Hi All
I've had to move my setup and now have no access to putting up an external antenna for my mode S receivers. This means that I'm stuck with the indoor antennas that shipped with the units originally.
My question is, are there any indoor antennas which will give better reception than the supplied indoor ones? Specifically, I had the BSBW-1090 Window Antenna in mind.
Stephen
Hi Stephen,
I haven't used the BSBW-1090 antenna, but I've been impressed with antennas supplied by Kinetic. I've got an SBS-3 in my study and a Beast which I use for mobile work with the whip antenna supplied with the SBS-3.
This whip antenna, mounted on a small frying pan on the inside window sill of my dining room (30 mtrs ASL), is giving me a max range of 248nm for aircraft between FL310 and FL390 today (weak to fair tropo ducting). That's comparable to my SBS-3 with 0db gain antenna mounted on the chimney.
Tom
Hi Stephen. I followed Toms suggestion about the ground plane idea It works a treat. Infact I've cut another ali 12ins dia disk out.Its going on the external antenna.
An Tom I know we get lift on 2mtrs .What about UHF?
Regards billko
Hi billko,
Yes indeed, lift applies to UHF and to SHF as well. Have a look here for the forecast ducting.
http://www.dxinfocentre.com/tropo_nwe.html
Tom
Hi Tom. Thanks for the site. A very strange day Friday! on UHF. Got a problem on top band,3000ish khz.5000ish khz with QRN .Down to external psu for sbs-3.You or Mike any suggestions??
Billko
Quote from: viking9 on March 10, 2012, 12:18:41 PM
Hi Stephen,
I haven't used the BSBW-1090 antenna, but I've been impressed with antennas supplied by Kinetic. I've got an SBS-3 in my study and a Beast which I use for mobile work with the whip antenna supplied with the SBS-3.
This whip antenna, mounted on a small frying pan on the inside window sill of my dining room (30 mtrs ASL), is giving me a max range of 248nm for aircraft between FL310 and FL390 today (weak to fair tropo ducting). That's comparable to my SBS-3 with 0db gain antenna mounted on the chimney.
Tom
Thanks Tom and Billko
Am I right in thinking that the sbs-3 antenna is the AS-1105 high-gain whip?
I never thought about using a frying pan as a metal ground plane. I read elsewhere that 4 to 5 inches was the optimum size for one, but you reckon that a 10 to 12 inches metal ground plane gives better results?
I'm now stuck with a window sill and so I'm very limited on the size of an antenna setup I can place there. Also I don't want to spend a small fortune on an indoor antenna setup only to find it's only marginally better than the supplied kit. However, a cheap supermarket frying pan and a ~£25 whip antenna sounds a great setup on a budget.
Stephen
Hi Stephen . Please don't take my ground plane size as the correct one. Tom did'nt suggest any size.. The measurements I got was from a Avionics site I will look in my bookmarks and post you the site
Billko
Hi Again Stephen. try this site http://www.cumulus-soaring.com/antennas.htm
Does a ground plane have to be flat or could it have 90o angles??
Quote from: Smudger98 on March 10, 2012, 02:33:37 PM
Does a ground plane have to be flat or could it have 90o angles??
Sorry I didn't get back earlier guys. WCR on the tele followed by the first lawn mow of the year! The minimum ground plane diameter for 1090 MHz is quite small. The one AirNav supply is around 4" diameter. I use a frying pan as that is what I had handy for testing indoors. I used the lid of a Quality Street tin with a whip out doors for a year with good result. Cheaper than a frying pan and you can eat the contents, unless you are diabetic like me. ;D
Quote from: Smudger98 on March 10, 2012, 02:33:37 PM
Does a ground plane have to be flat or could it have 90o angles??
