Category: VHF/UHF Dual Band Antenna

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Wouxun KG-UV9K Purchase


For some time I’ve wanted a full duplex 2m/70cm handheld so I could have a go at working the LEO FM satellites during the summer months from the garden.

Searching through all the handhelds available today I came across the Wouxun KG-UV9K dual band, full duplex VHF/UHF radio.

Since I already own a Wouxun KG-UV980PL Quad bander (6/4/2m & 70cm) I’m familiar with the menu system and the very good build quality so I decided to research it further.

Wouxun KG-UV9K Full Duplex Hand Held
Wouxun KG-UV9K Full Duplex Handheld

Looking at the spec for the handheld it does everything I want and more whilst being reasonably priced.

Jumping onto the Martin Lynch and Sons website I found there were two listings, the radio on its own or the “Pro Pack”.

The radio on its own was £79.00 but, the Pro Pack was only £20 more at £99.00 and came with every option available for the handheld including a programming cable, 2 batteries and a rather nice carry case.

Wouxun KG-UV9K Pro Pack
Wouxun KG-UV9K Pro Pack

The full specification and other details for the “Pro Pack” can be found on the ML&S website but, here’s a brief summary:

Pro pack contains:

KG-UV9K Transceiver with 2 antennas

Two batteries
Two belt-clips
Software and transfer data Cable
Fast charger dock and Power Supply
Hand speaker mic
Battery eliminator
Manual
Wrist strap
Leather case
In-car charger
SMA-SO239 adaptor
Hands-Free kit

Like my Wouxun quad bander the handheld can also be configured as a cross-band repeater, something I’ve not yet found a use for but an interesting feature. Of course being a full duplex radio with two receivers you can listen to signals on 2m and 70cm simultaneously or transmit on one and listen on the other, a feature I’ve wanted for LEO satellite operations.

The radio is really easy to programme using CHIRP and easy to setup via the very logical menu layout. The hand held has a good solid feel to it and I’ve found the battery lasts a good 3-4 days even though I use it to chat with other stations via my AllStarLink node most mornings and the radio is left monitoring all day.

The larger of the two supplied antennas works extremely well having a relatively good gain. I can now easily get into my two local repeaters on 2m & 70cm from within the house, something I’ve never been able to do with my old Retevis RT85 even with a high gain antenna on it.

The receivers in the UV9K are head and shoulders better than that of the Retevis RT85, I’m hearing signals much stronger now and can even get into repeaters that I’ve never even heard on the old Retevis handheld.

The display on the Wouxun is bright and easy to read, even in bright sunshine which is great as I plan to use it outside a lot during the summer months.

The supplied speaker mic gets good unsolicited audio reports on transmit and has clear audio on receive with plenty of volume. The speaker mic doesn’t have any radio control buttons on it sadly, something I really like about the Wouxun UV980PL quad bander as you can control every aspect of the radio without touching the front panel. Would be a nice upgrade for the handheld if it every became available.

Overall I’m really impressed with the Wouxun UV9K Pro Pack. The radio performs very well, comes with every optional extra available and is a bargain at just £99.00.

If you’re looking for a full duplex handheld radio then I recommend you grab the Pro Pack before the offer ends.

More soon …

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Sign the partition to allow UK HAMs to put up antennas

There’s a new partition that has been started in the UK to allow UK licensed radio amateurs to install antennas and masts without planning permission.

https://petition.parliament.uk/petitions/755675

Partition to allow UK Radio operators to install antennas and masts.
Partition to allow UK Radio operators to install antennas and masts.

If you’re reading this and are a licensed UK Amateur Radio operator please click the link above/below and sign the partition so that we may highlight the subject with the UK government as the RSGB has failed to do this for us for decades now even though members keep asking them to do more on the subject.

https://petition.parliament.uk/petitions/755675

More soon …

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Wouxun KG UV-980PL Quad Band Radio

I recently decided to look into a 2m/70cm FM radio for the shack for use on the local 2m/70cm repeaters and was considering the offerings from Yaesu and Icom however, the Wouxun KG UV-980PL caught my eye as it is a quad band, full duplex radio. Not knowing much about Wouxun radios I had to do some research to get an idea of what it’s like. Generally the radio gets very good reviews and most mention the excellent build quality.

