Ham receives ISRO Mars Orbiter

As feeds....


A conventional helix has a diameter of 1/PI waves --that's far less than 1/2 wave (which you claim above)

A fractal helix has a diameter of about 1/8 waves ---that's far less than 1/2 wave (as you claim above)

A loop feed has a diameter of 1/4 wave-- that's far less than 1/2 wave (as you claim above).

I love the basics; I love the frontiers. It's ALL good!

73
Chip W1YW
--------------------------------------------------

"Since the lecture was advertised quoting the 45 million miles( on journey to Mars) Paul has
obtained access to a larger dish at a local amateur radio club and
dramatically increased the distance!!"

 

That IS funny! HEHEHEH!

Well, YOU live in the country with the Reeperbahn;-)

73
Chip W1YW

--------------------------------------------------

"Since the lecture was advertised quoting the 45 million miles( on journey to Mars) Paul has
obtained access to a larger dish at a local amateur radio club and
dramatically increased the distance!!"

 

Once more, with feeling...

In the news, in the know

---------------------------------------------------------------

"Since the lecture was advertised quoting the 45 million miles( on journey to Mars) Paul has
obtained access to a larger dish at a local amateur radio club and
dramatically increased the distance!!"

 

Yep. For moderately large paraboloids. To first order its a very good approximation.

Not for order magnitude wavelength apertures. This is not a small aperture.

Which texts? Probably taught from 'em.

73
Chip W1YW

---------------------------------------------------------------

"Since the lecture was advertised quoting the 45 million miles( on journey to Mars) Paul has
obtained access to a larger dish at a local amateur radio club and
dramatically increased the distance!!"

 

A helix has not only a diameter but also a length, even worse. It also has a reflector, which is always larger than 1/2 wavelength.

Even if the fractal thing works as a dish feed (show me a radiation pattern) it is still far from a point and geometrical optics. It probably has a length and reflector too, fractal of course.

And also the loop feed is in a can that interacts and is larger than 1/2 wavelength.

You have to look at the complete feeder not just parts of it. Nothing is good and you still haven't understood it. You are trying to cheat wherever you can.

 

Edgar,

The only thing you've found wrong here, from me, is a funny typo in spelling 'link'.


73
Chip W1YW

 

If you taught EM textbook knowledge then you yourself have forgotten it. What is an order of magnitude for you? Is 13 cm and 100 cm in the same order of magnitude? I would think so. Dishes smaller than 10 wavelengths are becoming very inefficient and aren't used normally. A 1m dish for S-Band is a very small aperture. You will hardly find smaller aperture dishes in any frequency region. What do you think the wavelength in S-Band is? 13 mm?

 

So, now are these feeders larger than 1/2 wavelength or not? Take a gauge and measure the thing! Or is W1YW right by definition? And how about aperture size? Less than 10 wavelengths is not a small aperture? Come on!

 

http://www.astronomyforum.net/uk-astronomy-forum/56979-m0eyt-iee-lecture-bournemouth-university.html

Item does not refer to ISRO MOM but to NASA mission. Another red herring from Cohen.

 

hmmm...

by Golly!

I have a dish here made from modules with a 3D printer that is about 5 waves in diameter--but the gain is....wait for it!

28 dBi

Goodness!

You are an expert---do the MATH my boy!

Edgar!

Has nature lost its marbles?

IN FACT....it was first funded as a DARPA project--yes one of those nasty ol' baddy waddy AGENCIES we have in the US of A (NOT!!)

Gawd Blessem;-)

According to YOUR perspective this MUST have greater than 100% efficency Edgar!

Edgar, the more you say the less I have fun ribbin you with reality. In fact, at this point you are taking on the veneer of a 'Dish-Punk'.


Go answer KC8VVM questions---if you are able to.

73
Chip W1YW

 

ALWAYS. Man, I love it when people reduce antennas to the level of auto mechanics in a greasy ol garage.. : "The BLANK Always "BLANKS" That's how it is. Stop asking questions and worrying your pretty lil ol head..."

Why does it have to be larger than 1/2 wave? What physics requires that? Be careful now.

