Enthusiastic Steve: Slim Jim Is it really any good?
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- เผยแพร่เมื่อ 28 มิ.ย. 2024
- Hello from Enthusiastic Steve, in this video I will be building and testing on air an antenna that many of you have been telling me is a fantastic antenna, better than a 5/8th wave better than a 3/4 wave and scalable to most bands.
What is this amazing antenna?
Well its a design that's been around for nearly a 100 years, the "Slim Jim" Antenna.
Simple, cost effective to make and a great performer, or so you tell me?????
Lets build one, try it on air from home base then take it out up a hill top for greater range.
Thank you for watching, please consider subscribing to my TH-cam channel, it helps with my viewing figures and to build my channel. Content takes many hours to put together so i appreciate every single view and look forward to any comments.
Thank you to all who helped me by coming back to my calls on air so I could do the comparisons.
Many thanks
73s Enthusiastic Steve - วิทยาศาสตร์และเทคโนโลยี
As a newly licenced 14 yr old back in 1978 I bought a Slim Jim at the Ally Pally show. My Dad kindly scaled the house in Charlton SE London and stuck it on the roof at about 45ft. No balun or loops needed to get 1:1 on 2m... it was fantastic! Worked so well on FM and SSB, I often forgot to switch over to my 6 ele quad yet worked as far as east germany and the south of france on 10w [was a great time for sunspots lol] Keen to get reactivated now, you have inspired me thank you! I love fiddling around with wacky antenna ideas ;-D 73s G8RXW
Thats brilliant 👍, thank you for your comment regards Steve
Very interesting Steve, glad you had fun testing your SlimJim. One point I will make. The switcher box you are using is very lossy at 70MHz They wern't that good on 27MHz their design frequency.
One thing I discovered years ago on 145 MHz is that there is an actual null in the radiation pattern of the slimjim, so when out portable again try turning the slimjim by 90 degs and see the results. Definitely worth experimenting Steve. 73 Mark G0NMY
I used a commercial Slim Jim that I had renovated for 2 Meters in 2003 when I was first licenced. It did what it said on the tin and I couldn't fault it. I only took it down after being donated a dual band collinear which had a little bit more gain. I also like the fact that the Slim Jim is DC grounded - never a bad thing!
Thanx, interesting, never knew THIS much abt the antenna! 73 de WA4ELW in TN 🇺🇸😀
Yep, the slim jim is a very good antenna Steve. I built my first one in about 1979 for the 11Mtr CB band. It was rough and Heath Robinson would have been well impressed :-). Over the years I've made them for 6M, 2M, 70Cms, and 4 Mtrs. Never a disapointment. As you say, that lower angle of radiation makes a lot of difference. I currently use a J pole on 4Mtrs. Home brew converted fron a CB end fed 1/2 wave. No complaints. You mentioned the colinear J pole. I've made them for the above bands except CB...really too big. I've just built one for 4Mtrs and I'm waiting for a dry, windless day to pop it up. It's also cable tied to a 7Mtr fibreglass pole. 73 Moss G1IML
When u were first talking to the very first station, irregardless of signal strength, I cud HEAR him much better on the Slim Jim!
I've made slim jim dipole last year for 4m it works fantastic then I've made J pole it was even better definitely recommend it.
Read W8JIs comments on the slim Jim antenna,
He probably one of the greatest minds in HF /VHF antenna design.
He’s not a fan of this type of antenna because of dealing with the considerable CMI that even a choke cannot completely cure.
If you are going to go vertical then try a Straight vertical dipole with the 50 ohm coax going away from the angle at a right angle..
73
Mark
Great video Steve , I must make one of these for 4m , I recently a few weeks ago set up a quarterwave Sirio that I was given ,seemed to work good , worked a few stations on the Sunday morning fm net one in Winchester and could hear one of the stations you worked on this video on the Isle of Wight but unfortunately his noise level was high at the time , I must get back on 4m , 73 de 2e0nbk in Reading
Hello Nigel, you will find a slim jim or a 5/8th will both out perform a 1/4 wave, i have a sirio 1/4 wave here, it was up one day, great for closer contacts but those of 25 miles away i could no longer hear, on 4m generally height is might, so if you can get an antenna up high thats better. I also use a fibreglass spider beam antenna with a hawkings 5/8th antenna, light weight and i can put it up to 40ft for a net then take it down when done so i don't up set yhe neighbours. Good luck, thank you for your comments. Regards Steve
That’s a great idea with the dipole centre for the feed line 👍🏼
I built one for civil air monitoring and used one of those BNC connectors with two binding posts. I’m impressed with its reception considering the outlay, it doesn’t like any movement though and lives in the loft most of the time. Seems less noisy than a dipole but perhaps not as broadbanded.
73 Franco
Kinda wish we had access to 4Meter here in the states
It may come one day, countries are slowly adopting it as other users move away from the band. Thank you for your comment, regards Steve
That bit at the start, not one bit cringy. Huh! 😅
Me cringy 😂 glad you liked it lol. Regards Steve
Good video Steve! I've made a couple for 2 and 70 with good results. Your ladder line looks wider than what I used and the cores look solid. What cable did you use? Cheers Paul 2E0IES
Hi Paul, it was standard 450 ohm ladder line, you can use the narrower type 300 ohm? But this can get a little twisty. The 450 ohm does work well, especially on the 4m band giving a good match across the whole band. Regards Steve
Thanks Steve a great video . I have a couple of questions first your test SJ v 5/8 at home were the aerials at similar hight?
I have a 10m ground plane on a 12 m spiderbeam at the top with 2 ground planes. Workes pretty well . Do you think this SJ would transfer onto a 12 metre poll on 28.060mhz ? My aim is to improve local contacts at 30 miles, hight is might so the feed point on my 1/4 gp is about 32feet the feed point on the SJ would be about 20-25 feet . What do you think ?
Hi, yes i agree its not the best 2 way switch, but even when not in line their is no noticable difference in signal strength though i except their is some loss. Both antennas were at the same height approx 20ft apart so hopefully no interference one another. The thing with antennas they can give odd results, i would think the sj would work well up your pole but you would have to try it to see as terrain, buildings etc could sway whats expected. Good luck and thank you for the comment. Regards Steve
Another snake oil antenna / dummy load... I bet it works great on 160 HA! Slim Jim indeed! You're better off loading up a beef jerky!
Would have to be big for 160m, but if you did make one it would perform very well 😁👍now you got me wanting some beef jerky lol. Thanks for the comment. Regards Steve
It's a Zepp.
Yes i would say it is, but when i mentioned that locally i got told its a slim jim...... 😁
Hey steve... is that a CB radio and a radio shack wattmeter in your shack?... and it's "73" not "73's" ...good buddy... ugh
Hi, i got a Team, a Nissei, a Midlands, a Hansen and a Micronta power/modulation/swr triple meter tester. The Team one does modulation as well as power and swr. 👍
Big claim. Ha ha ha ha ha ha, what do people say. Comments from social media? Ha ha ha ha