Dual-Band Satellite Dish Slot Antenna - QSO Today Virtual Ham Expo 2021

[@jackfrench3324]

Excellent presentation Marcel. Loved it. 73!

[@_Mordion_]

This was such a well made video and very well thought out experiment. I'm a new ham and have one of these on top of my house from the previous owners. I can't wait to try this.

[@_Mordion_]

One question though. Your results showed that the slot antenna design didn't accomplish the omnidirectional goal. I know the yagi is pretty much the pinnacle of directional antenna designs. Could a slot antenna design such as this fill the same role of a yagi though?

[@MarcelStieber]

Thanks for the kind words! In order to improve the directionality, you'd have to explore additional elements to direct and reflect the signals in the desired direction. Not something I've explored.

[@screamindemon24]

I live in an HOA community. I've been looking for a stealth antenna; glad I came across John's 2 meter design. Someone then linked your video.This comes at a perfect time! Thank you!

[@richlobato8664]

I've been wanting to make one of these but kept putting it off due to lack of detailed information. Thank you for a well produced and detailed explanation.

[@blakepresent]

I just don’t know where to begin. What a great presentation. I learned a lot. I can’t wait to try this on my DIRECTV dish. Thank you again. Blake, KB5RZM.

[@chiphungerford]

This was a very High Quality presentation, great job!!

[@dang25272549]

Thanks for your good info . Such a perfect guideline for me .

[@phillmorgan1589]

Im a little late to the part here but wow. What a great presentation! Luckily Im not in an hoa situation but I still want to make one of these. Great video :) 73

[@ManuelPinner]

You can use these for the 23 Center Meters Band with a Biquad in the place of the LMB,

[@charlesontiveros3879]

Go Mustangs! Nice job, Marcel.

[@ColbyHiggs]

Thank you for posting!

[@Montaguy]

Awesome work. Very helpful.

[@RideGasGas]

Thanks, interesting presentation. Sorry if I missed it, but did you do any gain comparisons with a half wave dipole or other antenna of known gain?

[@MarcelStieber]

Around 12:30 in the video, column E was an X-30 antenna, but I don't trust the absolute numbers that much given the alignment variation for the high-gain vertical antenna. The referenced QST article has the simulation results showing 2.1dBi peak: w6nbc.com/articles/2016-03QSTdishslot.pdf

[@thomasmanson1119]

Great idea Marcel, but I’m curious (and have been since reading John’s original article), but doesn’t the parabolic shape of the antenna dish disrupt the 2m/70cm propagation? Thanks, 73 Tom KC3QAC

[@thomasmanson1119]

I’m goofy! The parabolic shape is only relative to the feed horn and you aren’t using that anyway! Sorry for the interruption. 73 Tom KC3QAC

[@NimblyJimbly]

Super interesting video! Thanks for sharing. I got my license last year and have really been enjoying the hobby so far. One of my favorite parts is seeing all of the different antennas that people design. Would love to see a follow up video testing your suggested improvements/optimizations. Also, what are the chances of cutting a third slot for 1.25m to make this a tri-band antenna?

[@MarcelStieber]

Glad you liked it! A third slot would surely work. Follow the tips around slot placement towards the center of the dish. It's still a compromised antenna to make it stealth, but definitely a fun concept to play with!

[@tommyboy7820]

Thanks for sharing

[@GeorgeMarkward]

Great presentation, thank you for all the details. Have you considered what would happen if 220 and 1.2ghz slots were added to the design?

[@MarcelStieber]

I haven't tried it myself, but the same concepts should work. You'd likely want to do a dedicated feed for the 1.2Ghz and keep it centered on the dish as much as possible.

[@mikemorris5730]

@@MarcelStieber wa6ilq here... I'd like to chime in on this.... Have you thought of doing a V2.0 with repositioned slots, and a quadplexer? (146-220-440-1200), and extending the 2m band down to the 145 MHz repeaters. I'd be willing to toss some $ into a kitty to fund a V2 that would be published with dimensions.

[@MarcelStieber]

@@mikemorris5730 I have not done so. You're welcome to try! The same concepts apply.

[@evanprout3349]

Is this antenna is horizontally polarized? How many DB are lost when transmitting to a vertically polerized antenna?

[@MarcelStieber]

@@evanprout3349 a horizontal slot antenna is vertically polarized. Mismatched polarization can lose 20dB.

[@radioboys8986]

TNX OM dit dit

[@ManuelPinner]

The UHF Slot must be always in the Center,

[@psikic72032]

Is there any chance Ku-band satellite reception via the feedhorn might still work on this dish? It looks like Ku-band has a minimum wavelength of 1.67cm, and so if the slots aren't any wider than that, I would guess that the dish could still properly reflect the signal to the feedhorn.

[@MarcelStieber]

Yes, definitely possible. I removed the Feedhorn cables on this one, but I know some others have tried making it multipurpose. Maintaining the shape of the dish might be the hardest part.

[@renzoids]

What happens if you add a small yogi in the center in the place of the feed arm as the 2 meter and leaving the slot for 70 cm? Could it work out?

[@MarcelStieber]

Sure? The Yagi will interact with the dish, so you'd need to be a bit careful with the design. Also, a 2m Yagi would be quite large and might look strange in the dish.

[@pcmann2004]

Does the LNB have any effect on the antenna?

[@MarcelStieber]

Yes, see around 14:21 in the video.

[@Tom_Rad]

Would this work with a mesh dish antenna rather than solid metal dish?

[@MarcelStieber]

Possibly? Depends on how the slot is cut and how the current can flow around it through the mesh. Try it out!

[@leons4571]

So , here is a question / idea -- If you replace the metal arm in front the dish with an insulated arm and addon yagi directors , do you think it can add some gain and a little more directivity ????? de 9Z4BM

[@MarcelStieber]

Sure

[@cherylholder930]

I have a 6ft oval fiberglass dish….would it work

[@MarcelStieber]

If it's fiberglass, then a traditional slot antenna wouldn't work since it's not conductive.

[@BrendaEM]

The slot could be hidden and strengthened by fiberglassing over the cut. The area where it's added would have to be taken down to bare metal. Getting some waterproof resin and some Veil (thin) fiberglass from Tap plastic. Add a layer or two on each side. Afterwords, the fiberglass could be sanded, and painted. The slot likely would not show much at all, and it would be sealed from rust. Cool idea for HOA's. The FCC needs to step up, and step in, against HOAs.

[@MarcelStieber]

Take a look at one of the references. One of them tried that and had major changes to the SWR. You'd need to account for the filer material and adjust the slot design according.

[@dpsflyboy]

Question I had, when you changed the length of the VHF slot, did you change the feedpoint location also? Thanks for the presentation.

[@MarcelStieber]

I extended both ends of the slot a bit, so it inherently moved the feedpoint a bit. The specific feedpoint isn't that critical in my experience.