The trusted T2LT antenna for 11-meters, how does it perform over a commercial antenna?

Well to find this out YouTube user "Amateur and 11m radio Tim" (sorry Tim I don't know your callsigns yet) rigged up a commercial antenna, a Sirio 4000, and a T2LT, needless to say those results were impressive.

I have built the T2LT myself as you know, and I know it works as I have got out on it and it pulls in a lot of stations though last time I had it out the conditions left a lot to be desired, however for 11-meters it is the most practical antenna you can get, it can be hung from trees or fibreglass masts and it gets you on the air, how much power it can handle is a different matter entirely as I have never actually tested this and there is no legal way to do that, however the T2LT gets its next outing at the end of June.

Going back to Tim's video, it is here so you can make your own decision on whether for portable 11-meter operation a T2LT or a commercial antenna is the right choice for you.

73 de 26CT730

T2LT revisited

I've been on an antenna theme recently, what with both a Slim Jim and a 2-meter dipole written about (the latter being made, the former an idea I can put to some use), and I continue with a favourite CB antenna of mine, the T2LT, the person who made the original video showing how to build this antenna, Gary 26CTX104, remade the video into a two-parter where he went into a little more detail and built another T2LT, it turns out the video was published well over a year ago and I'd not done a lot of CB at that point and was just starting out on Amateur radio, but CB is a bit of fun now and again but some good contacts can be made on 11 meters depending on the solar cycle amongst other things.

So, as you will know I already have a T2LT antenna built, and have tried it out but using only 4 watts into it (perhaps less on battery powered rigs as these radios are designed to run on 13.8V DC whereas my sealed battery is about 12 volts and a pack of AA batteries don't deliver much for long, handhelds are not counted here) though conditions were not favourable for me

So, the plan is this, get the antenna up on my fibreglass mast, inserted into a parasol base or attached to a secondary mast (no more than 1.5 meters) that will fit a parasol base (this avoids planning constraints as the antenna can be removed with relative ease), run a feeder to my "shack", plug the Grant II into it with my good SWR meter for CB in line (I have 3 CB meters and one VHF/UHF meter) and check to see how well it is tuned up, and try and make some CB QSOs (using my CT call if it is still valid which it should be), naturally I will be carrying out some other tests, I just need a volunteer to sit in the "shack" to transmit, as it's CB and anyone can use it without needing a license, for that test the CB magmount will go on my current car connected to the car adaptor of one of my handhelds, the Intek H-520 would be ideal for this as it has a large readable S-meter over the Midland Alan 42 Multi, though both have an S-meter.

So, I am keen to give this a go so Saturday will be a shopping day for some bits

73 de 26CT730

Equipment for PMR446 antenna upgrade ordered and a few other bits

I have placed an order for an SWR meter suitable for the PMR446 channels, I have also added tp this order some PL259s suitable for some cable I found I had lying about which is suitable for use on UHF but not as heavy as RG213, an SO239 coupler identical to what is fitted to the T2LT so the antenna and feeder can be connected together (I will be sealing this up with black sugru to protect it from the elements) and a SMA-F to BNC adaptor to fit the Wouxun in order to attach my Nagoya NA-771 to it when it becomes free again (once the Intek is on the bazooka and operating happily into it)

The SWR meter I have ordered covers from 140MHz (meaning I can use it on 2-meters to double check the slim-Jim on a radio and in situ once I have a license), all the way up to 525MHz (so PMR446 is included), my good CB SWR meter is valid up to 200MHz so for 2-meter antennas I can compare the readings.

The bazooka will be checked for SWR in two places, the first being at Whaston Road car park, my favourite DX spot close to home, the SWR will then be rechecked when the antenna is up in the air, I still need to add some rigidity to the driven element to keep it as vertical as possible (PMR446 units all have antennas that are near enough vertical as almost all type approved PMR446 radios are handheld units (the exceptions to this being the Intek DRS-5070 and it's cosmetically identical predecessor, the Midland BaseCamp446, and the Alan Base446, but these all can operate on batteries and are still portable rather than fixed like a base CB or home Amateur station, the BaseCamp446 has a mic holder on it's rear panel).

