Discone versus Amateur white stick..

[bigpimp347]

whether this is made a sticky or not i don't care..

tested using quality RG58 and aerials in same location..
Discone the type with the vertical element so capable of transmit.
White stick i think a Watson X-30 type (three 18" radials)
i also used an MFJ 269 analyzer.

i found the lowest SWR's were on the white stick at around every 10mhz from 31mhz upto 460mhz.

31mhz 2.9
41mhz 2.8
50mhz 2.7
60mhz 2.4
70mhz 2.4
78mhz 2.0
87mhz 2.0
96mhz 2.3
104mhz 2.2
113mhz 2.2
123mhz 1.7
132mhz 1.7
140mhz 1.1
152mhz 1.0
160mhz 1.4
170mhz 1.5

then the MFJ goes to UHF.

420mhz 1.2
430mhz 1.2
441mhz 1.7
450mhz 1.3
460mhz 2.0

there was an increase in between each reading sometimes upto and over 4.0 but thats not to say the receive would be bad.
bear in mind the aerial is a dual band so some of the design could be a factor in the readings being high in between the low readings.
all readings were around 50ohms some as low as 30ohms some upto 65ohms.

the Discone read totally different, bear in mind these are 25 to 1300mhz and TX capable on 50mhz, 145mhz and 433mhz areas.

48mhz 2.1 30ohm
116mhz 2.1 25ohm
117 to 142 was always below 2.0
127mhz 1.4 50ohm
134mhz 1.3 50ohm
and 415 to 453 below 2.0
430mhz 1.1. 50ohm

so the discone had a better SWR curve it seems than the white stick..
but not so good to TX on 50mhz or 145mhz but ok on 430mhz and also useable on airband for TX..!!

now in my opinion for the best RX you want an aerial thats TUNED a lot of these scanner aerials are just random lengths of wire inside tubes (ok roughly cut to a certain frequency area)
and discones that claim to 'work' 25 to 1300mhz..are probably more likely to be random bits of rod not really tuned anywhere..

i tried the discone first and receive was ok, but my 1/4 dipole on VHF was better.
then i tried the white stick, this knocked spots off the discone.
it even received better than my 1/4 wave vertical on the stack..!!

so now i have the white stick on the stack and reception is up 50% if not more on what i can hear, i am even hear stuff i couldn't hear on my own white stick which is on the facia board 5ft lower !!

end of the day, it's up to you what you buy, or what you believe, but sales gimmicks, claims and jargon can win every time to ignorant and un educated people..
if a shop says a discone will work 25 to 1300mhz and they put £50 on it, you'll believe it because they say so..
but if a total stranger says a white stick will work better by 50% or more and they cost around £10 less, you'll believe the shop nearly every time..

try it and see i will only use a white stick on my scanners, i know they are tuned for TX and are tuned to work..

[Dagnabbit]

I thought I read somewhere once that a discone is horizontally polarised (i.e. from the disc rather than the cone) so that might account for dramatic differences?

[Andy]

I thought I read somewhere once that a discone is horizontally polarised (i.e. from the disc rather than the cone) so that might account for dramatic differences?

I'd like to see a comprehensive 'antenna range' test on a discone re efficiency, polarisation etc. Someone with the right knowledge and access to a wide-open field and some portable test gear could write a really good article.
The test could compare the discone with say a dual band vertical (like bigpimp did) and a SuperKingStick Pro II deluxe.

My guess is that a discone is predominantly vertically polarised because the elements of the 'dipole' are one above the other.

[thedeerhunter270]

Interesting tests - but SWR is only one part of the story imho.

When what I've read is, the radiation angle of a discone is can actually be negative on some frequencies, rather than say +15 or something for an X30. So if you live on a hill, a discone may work well for you. Whereas, if you live in a valley, a quarter wave ground place may be better with its high radiation angle.

The discone is supposed to work over a 10:1 ratio, if the base frequency is 100Mhz, then the SWR will be fairly consistent to 1000Mhz. But, as I say, the radiation angle wont be.

What I think is, different users will have varying results due to their own topology.

