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Author Topic: Review Sirio Antenna SD2000N Discone antenna  (Read 2003 times)

Offline ChrisSmolinski

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Review Sirio Antenna SD2000N Discone antenna
« on: May 29, 2018, 2325 UTC »
I finally replaced my old Radio Shack discone (20+ years old) as it was missing several elements. After searching around and looking at reviews, I decided to get this discone from Sirio, which happens to be an Italian company. It's a bit more (OK twice the price) than the cheapie no name discones, but comparable in price to some of the other name brands.  It's very well made, and assembles the same as other discones, insert the 8 sloped elements (which are held in place via set screws), screw in the 8 horizontal elements and the top whip.

This version has an N connector, I use RG-6 TV coax for my runs, so I installed an N to F connector at the antenna, inside the sleeve. Much like my ADS-B antenna, I have this one in a tree, hanging from a tall branch. So it is much higher than my previous discone which was on the side of the house. Another bonus of being further from the house is less QRM/RFI pickup.

I've just been playing with it for about an hour, but am already happy with it, I went from 2 to 7 NOAA weather radio stations on 162 MHz, for example. Still more testing to do, but it's definitely a decent antenna for the price.

Amazon page: https://www.amazon.com/gp/product/B008899J8Y/ref=oh_aui_detailpage_o00_s00?tag=blackcatsyste-20

Next step might be a pre-amp at the antenna. Any suggestions for something that won't cause images/intermod/etc?



Chris Smolinski
Westminster, MD
eQSLs appreciated! csmolinski@blackcatsystems.com
NRD 545 / netSDR / AFE822x / AirSpy HF+ / KiwiSDR / 670 ft horizontal loop / 500 ft northeast beverage / 58 ft T2FD / 300 ft south beverage / 43m / 20m / 10m  dipoles / Crossed Parallel Loop

Offline Pigmeat

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Re: Review Sirio Antenna SD2000N Discone antenna
« Reply #1 on: May 29, 2018, 2352 UTC »
I've heard good things about them, but being a "roll your own" type w/ antennas, paying more than a quarter for one would probably cause me to have a stroke.

Offline ThaDood

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Re: Review Sirio Antenna SD2000N Discone antenna
« Reply #2 on: May 30, 2018, 1729 UTC »
Thus far, I've used two brands of Discones over the last 30-some years, the 1st being the Radio Shack one from the 1980's. That worked very well on VHF high and UHF, and was my 1st dual band antenna for 2M / 440MHz. Terrible on VHF low band, but that was to be expected. I had that one over 30ft in a large fur tree, and the aluminum GND radials broke off of that one during +80MPH storms. A decade ago I bought the $100.00 Diamond Discone, with tunable 6M VERT stinger. I'm using that for 2M, MURS, 222MHz, 440MHz, but wouldn't match 462/467MHz GMRS. Also, 6M FM 52.525MHz. Again, about 30ft up on masts. (This time.) I'm in the bottom of a river valley, and that just less that unity gain helps to get me out of this valley. Anything higher gain just bounces back at me off the hills. (And yes, I've tried it and proven this to myself.) The Diamond also survives +70MHP storms and those stainless steel GND radials seem to hold up well. So, it sounds like that you can't go wrong with the Sirio discone. As far as a preamp? TV amps may be wide band enough for ya, and some have switchable FM traps. As far as not RX'ing IMD? How close are you to pagers, TV stations, and EMS / fire / police dispatch? So far, no IMD for me being only 1 mile from a 1MW UHF DTV transmitter here, but I do get some UHF pager bleed through. So does a friend of mine a few miles away. 


 
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Offline ChrisSmolinski

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Re: Review Sirio Antenna SD2000N Discone antenna
« Reply #3 on: May 30, 2018, 1744 UTC »
Thanks for the suggestions on preamps - I am using a TV amp now in fact, a combo amp and splitter here in the shack (as I had it handy). I do have a a mast mounted Winegard amp somewhere in my boxes of RF parts, when I dig it out I can try installing it at the antenna and see how that works.

I am several miles away from the nearest VHF/UHF transmitter of any significant power, the closest thing is a cell tower about a mile or two away. No FM transmitters for many miles.

I've listened for some GMRS/FRS activity but have not heard any. I recall hearing some years ago during hunting season. I did hear some repeaters on 70 cm for the first time ever I think. ACARS reception is also quite good, and I did hear the ham satellite an hour or so ago, reminds me, another pass coming up.
Chris Smolinski
Westminster, MD
eQSLs appreciated! csmolinski@blackcatsystems.com
NRD 545 / netSDR / AFE822x / AirSpy HF+ / KiwiSDR / 670 ft horizontal loop / 500 ft northeast beverage / 58 ft T2FD / 300 ft south beverage / 43m / 20m / 10m  dipoles / Crossed Parallel Loop

Offline Josh

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Re: Review Sirio Antenna SD2000N Discone antenna
« Reply #4 on: May 30, 2018, 1818 UTC »
I'm tempted to cannibalise my triband HAM 6m/2m/70cm mobile vertical atop my disconey.

