70 MHz antenna for Sota use

If this is not correct to put links to commercial sites Please let me now so I delete this post.

After trying out the 29MHz antenna from Mr. Jeep and was satisfied whit its performance I asked him if he had a antenna for the 70Mhz band. he didn’t but most willingly he accepted to made one for me as a sample.
This is a telescopic whip antenna some 115-120cm long. Loading coil in bottom part and a BNC male connector.
I tried it on some sota activations and was happy with it.
So he now is making it for all and it is selling on ebay
http://cgi.ebay.co.uk/Ham-Amateur-4-Meter-70MHz-45-5-BNC-Telescopic-Antenna-/140467365445?pt=UK_ConsumerElectronics_SpecialistRadioEquipment_SM&hash=item20b481e645
Nice antenna that works some or a lot better than the small one who comes with most radios including even those on Tait handhold commercial radios.
A the loading coil is a little soft so in very strong wind I prefer not to use it as it may be destroyed.
He selling it in EU, LA, HB9 for £ 9.99 plus £ 2.80 in postage.
Cant make it cheaper at home.

73 de LA1KHA Kjell

In reply to LA1KHA:

Thanks for this info, Kjell. Very useful. (But he is quoting a very slow delivery time from Bangkok … 30 - 42 working days!)

I would add that Garex Electronics ( garex.co.uk ) have just started selling a “Flexiwhip” specially designed for the Wouxun 70MHz handy. It has the proper plug on the end (SMA socket). It’s a centre-loaded whip 50 cm long.

It is a bit more expensive, though … advertised at £19.95 plus £2 post and packaging.

73 de G3NYY Walt

In reply to G3NYY:

I would add that Garex Electronics (
http://www.garex.co.uk/aerials/flexis.htm ) have just started selling
a “Flexiwhip” specially designed for the Wouxun 70MHz handy.
It has the proper plug on the end (SMA socket). It’s a centre-loaded
whip 50 cm long.

Hi Walt,

I have one and, as an antenna, it works much better than the supplied helical - BUT, mechanically it needs a re-think. All the strain of the whip and loading coil are put onto an SMA connector and it will not last more than a minute or two in a high wind or if it is not handled carefully. I have a modification currently under evaluation which puts much of the loading onto the case of the radio (just like the helical does) and off the SMA connector.

Barry GM4TOE

In reply to GM4TOE:

I have one and, as an antenna, it works much better than the supplied
helical - BUT, mechanically it needs a re-think. All the strain of the
whip and loading coil are put onto an SMA connector and it will not
last more than a minute or two in a high wind or if it is not handled
carefully. I have a modification currently under evaluation which puts
much of the loading onto the case of the radio (just like the helical
does) and off the SMA connector.

Hi Barry!

Very interesting. I’ll look forward to hearing further details of your modification when your evaluation has been completed.

73,
Walt (G3NYY)

In reply to G3NYY:
Hi Walt I have made a Slim Jim from 300 ohm ribbon cable and its fed with mini coax and using a SMA to BNC connector on the Wouxun.This is very compact when rolled up and I attach it to the Sota pole with reusable tie wraps.For 6 metres I use an home brew delta loop.ATB Geoff G6MZX

In reply to G6MZX:

Hi Walt I have made a Slim Jim from 300 ohm ribbon cable and its fed
with mini coax and using a SMA to BNC connector on the Wouxun.This is
very compact when rolled up and I attach it to the Sota pole with
reusable tie wraps.For 6 metres I use an home brew delta loop.ATB
Geoff G6MZX

Hi Geoff!

I have also made a Slim Jim as you describe. I used the dimensions from the Summitsbase website and made it with black slotted twin 300 ohm feeder. The SWR is better than 1.2:1 and it works very well. I have used it for many SOTA activations.

73,
Walt (G3NYY)

In reply to G3NYY:
Hi Walt.I can`t claim any credit I did he same.ATB Geoff.

