Help please ?...unknown antenna freq.....

[fires999]

Evening Forum,
Hope you've all recovered from the Superbowl?
Now be honest . Was it the football or Taylor Swift ??!! Lol..
Anyway was looking for some help please, I've been given an antenna however I dont know what frequency it is designed for.
ARNO ELECTRONICA COBRA 30EH
Stands about 3ft tall, diameter of a cd and is white plastic ( has 259 socket on side).
Shop here in UK once sold a 40m band. Mine has only the label 30EH...do you think that is 30m band (10mhz ?)
Any help be really greatful. Unfortunately I dont have an antenna analyser.
If you type description into Google you will be directed to YouTube video of the 40m version but looks identical.
Thanks as always in advance,
Kevin ( US Airforce in Europe Fire Department)

 

[AK9R]

My guess would be 30 MHz. Might be a CB antenna.

 

[fires999]

Evening forum,
Firstly thankyou for the reply and to all those who took the time to even read my post !
So further investigation shows that the 30EH markings mean it is designed for 30 meters, 10 mhz.
So my next question is again looking online, 10 mhz is quite a niche allocation with only a tiny segment allocated for amateur use - do you think the antenna would be ok for 1mhz either side ? Eg 9mhz or 11mhz ?
Thanks in advance
Kev

 

[alcahuete]

You might want to recheck that. There is no 3 foot antenna in existence that is going to work anywhere close to reasonably on 30m.

 

[fires999]

Morning,
Thanks for reply - getting confused now !
Online searches show EH11 as 11 meters, EH40 as 40 meters ..so my logic is mine says EH40 thetefore 30 meters ?
They are all same dimensions regardless.
A Google Search of
Arno EH40 antenna shows same that was available in a uk shop called Radioworld?
Kev

 

[K7MEM]

My guess is that you should be searching for information on a 10 Meter "EH" type antenna (capacitive). Search for "EH" all by itself. That's the only place where the wide bandwidth would make sense.

Here is a link for construction plans published by Lloyd Butler, VK5BR, for a 10 Meter "EH" antenna. Maybe you can match some of the dimensions. A look on what's inside would also be useful.

And here is more information published by Tom, W8JI, on the EH type antenna.

I don't think anyone has a high opinion of it.

But, size can fool you. I have a small mobile whip antenna (~3 feet) with a magnetic mount and a Radio Shack HTX-100 10 Meter SSB/CW radio. At the time I lived in Phoenix, AZ and had the radio and antenna installed in my car. I would talk a lot while on my way home from work, but mostly it was relatively local hams. However, one day, I called CQ and a station from Virginia came back to me. That would be about 2,000 miles. We talked for a while and then I parked, for safety reasons. The HTX-100 is switchable between 5 and 30 watts. So I switched to 5 watts. My signal on the other ops end went down, but only a couple of S-Units. It was still very readable. We talked for another 10 minutes and then signed.

I removed the radio from my car after that because, driving and talking on the radio was just too dangerous. My car had a 4-speed floor shifter and the radio only had a hand microphone. At intersections I often needed to turn the steering wheel, shift gears, and key the hand microphone. I would just run out of hands. Not to mention, adjusting the radio and looking at the readout.

 

[fires999]

Evening Forum,
Firstly thanks again for all those who replied. Its astonishing the effort that you all put in to help a complete stranger !
K7MEM - really appreciate your extensive response....yes it doesnt look particularly favourable from the article !!!
Now, I managed to contact the person who sold it to me over 2 years ago ..he confirms 10mhz and after conversation wants to buy it back ??!!!
So once again THANKYOU RR Forum.
Have a great long holiday weekend if in the USA.
As you know I'm a UK firefighter attached to a US Airforce Base here in the East of England, so the UK crew will try to cover so our US colleagues can spend time on Base with their families.
Take Care, be safe
Kevin

 

[alcahuete]

Now, I managed to contact the person who sold it to me over 2 years ago ..he confirms 10mhz and after conversation wants to buy it back ??!!!

Sell it. A 3' antenna isn't going to work worth a darn on 30m.

 

[fires999]

Looks like i'm going to be saying goodbye to the antenna.
Original seller who wants to buy it back has just got into CW and digital around 10.15mhz ?
If he can use it then good luck - just need to negotiate a price.
Thanks for advice,
Kevin