So far, the tribander has been a stellar scanner antenna just sitting in the window, getting it up 15 more feet and part of a disconey should make for an even better rf sponge.
Conveniently located near Vincennes Indiana.

Offline ChrisSmolinski

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Re: Review Sirio Antenna SD2000N Discone antenna
« Reply #5 on: May 30, 2018, 1853 UTC »
I'm tempted to cannibalise my triband HAM 6m/2m/70cm mobile vertical atop my disconey.

So far, the tribander has been a stellar scanner antenna just sitting in the window, getting it up 15 more feet and part of a disconey should make for an even better rf sponge.

Agreed, height is everything at these frequencies. So Josh, you're the UHF Mil Air guru - what can I hear at my QTH here in MD? Got any frequencies to recommend?
Chris Smolinski
Westminster, MD
eQSLs appreciated! csmolinski@blackcatsystems.com
NRD 545 / netSDR / AFE822x / AirSpy HF+ / KiwiSDR / 670 ft horizontal loop / 500 ft northeast beverage / 58 ft T2FD / 300 ft south beverage / 43m / 20m / 10m  dipoles / Crossed Parallel Loop

Offline sat_dxer

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Re: Review Sirio Antenna SD2000N Discone antenna
« Reply #6 on: May 31, 2018, 1848 UTC »
Interesting it's not cut for low-band VHF...
Most times & frequencies posted are only an approximation.
Due to adulteration of the E.N.I.G.M.A. "designators" by others and not a match in the Conet Project they are never used.
-30-

Offline Josh

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Re: Review Sirio Antenna SD2000N Discone antenna
« Reply #7 on: May 31, 2018, 2031 UTC »
I'm tempted to cannibalise my triband HAM 6m/2m/70cm mobile vertical atop my disconey.

So far, the tribander has been a stellar scanner antenna just sitting in the window, getting it up 15 more feet and part of a disconey should make for an even better rf sponge.

Agreed, height is everything at these frequencies. So Josh, you're the UHF Mil Air guru - what can I hear at my QTH here in MD? Got any frequencies to recommend?

You should have much more traffic in your region than I. One thing to do is to set a search mode between say 220 and 390MHz and let it run for a few days to normalise what's day to day in your area. Also, if you have a HAM club or scanner/dxing club nearby they often have a pdf or at least a webpage with scanner freqs. A lot of the more active freqs are nationwide, such as 311 and 321 and the like SAC primaries and also AICC will be active in your area.

Here's some resources;
https://www.radioreference.com/apps/db/?aid=7734

http://wiki.radioreference.com/index.php/North_American_Aerospace_Defense_Command_(NORAD)

https://forums.radioreference.com/service-specific-monitoring/
i hit this one (the mil, sat, and air forums) to see if anything is going on that i should be prepared to hear

This url allows you to enter a zip code and sort thru logs of milair traffic region by region, this url should show you everything logged on the site within 500 miles of you;
http://air2airshare.com/milaircomms/search_spots_zipcode.php?zipcode=21157&distance=500

As the ac are mobile radio stations, zooming around up there traveling perhaps hundreds of miles on a mission, you might catch some activity that is listed as being logged too far away to hear because of mission parameters.




Conveniently located near Vincennes Indiana.

Offline pinto vortando

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Re: Review Sirio Antenna SD2000N Discone antenna
« Reply #8 on: June 02, 2018, 0031 UTC »
Looks like a nice antenna,  good to hear that it seems to be working out well for you. :)
Have a Diamond D130J here which has withstood several ice storms and wind events.
Mounted on the chimney only up about 20' but seems to work fine, can even receive the ATIS from a couple of airports 15-20 mi away.
Fed with RG-6, my favorite coax.
Also have used it for FM broadcast DXing during tropo.
Hard to beat a discone for a one-size fits all general purpose VHF/UHF scanner antenna.
As for UHF air milcom, it is where you find it.  Although most civilian towers are equipped with UHF, the military tends to use VHF when communicating with them.
Not too far from a military airbase here but rarely hear anything on UHF.
If you are near a MOA or tanker refueling track you may have better luck.
« Last Edit: June 02, 2018, 2009 UTC by pinto vortando »
Das Radiobunker somewhere in Michigan

Offline Josh

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Re: Review Sirio Antenna SD2000N Discone antenna
« Reply #9 on: June 07, 2018, 1544 UTC »
Here's some more mil air freqs;