In reply to G6MZX:

Its worth bearing in mind for the Es season that HB9CVs and Moxons are commercially available.

73

Brian G8ADD

In reply to G3NYY:

I’ve got a Garex Flexi whip on my Tait Orca T5020 but must confess I’ve had very little joy with it anywhere. It might of course be the rig :frowning: I’ll take the whole lot with with me on this weekends jaunt (probably Worcestershire Beacon) and see if I have any success from there. I stuck it on my analyzer. The antenna is optimised for about 70.3mhz.

73
Tony

In reply to KD9KC:
Thanks for the replay. A yagi ore quad is always a nice option.
The 70MHz band is most for local qso on FM from summits in Norway.
Even if southern part of Telemark is highly populated with nearly 100.000 inh it is about 10 or 12 who have 70MHz rigs and I believe we are 3 with all mode capability. Next stations are abt 100km away. QSO is hard to come by…
If the sporadic E is present in this band I prefer to stay in the car and work some CW/SSB before it is all over.
have used cw/ssb from summits with dipole antenna, and qso is possible to capital area.

I hope you have a lot of fun on your US summits. Hope to qso you on HF bans some time.

73 de LA1KHA Kjell

In reply to G3NYY:

(But he is quoting a very
slow delivery time from Bangkok … 30 - 42 working days!)

FYI I ordered one on the day this was posted, and it arrived this morning. That’s 7 days.

In reply to M1MAJ:

(But he is quoting a very
slow delivery time from Bangkok … 30 - 42 working days!)

FYI I ordered one on the day this was posted, and it arrived this
morning. That’s 7 days.

That’s not bad from Bangkok, Martyn! Mine arrived from Garex the day after I ordered it … but it’s twice the price! I have done some tests with the Garex one. Over two different 10-mile paths, it’s at least 3 S-points better than the Wouxun rubber duck.

73,
Walt (G3NYY)

I ordered a antenna for LA1ENA Aage. Posted 26/10 and arrived here in Skien 2/11
That is 7 days post time to Telemark, bet if you live in big citys in UK it can be even faster.

http://cgi.ebay.co.uk/Ham-Amateur-4-Meter-70MHz-45-5-BNC-Telescopic-Antenna/-/140467365445?pt=UK_ConsumerElectronics_SpecialistRadioEquipment_SM&hash=item20b481e645

Hope our friend Aage will be happy now and forgive that I borrowed his antenna analyzer a little more than a week. (Sorry Aage I forget so fast)

73 de LA1KHA Kjell

In reply to LA1KHA:

bet if you live in big citys in UK it can be even faster.

You’ve not used the post service in the UK then? :wink:

Still 7 days for an international order is not bad at all and I’ll hazard a guess it spent longer in the UK than abroad.

Andy
MM0FMF

In reply to M0ZZA:

Well the Garex Antenna and Tait Orca T5020 performed admirably from Worcestershire beacon (which is more than can be said for the operator.) Must just live in an area with no 4m operators. The antenna is quite long and to be honest looks home brewed but is very light, flexible and well worth the money in my opinion.

Tony
M0ZZA

In reply to G3NYY:

Mine arrived from Garex the day
after I ordered it … but it’s twice the price!

I wasn’t fussed about the price difference but I was very keen to find a telescopic antenna as it will be much easier to carry.

In reply to LA1KHA:
I haven’t checked this out yet, but one of the ‘directors’ on my 4 element yagi (for 2 m), is just under a metre long… I’m sure it’ll be possible to use/adapt this as a 1/4 wave vertical for 70 MHz - with a home made ground plane…

Getting a “Wouxun” soon, so will try it out

73

Rob (G1TPO)

Duplicated entry !!! OOOHHH

In reply to G1TPO:

Rob G4RQJ has had some consierable success using a 2 element yagi on 70 MHz. I believe this is based around his 144 MHz Yagi but it certainly has some directionality & gain over a dipole, or J-Pole / Slim Jim.

73,

Mark G0VOF