There are two versions of the 980P radio, the 980PL that offers 6/4/2m and 70cm bands and the 980P that offers 10/6/2m and 70cm. The 4m is a band I’ve been wanting to try for some time and the 980PL with it’s 4m band coverage became even more appealing.

Wouxun KG UV-980PL Quad Band FM Duplex Transceiver
Wouxun KG UV-980PL Quad Band FM Duplex Transceiver

I decided to take a trip down to Martin Lynch and Sons (MLANDS), a good 2 hours or more drive for me, so that I could get hands on with the radios that I had been looking at.

I invited Alan, G1SQB along for the ride and a day out playing with radios as he lives 3 miles away and we often chat on air.

Arriving at the store we grabbed a hot brew and set about playing with the great selection of radios on display.

I initially looked at the Icom IC-2730E, a dual band full duplex transceiver that has been around for about 10 years and has good reviews. As expected the build quality is excellent and very easy to use. I found I was soon able to set up memories etc via the front panel controls. The only draw back is that it isn’t supported by the CHIRP programming software that I use. Other than that it certainly meets all the requirements for a 2m/70cm FM transceiver

Icom Ic-2730E Duplex FM Transceiver
Icom IC-2730E FM Duplex Transceiver

Next I moved on to the offerings from Yaesu including the FTM-500DE 2m/70cm transceiver. The colour screen is very nice and the menu system very easy to use however, the price is getting on for close to double that of the other radios and it doesn’t really offer anything more that interests me since I’m only looking for an analog radio.

Yaesu FTM-500DR dual band FM Transceiver
Yaesu FTM-500DR dual band FM Transceiver

Sadly there wasn’t a Wouxun UV-980PL out on display and so I had to persuade the salesman to get one out of stock for me to play with. Unpacking the radio I was surprised at how good the build quality is, it really is comparable to the other radios that I had been looking at.

The Wouxun menu system is fairly easy to use once you’ve looked at the manual and got to grips the abbreviations used. The big plus is that this radio is CHIRP compatible with an optional programming cable (£19) and so loading the memories with repeaters etc will be extremely easy.

The Wouxun has dual receivers built in with a quad-plexer so, you can transmit on one band whilst listening to another band on the other receiver. One thing to note is that the 1st receiver covers all the bands, 6/4/2m and 70cm however, the 2nd receiver only covers 2m and 70cm so, it’s not possible to receive 4m and 6m at the same time. The radio also only has one antenna connection on the rear, would had been great if it had one connector for each receiver.

The really good thing about the Wouxun UV-980PL is that it comes with everything you will need, apart from the programming cable!

After much tinkering I decided to purchase the Wouxun KG UV-980PL, a Diamond V2000 6/2m and 70cm antenna plus 20m of Hyperflex-13 coax cable and connectors.

In the box you’ll find two mounting options for the removable head. There is a short connecting cable for use when the head is mounted directly on the radio body and a 5m long connecting cable for mounting the head remotely. This is really useful as I wanted to mount the head on a mic boom arm so that it’s easily accessible and didn’t clutter the desk space in the shack.

M0AWS Shack
Wouxun KG UV-980PL head mounted on a Mic boom arm

Since the radio also comes with the mobile mount I’ve fixed the radio body on the wall behind the PC monitor out the way. This setup has proven to be extremely good as I can see what’s happening on the display at a glance and easily grab the mic if called.

Programming the radio memories is extremely quick and easy using CHIRP. I had the local repeaters and my AllStarLink node frequencies and offsets uploaded to the radio in no time at all and was soon on air.

Programming the memories on the Wouxun UV-980PL using CHIRP
Programming the memories on the Wouxun UV-980PL using CHIRP

The microphone that comes with the radio is extremely good. You can operate most of the controls on the radio directly from the mic with ease and it has a good feel in the hand. Audio reports have also been very good and there’s no need to change it.