UHF-VHF Military


311.000 AM   STRATCOM/ACC primary
321.000 AM   STRATCOM /ACCsecondary
243.000 AM   Distress/guard
121.500 AM   Distress/guard
415.700 NBFM Air Force One/Two
407.850 NBFM Air Force One/Two
282.800 AM   All services search & rescue
287.800 AM   USAF/USCG air-sea rescue
381.300 AM   Air Combat Command (ACC) primary
381.700 AM   USCG search & rescue
381.800 AM   USCG search & rescue
239.800 AM   USAF weather
342.500 AM   USAF weather
287.400 AM   USAF refueling air to air nationwide
287.425 AM   USAF refueling air to air nationwide
295.400 AM   USAF refueling air to air nationwide
296.200 AM   USAF refueling air to air nationwide
297.300 AM   USAF refueling air to air nationwide
297.600 AM   USAF refueling air to air nationwide
297.625 AM   USAF refueling air to air nationwide
314.300 AM   USAF refueling air to air nationwide
314.325 AM   USAF refueling air to air nationwide
324.400 AM   USAF refueling air to air nationwide
336.100 AM   USAF refueling air to air nationwide
341.400 AM   USAF refueling air to air nationwide
352.900 AM   USAF refueling air to air nationwide
354.200 AM   USAF refueling air to air nationwide
358.200 AM   USAF refueling air to air nationwide
359.100 AM   USAF refueling air to air nationwide
359.125 AM   USAF refueling air to air nationwide
361.700 AM   USAF refueling air to air nationwide
366.300 AM   USAF refueling air to air nationwide
368.600 AM   USAF refueling air to air nationwide
369.200 AM   USAF refueling air to air nationwide
370.400 AM   USAF refueling air to air nationwide
372.300 AM   USAF refueling air to air nationwide
375.700 AM   USAF refueling air to air nationwide
375.925 AM   USAF refueling air to air nationwide
376.000 AM   USAF refueling air to air nationwide
376.075 AM   USAF refueling air to air nationwide
376.125 AM   USAF refueling air to air nationwide
376.175 AM   USAF refueling air to air nationwide
376.025 AM   USAF refueling air to air nationwide
376.075 AM   USAF refueling air to air nationwide
384.600 AM   USAF refueling air to air nationwide
385.400 AM   USAF refueling air to air nationwide
388.400 AM   USAF refueling air to air nationwide
391.800 AM   USAF refueling air to air nationwide
394.600 AM   USAF refueling air to air nationwide
394.900 AM   USAF refueling air to air nationwide
228.600 AM   NORAD
228.900 AM   NORAD
234.600 AM   NORAD
235.900 AM   NORAD
238.400 AM   NORAD
239.700 AM   NORAD
254.200 AM   NORAD
260.800 AM   NORAD (AICC)
260.900 AM   NORAD
261.400 AM   NORAD
267.000 AM   NORAD
271.000 AM   NORAD
272.000 AM   NORAD
273.400 AM   NORAD
274.400 AM   NORAD
282.600 AM   NORAD
278.400 AM   NORAD
287.700 AM   NORAD
288.400 AM   NORAD
293.600 AM   NORAD
293.800 AM   NORAD
299.000 AM   NORAD
309.400 AM   NORAD
316.300 AM   NORAD
320.600 AM   NORAD
324.000 AM   NORAD
327.900 AM   NORAD
238.000 AM   NORAD
336.600 AM   NORAD
341.800 AM   NORAD
346.200 AM   NORAD
346.900 AM   NORAD
348.200 AM   NORAD
351.500 AM   NORAD
355.200 AM   NORAD
359.400 AM   NORAD
359.800 AM   NORAD
374.000 AM   NORAD
377.000 AM   NORAD
386.000 AM   NORAD
387.800 AM   NORAD
390.200 AM   NORAD
397.800 AM   NORAD
398.000 AM   NORAD
364.200 AM   NORAD
264.900 AM   NORAD
255.400 AM   Military to FAA
225.400 AM   USAF ground control 1
275.800 AM   USAF ground control 2
289.400 AM   USAF ground control 3
335.800 AM   USAF ground control 4
342.500 AM   USAF weather
344.600 AM   USAF weather
281.000 AM   Air Tanker Common
251.900 AM   ANG primary
303.000 AM   ANG secondary
259.000 AM   ARRS Tactical
252.800 AM   ARRS Tactical
381.000 AM   ARRS TActical
344.600 AM   FAA pilot -metro
314.600 AM   Military contractors flight test
345.400 AM   Military contractors flight test
382.600 AM   Military contractors flight test
130.650 AM   AMC Command Post VHF
319.400 AM   AMC Command Posts
297.000 AM   AMC air to air
384.600 AM   Air Refueling air to air
385.800 AM   Air Refueling air to air
388.400 AM   Air Refueling air to air
391.800 AM   Air Refueling air to air
394.600 AM   Air Refueling air to air
394.900 AM   Air Refueling air to air
396.200 AM   Air Refueling air to air
286.300 AM   Air Refueling air to air
339.200 AM   Air Refueling air to air
343.100 AM   Air Refueling air to air
266.500 AM   Air Refueling air to air
267.800 AM   Air Refueling air to air
276.100 AM   Air Refueling air to air
279.800 AM   Air Refueling air to air
283.900 AM   Air Refueling air to air
289.500 AM   Air Refueling air to air
291.100 AM   Air Refueling air to air
295.800 AM   Air Refueling air to air
314.500 AM   Air Refueling air to air
318.000 AM   Air Refueling air to air
322.800 AM   Air Refueling air to air
322.950 AM   Air Refueling air to air
352.600 AM   Air Refueling air to air
352.700 AM   Air Refueling air to air
391.000 AM   Air Refueling air to air
276.500 AM   Air Refueling air to air
286.200 AM   Air Refueling air to air
286.900 AM   Air Refueling air to air
287.400 AM   Air Refueling air to air
364.200 AM   ACC primary
264.900 AM   ACC secondary
41.500  AM   ARMY helicopters towers
148.000 AM   AIR Force/ARMY common