Again: WHY DOES A "REFLECTOR HAVE TO BE ALWAYS LARGER THAN 1/2 WAVE"?===DF2MZ

This sounds like 1965 youth ham radio...


73
Chip W1YW

 

I think Chip's gotten into the sauce pretty heavy tonight.

 

LOL Chip, you are a funny guy - when will you make your first appearance on Saturday night live?

You only have to look at the number of W1YW replies to this thread with tangential responses - always trying to steer the reader away from Chip's initial responses where he claims that I could not have possibly received MOM with a 3ft antenna, this does say a lot.

I am sure if Chip put the same amount of effort into correctly analyzing the provided FFT's and re-doing the link budget again, he would become pretty full up after having to eat a huge portion of humble pie.

The bottom line is that Chip has failed to correctly analyze the link budget, and is therefore wrong about the entire scenario, and he'll always be wrong because he is incapable of setting up a receive station to prove to himself that reception is possible, with small antennas, of signals originating from spacecraft orbiting Mars.

I'll post some new FFT's shortly to the Twitter feed showing the MOM S-Band signal - hell I'll even plot the received carrier frequency from my system, and also from the NASA DSN at Madrid for comparison, Chip can then provide his 42 years worth of 'expertise' in trying to persuade world + dog that this is still 'not happening'!

Chip, really OM, I would have thought by now the evidence provided would have made you realize that your position is untenable - you have been proved wrong so please learn from this and move on.

Have a great day,

73's Paul M0EYT.

PS - any further replies Chip, ensure you remain on topic, not flying off on tangents, or quoting totally unrelated items etc. I'm still waiting for your **expert** response to my question on the coincidental carrier that just happens to exhibit the same properties as the MOM S-Band signal - this I have to see ;-) Looking forward to the show.

 

And, as I said--see Post #176-- I would be delighted to respond to a question that quotes the actual statement. Go ahead. There is an obvious answer. Just as the obvious answer that you did not show us data from a 3 foot chicken wire dish. And that you are apparently incapable of showing errors in the link budget.

73
Chip W1YW

--------------------------------------------------

"Since the lecture was advertised quoting the 45 million miles( on journey to Mars) Paul has
obtained access to a larger dish at a local amateur radio club and
dramatically increased the distance!!"

 

Dear Chip of 42 years experience in something or other,

Why don't you re-read the article about my local ham radio clubs antenna - this was used years back for X-Band DSN reception, not S-Band - can you and your 42 years of bloody **experience** not understand this?

The antenna I use on a daily basis for S-band reception, as repeatedly posted on Twitter etc is shown at http://pjm.uhf-satcom.com/twtr/antenna.jpg - Yet again, spelling out for you; 3ft diameter mesh antenna, helix antenna feed, G4DDK VLNA - does this penetrate your thick skull ?

Are you happy to admit that you were wrong with your initial blah-blah and other hot-air saying this is impossible??? Just look back at the thread, the supplied FFT's from myself and other observers etc, if you need help interpreting the FFT's with them explaining in terms suitable for a 5 year old, then perhaps ask?

I and the rest of the readers of this thread are still waiting for your **Amazing** explanation on where the MOM like mystery signal could have originated from - at a guess I would say it came from the MOM orbiter, but thats **impossible** according to you Chip!!!

As a parting comment - why don't you prove to me and the readers of this thread that instead of being a gobby b/s'er, you can put your money where your big mouth is, and build an S-Band receive system for ISRO's MOM spacecraft using a small 3ft diameter dish (Caveat, no cheating with bent paperclips / fractal antennas). If you are not prepared to do this, I would suggest you close your mouth, read the thread and learn to think before you start trolling a valid thread with your poison / other nonsense - you are an embarrassment to this hobby.

I'll accept an apology from you and we'll draw a line under it all - you have been proven wrong, and you insist on going off on tangents to divert readers attention to the fact that you misinterpreted the data and other facts about the receive system.

Maybe you could join the Amateur-DSN group at Yahoo groups, I'm sure we (both hams and professionals at NASA/ESA/etc) could all benefit from your great wealth of experience on these topics (SiC).

Regards,

Paul M0EYT.