Only MonoPole Omnidirectional Verticals need (artifical ground plane) to function
because originally they were based on a dipole scheme with the lower element amputated
(from MF/HF towers against Ground Soil)
With VHF and higher that developed into an artificial ground pane of some sort and these
are flat horizontal whether a real metal pane of some sort or number of radials.
e.g. mobile car roof or hood, or stationary on top of mast raised into height.
To my knowledge the only exception is a shipborne VHF tilted by 45deg with only 1/2 semicircular pane
as lower half, reason they want to catch BOTH vertical AND horizontal oriented transmissions likewise.
Usually they are in pairs at opposite crosstrees.
No 90deg bends or angles.
However if you think of a large oil can cut out with a higher rim for stability
that sure would no harm - think of the raising windload on thin masts
And BTW other Ant Systems like with multiple stacked elements,
coaxial sleeve ant(dipol),
Triple leg(dipol with 60deg sloped radials) or 4 radials 45degs sloped
they all DO NOT need a Ground Plane and can be placed on-top of mast.
Thanks Klaus.. I have a square biscuit tin lid that i thought of folding into 3 to slot over a window ledge..
Of course a car roof makes a super ground plane but my wife won't let me have it in the dining room. ;)
;D ;D ;D
Quote from: Smudger98 on March 11, 2012, 10:43:21 AM
Thanks Klaus.. I have a square biscuit tin lid that i thought of folding into 3 to slot over a window ledge..
Almost anything goes...
unlike the sloped radials which dims are cut to freq,
you may use any metal sheet on hand
provided you see that nothing is distorting your desired pane,
any small rim upwards is no harm , considering that 1/4 wavelength is only ~ 7cms
Hi Smudger In my chicken box days the best ground plane for the k40 was the greenhouse
Billko
Well Klaus . We can kick this topic around till the cows come home .The discone Has its tx In the form of a flat disk.On the top
The antenna on Tec-net has a 113mm ground plane. I built one a couple of weeks back it performed better then the mag- mount in the same location.The VHF antenna is a new 1 on me.The ones we used were the vertical type . the HF ones were zepps Types if my memory serves me well. Then that was 50 years ago when I was in the merchant navy. The whole ship was our ground plane along with the salt water.
Regards Billko
I've posted this elsewhere on this forum, but now having used the PCB antenna, I can say it's very good and I recommend it. It's available in indoor and outdoor versions too.
Quote from: Bethsalem on January 07, 2013, 05:57:15 PM
I've posted this elsewhere on this forum, but now having used the PCB antenna, I can say it's very good and I recommend it. It's available in indoor and outdoor versions too.
Hi, what is the max distance it can receive? And could you supply a photo about what it looks like?
It will be very helpful if you have a detailed blueprint.
Thanks a lot!
Hi Stargate
I bought the antenna from Francois over on the Beast forum. Unfortunately he's no longer making them, but he might start again in the future. Have a look here for the info you're after.
http://groups.yahoo.com/group/ModeSBeast/message/1181
Stephen
Quote from: Bethsalem on February 16, 2013, 07:58:37 PM
Hi Stargate
I bought the antenna from Francois over on the Beast forum. Unfortunately he's no longer making them, but he might start again in the future. Have a look here for the info you're after.
http://groups.yahoo.com/group/ModeSBeast/message/1181
Stephen
Thank you very much Stephen. But I can't see the pics even joined the group and went into the Photo folder.
That group isn't storing the "attachments" on the group. aka "Email attachments are distributed, not archived"
It's using this setting: "Include in emails (exclude from site)"
That group could use this setting "Store on site (exclude from emails)".
Stargate
If you sign into the Beast forum and then look at the left hand screen menu, you'll see "photos", the ones you want should be there.
Stephen
Or just look here on his own web site
http://f5ann.pagesperso-orange.fr/AntennePCB-1090MHz/index.html
Quote from: IanH on February 17, 2013, 07:22:38 PM
Or just look here on his own web site
http://f5ann.pagesperso-orange.fr/AntennePCB-1090MHz/index.html
Thank you very much. I saw it finally.