I’ve not yet got the new Diamond V2000 antenna erected but, I’ve been using the radio with my homebrew 2m/70cm end fed vertical dipole and my 4m band end fed vertical dipole and am getting excellent results. I can access all the local repeaters using the lowest power output setting and only have to use the medium/high setting for the repeaters that are further afield.

On the 4m band the radio performs well and I’ve been surprised at the distances I’ve been able to cover even though my 4m antenna is only 6-7m above the ground currently.

A few days after I got the new Wouxun radio there was an ARISS event whereby a group of Girl Guides would be talking to Astronaut Sunita Williams aboard the ISS. This was a great opportunity to test the receive capability of the radio and so I setup ready for the pass. Using just my simple 2m/70cm end fed vertical dipole I got great reception as can be heard in the video below.

Overall I’m extremely pleased with the Wouxun KG UV-980PL quad band radio and considering it’s much cheaper than the offerings from the main radio manufacturers it’s well built and performs extremely well. If you’re looking for a simple, analog FM radio for 6/4/2m/70cms then you can’t beat it!

More soon …

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Retevis RT85 antenna SWR

Since purchasing my Retevis RT85 2m/70cm handheld radio I’ve noticed that it seems rather deaf when using the antenna that came with the radio and isn’t as strong into the local repeaters as I imagined it would be.

Considering the local 2m and 70cm repeater isn’t that far from my QTH and there is pretty much a clear line of site view in the direction of the repeater I was somewhat surprised that on 70cm the repeater never breaks the squelch, even if it is set on it’s lowest setting of zero.

M0AWS Retevis RT85 dual band VHF/UHF Handheld Radio
M0AWS Retevis RT85 dual band VHF/UHF Handheld Radio

Connecting my home made end fed dual band vertical dipole at 10m above ground the performance of the radio improves drastically as one would expect.

Having recently purchased a JNCRadio VNA 3G antenna analyser I decided to connect the Retevis supplied antenna to the analyser and see what the resonance was like on the two bands.

The antenna is labelled as 136-174Mhz and 400-470Mhz. This is an extremely wide frequency range for such a small antenna and clearly isn’t going to perform that well over such a wide bandwidth.

Connecting the antenna to the VNA and setting the stimulus frequency range to 144-148Mhz I found that the SWR curve of the antenna wasn’t particularly good.

M0AWS Retevis RT85 Antenna SWR Curve 2m
M0AWS Retevis RT85 Antenna SWR Curve 2m

As shown above the SWR curve on the 2m Band is pretty poor. At 144.0Mhz it’s just over 3:1, at 145.496 (closest I could get to the 145.500 calling channel) the SWR is still 2.1:1. The antenna doesn’t really get close to resonance until 148Mhz where the SWR is 1.46:1.

With an SWR this high the radio will almost certainly be reducing the O/P power considerably to protect the PA stage from over heating due to so much power be reflected back into the transmitter. This explains the poor performance when using 2m repeaters locally and the somewhat limited range when using the OEM supplied antenna.

Looking at the SWR curve on the 70cm band, the antenna is much closer to resonance than it is on the 2m band but, it’s still not perfect.

M0AWS Retevis RT85 Antenna SWR Curve 70cm
M0AWS Retevis RT85 Antenna SWR Curve 70cm

At 430Mhz the SWR is 1.56:1, at 435Mhz 1.63:1 and 440Mhz 1.72:1. Since the antenna is much closer to resonance on the 70cm band I would expect it to perform better than it does.

Looking at the SWR curves over the entire supported frequency range of 136-174Mhz and 400-470Mhz, there is only one point of resonance on VHF around 148Mhz and on UHF around 400Mhz.

Retevis RT85 VHF Antenna SWR Curve
Retevis RT85 VHF Antenna SWR Curve
Retevis RT85 UHF Antenna SWR Curve
Retevis RT85 UHF Antenna SWR Curve

With such disappointing performance on both VHF and UHF I’ve decided to investigate making my own 2m/70cm antenna for the handheld to see if I can improve both the SWR on each band and the overall performance of the radio.

