the hole marked with an arrow. Guys calculated to 45 degree angles support the mast and the antenna itself. Testing seems to show it has about about 6 db of gain and a close to expected pattern.

I'm trying to decided if I want to continue developing it. It could be an excellent Field Day or POTA antenna for some situations. I seem I have cut this one wrong and its resonate pretty high in the 10 meter band, so much so I should recut the wires. I'd like to remake it with 18 AWG poly-stealth to make it lighter and add some fishing tackle instead of small carbineers to make it lighter.

Problems I had with it is your guys need to be pretty precise and exactly the correct length else the mast bows and the feed point is is in the wrong place. This wouldn't be as big an issue with a less flexible mast.

If you had a really tall tow you could use this idea to build an 80 meter hex beam! I think it would work on a 150 foot tower!

08/07/2022

Just finished a 6 meter Hex-Beam for portable/POTA use. I made my own hub out of plywood, pvc, L-brackets, and 3/8 inch coax clamps. The poles are tent pole replacement kits. The wire spacers are 1/4 inch Teflon rod. The feed point is a Radio Wavz dipole head. Everything can be found at Home Depot/Lowes and amazon and no special tools needed.

SWR was about 1.1:1 at 50.313 so I quit testing, lol. I did spin the beam on a loud local FT8 single and it was S5 pointed at it, S1 off the back and S3 off the side so I'm pretty happy with it.

I used the measurements off of hex-beam.com

the one problem I had is initially I intended to attach the wire to the Teflon using #4 hose clamps that should go down to 1/4 inch, nope they don't so for now its just taped.

This one will likely get permanently mounted at home and rebuilt so the tent poles fold over more compactly.

04/07/2022

Jordon, Country #187