[bigpimp347]

the dis cone i used was a vertical version, the one with the top section and whip..
some do not have a vertical whip part and are horizontal.

i measured the SWR as both are meant to be transmitted on, and as an example they are tuned for TX on said frequencies,
meaning if they are god enough to TX there they should be tuned pretty good for RX..

in the 20 odd years i've had scanners i've only ever used one discone, that lasted a couple of weeks before i got an old dual band white stick off an amateur, since then i've sworn by them..

i only did this test as a guy gave me a discone, and i was in two minds in up grading my live stream aerial from the 18" up and down dipole..!
needless to say it's now running the white stick...discone is in the loft awaiting someone gullible enough to buy it

[Dagnabbit]

I thought I read somewhere once that a discone is horizontally polarised (i.e. from the disc rather than the cone) so that might account for dramatic differences?

My guess is that a discone is predominantly vertically polarised because the elements of the 'dipole' are one above the other.

Wikipedia (and others) agree with you
and also says "The radiation pattern in the horizontal plane is quite narrow, making its sensitivity highest in the plane tangent to the Earth's surface." or in other words, I presume, best for people on the same level as the surrounding area.

I wouldn't want one outside as they scream "naughty scanner freak lives here!"

[kurisu]

So is the conclusion better than the discone? As a newbie I have no idea what the bolded numbers mean

48mhz 2.1 30ohm
116mhz 2.1 25ohm

[bigpimp347]

the first part was testing frequency, the next is the SWR if it was to be transmitted on, and the last was the ohm's of the aerial at the point of test.

to be honest i have always found an amateur white stick to work better than any discone..
and if fed with RG-213, URN76, URN-67, RG-8 or other better lower loss coax you will get good results..

as i say i mostly listen to VHF and UHF and some airband and the white stick is not far of all the bands i want to listen to, so results are good..
unlike a discone thats not always that good, and to be honest in this test non were better on the discone.

plus the white stick has less of an impact on the eyes that a discone

[thedeerhunter270]

So is the conclusion better than the discone? :

The short answer is yes. For the most part an X30 antenna will give you better performance than a discone for the majority of signals you'll likely to want to listen too.

But, if your interest is military air, you may be better off with a discone.

[littlemo]

I thought I read somewhere once that a discone is horizontally polarised (i.e. from the disc rather than the cone) so that might account for dramatic differences?

A discone is verticaly polorised even though it has a flat disc on top, thats why you see them at airports. but it is weapon of choice in the aviation industry for its bandwidth as the vhf airband is a staggering 18mhz wide . This has been slowly changing to colinear type antennas over the years .

[RadioPixie]

I always assumed that a discone is vertically polarised.

I often thought in the 80's of converting a Thunderpole mk 2 or 3 into a discone but never got hold of a secondhand one to try it out.

The guy who writes the Scanning articles in the Radio User mag recommends a 6/2/70 white stick for scanning.

Personally I use a 2/70 Watson white stick and it's a good scanning antenna.

[stratocaster]

I'm looking at getting outside antenna for my base stations,nothing too obtrusive but something which will pull in 50MHz to 1.3+ GHz.

[Andy]

Strat, you'll struggle to get that coverage in one antenna. As stated above, a 6/2/70 (50/144/432MHz) aerial will be fairly decent for freqs up to 500 MHz, but beyond that you need something more specialised. You can get 2/70/23 (144/432/1296MHz) antennas, but in my experience they don't work very well on 1296.
My advice would be to optimise your system for 50 to 500 MHz, as that is where you'll hear 99% of stuff.
After that you may want to add a specialised antenna and coax for 1296MHz.

I know you want something unobtrusive, but 'unobtrusive' and 'effective' don't usually go together when it comes to aerials!

[bigpimp347]

you won't a lot if anything above 500mhz any way
so ignore all these 'wideband' aerials, they're wide band because scanners are..
they would sell many if they only covered 68 to 512mhz would they (unlike scanners that do)

i'd just go for a triband or dualband amateur aerial..

[stratocaster]

Cheers to you both! Will settle for what you recommended as as both of you have stated,not much gets sent at above 500MHz.