Here are the UHF nationwide frequency allocations for USAF auxillary (backup)
transmitters and "BUTTON" channel identifiers. Note: these are not classified
frequencies and have been widely published.

These frequencies are usually reset into an aircraft's auxillary 20 channel
Colins UHF transceivers. The primary transceiver is usually preset for the
20 most used frequencies for any given wing or squadron. Those "BUTTON"
frequencies are not standard but the following nationwide frequencies are.

(all frequencies are AM mode)

GUARD:     243.000 MHz
BUTTON 1:  265.500 MHz
BUTTON 2:  266.600 MHz
BUTTON 3:  267.600 MHz
BUTTON 4:  268.600 MHz
BUTTON 5:  269.900 MHz
BUTTON 6:  270.100 MHz
BUTTON 7:  271.600 MHz
BUTTON 8:  272.700 MHz
BUTTON 9:  273.500 MHz
BUTTON 10: 274.800 MHz
BUTTON 11: 275.800 MHz
BUTTON 12: 276.400 MHz
BUTTON 13: 277.200 MHz
BUTTON 14: 278.400 MHz
BUTTON 15: 279.400 MHz
BUTTON 16: 280.500 MHz
BUTTON 17: 281.200 MHz
BUTTON 18: 282.800 MHz
BUTTON 19: 283.000 MHz
BUTTON 20: 284.200 MHz



Conveniently located near Vincennes Indiana.

Offline radiogaga

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Re: Review Sirio Antenna SD2000N Discone antenna
« Reply #10 on: June 07, 2018, 1754 UTC »
Nice, thanks for this list.

rgg

Offline ThaDood

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Yeah... My fellow Disconers out there. I've always wondered about this on Discones, below the actual disc array the GND radials reflect signal towards the horizon, but above the disc it would appear that signal should go straight up to space. So, the question is, has anyone tried using a Discone antenna for satellite communications? I certainly have a rig for it, a TS-2000X.
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Offline RobRich

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Re: Review Sirio Antenna SD2000N Discone antenna
« Reply #12 on: June 10, 2018, 1418 UTC »
VHF/UHF satellites are often circular polarized. Check out an eggbeater antenna for a basic example.
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Offline Josh

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Re: Review Sirio Antenna SD2000N Discone antenna
« Reply #13 on: June 10, 2018, 1700 UTC »
A disconey can rx the birds, however the birds have no relation to horizontal or vertical as most are spinning to give them some centripetal stability in orbit rather than just tumbling wildly. So they use circular polarity to eliminate the variability of their signals as seen by an earthbound receiver. Cough. Here's a link to a home made cp antenna for rxing the mil birds;
https://forums.radioreference.com/satcom-space-satellite-monitoring-forum/181378-mt-magazine-uhf-satcom-antenna-project.html
Conveniently located near Vincennes Indiana.

Offline ChrisSmolinski

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Re: Review Sirio Antenna SD2000N Discone antenna
« Reply #14 on: June 10, 2018, 1733 UTC »
Serendipitously, I have been using my discone this morning to receive various satellites, while testing some tracking software I am writing (it will become part of DX ToolBox).

It works very well for the ham sats on 2m and 70 cm, as well as the APT weather satellites on 137 MHz.
Chris Smolinski
Westminster, MD
eQSLs appreciated! csmolinski@blackcatsystems.com
NRD 545 / netSDR / AFE822x / AirSpy HF+ / KiwiSDR / 670 ft horizontal loop / 500 ft northeast beverage / 58 ft T2FD / 300 ft south beverage / 43m / 20m / 10m  dipoles / Crossed Parallel Loop