More soon …

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Dual Band VHF/UHF End Fed Vertical Dipole

Since purchasing my Icom IC-705 radio I’ve only used it on the HF bands. Since the IC-705 is a “shack-in-a-box” I thought it was about time I ventured up onto the VHF/UHF bands and add another string to my bow.

Since I don’t have an antenna for these two bands I’d need to build something. I’m not really interested in DXing on the VHF/UHF bands as I’d need a yagi or two, a rotator and would need to get the entire setup up high on the chimney on the house.

We’re very fortunate in that there are a good many repeaters on VHF/UHF in East Anglia with quite a few being well within range of my QTH.

So I decided to go with a simple vertical antenna of some sort that I could easily attach to the top of a 10m spider pole and pop up in the garden without too much hassle.

The simplest of all antennas to build for any band is an end fed vertical dipole. It’s made purely from a piece of coax cable, you can’t get much simpler.

Using some dimensions I found online I unrolled a length of RG58U and set about cutting it to resonance for the two bands.

To start I measured out 910mm of RG58U and put a piece of tape around the cable at the 910mm point. I then stripped the top 460mm of the outer and braid from the coax so that the inner wire and plastic insulation was exposed. This then left 450mm of coax with the braid still in place to make up the 2nd half of the vertical dipole.

At the 910mm marker I wound the coax 9 times around a 27mm former to create a choke balun. I taped the coil up to ensure it kept it’s shape, removed it from the former and then used a few zip ties to hold it in place.

VHF/UHF End Fed Vertical Dipole Diagram

The diagram above aids in visualisation of the make up of the antenna that is made from a single piece of RG58U coax cable.

Choke Balun made from 9 turns of RG58U on a 27mm former

I next wound some electrical tape around the point on the antenna where the outer insulation and braid ended so that it would stop moisture getting into the rest of the coax and causing problems in the future. I also put a bit of electrical tape across the top of the end of the wire to stop moisture getting into the inner wire and then a piece of electrical tape around the wire to ensure it was fully sealed.

Electrical tape wound around the point where the outer braid finishes

At this point the antenna was complete! It literally took a few minutes to make. I could now either cut the coax a few centimetres from the bottom of the coil and fit a PL259 or just continue the coaxial cable back into the shack and fit a PL259 on the end. I decided to go with the latter as it’s one less connection to make.

VHF/UHF End Fed Vertical Dipole taped to the top of a 10m spiderpole

Once complete, I taped the antenna to the top of a 10m spider pole and then ran the rest of the coax back into the shack and soldered on a PL259 connector.

Raising the spider pole up to its maximum length put the antenna some 10m up above the ground. Hopefully this will give me a relatively clear path to the local repeaters.

Plugging the antenna into the IC-705 and checking the SWR I found it was <1.2:1 across the entire 2m band and <1.5:1 across most of the 70cm band. It was perfect for what I wanted!

VHF/UHF End Fed Vertical Dipole up 10m on a Spiderpole

I configured the local repeaters into the the IC-705 memories so that I could easily switch from one repeater to the next with all the appropriate tone and duplex frequency shifts set at the touch of a button.

My local 2m repeater GB3PO comes in at 5/9+10dB without any preamp and the local 70cm repeater GB3IH comes in at 5/9+5dB without any preamp. I was really pleased with the results and set about having a chat with other local HAMs on the local repeaters. It’s been a while since I’ve used the mic on this radio and it made a nice change!

To my surprise I found I could get into far more repeaters than I ever imagined. GB3NB in Norwich is 5/8 as are a number of repeaters down in Essex. This gives me quite a scope for chatting on the VHF/UHF bands via the repeater network.

To my surprise I can also hear ON0WV in Brugge Belgium, unfortunately it’s on the same frequency as the local 2m GB3PO repeater and so often gets drowned out completely but, it’s good to know that when there’s a lift in propagation I should be able to get into the near continent without too much hassle.

If you’re looking to build a simple but, effective 2m/70cm vertical for local repeater access then I highly recommend making an end fed vertical dipole. It only takes a few minutes to cut the cable to length, remove the outer sheath and braid and wind the choke balun, it really couldn’t be any easier.

More soon …