I expect to take delivery of the items I have ordered in the middle of next week, and I expect the PMR446 gateway to be moved off the Nagoya and onto the bazooka by the end of next week, range tests will then be carried out once the antenna is up, including to Northallerton, I look forward to seeing if at last I can make it there on PMR446, it's a big ask but it's worth trying.

73 de 26CT730

Bazooka antenna assembled

As per the instructions of Jason 26CTX965 on his YouTube video, I have assembled a PMR446 bazooka antenna using RG58 coaxial cable.

The choke was a little bit of a difficulty to find a former for to begin with but I simply cut the handle off a cheap toilet plunger (no great loss as I can replace it).

The antenna needs to be adjusted for SWR, I face two problems here, one of which is that I do not have an SWR meter that I can use on PMR446, my decent SWR meter only covers up to 200MHz, so I need to get a new SWR meter, secondly is that I need to be able to connect the antenna to a radio and a feedline, the feedline is not a major issue as I have an RG213 feedline for my portable CB work anyway, a radio is as the feedline is terminated with a PL259, fitting the antenna socket kit on my Intek MT-5050 will not work without an adaptor as this is an SMA type connector, the modded Binatone Action 950 as you know has a BNC socket so again needs an adaptor, and my Wouxun, though not strictly legal on PMR446 also has an SMA socket so again requires an adaptor, though I need an adaptor for the Wouxun to use the j-pole I made at the club the other night.

The ultimate idea of using this bazooka antenna is to improve range of the PMR446 gateway, the gateway radio is currently using the antenna fitted to it and is attached to the window with suction hooks to give it some height in the Catterick and Northallerton direction (it has NEVER reached Northallerton and been usable there, but as the A1 is in range, only just, then a better antenna is called for as the A1 is a major through route in the area and good coverage there would be a bonus, as the Intek DRS-5070 is not fitted with an antenna socket out of the box then this needs to be done, the BNC sockets are generally cheap to obtain (the same time I used for my SDR enclosure should suffice with the outer connected to a ground in the radio (negative side of battery box)

I'll update this when the antenna has gone on the pole and been checked out for SWR.


73 de 26CT730

Evening SSB net

Tonight I made an attempt to take part in an SSB net for a couple of hours on EU 28 USB, though I could hear a station in Corsica I was not able to get back to him, nor another Charlie Tango station on channel I heard in the back of the box, presumably Northumberland, there was  a lot of QRM from the US as well as some QSOs going on, but unable to reach them either.

The T2LT had tuned down fine so perhaps conditions were not favourable for me this time, if the weather is good I might give it another go next weekend, and perhaps work out a shelter that's somewhat better than my scooter's cover.


73 de 26CT730

T2LT update

With the new pole having arrived I strapped it to my scooter, packed up my Grant 2, my most decent SWR meter, my multimeter should I need to investigate any shorts, the dummy load in case I needed to check for any issues with the radio, which I did not need.

The pole was not 100% straight (it was propped up), the T2LT was slightly adrift at the top but otherwise fine, a small loop was also provided for tuning. but no tuning was needed as the SWR was below 1.5 at all times, reception was good across both UK and midband, the tuning loop was positioned slightly above the top of the pole with the main part of the antenna running the length of the pole, the choke also worked perfectly.

Should the weather be good on Saturday I shall be heading back up to the car park where I did the tests and will be going on air properly for the first time in a long time.

73 de 26CT730

Pole for T2LT ordered

I have put an order in for a suitable pole for the T2LT, though this pole was advertised as being a flag or windsock pole it would work fine for having a piece of wire attached to it, this will allow me to tune down the T2LT to a suitable degree, though the SWR may change on location but we will see.

The tuning will be done using my President Grant 2 off either the battery pack or the scooter battery, as I don't plan any proper QSOs, I will simply erect the pole and antenna, and either prop or fasten it to a fence post, I will find some velcro straps to allow a temporary fix to the pole, and a small cable tie to loop the top section for tuning, all I have to to is adjust this loop.

I intend to use the most reliable of my 3 SWR meters for this, the meter in the Grant 2 may not be accurate but will be on to see just how accurate the onboard meter of the Grant 2 actually is, also out in the open the antenna should receive across all channels, and also all modes now we have multimode CB, I look forward to finally seeing if my third antenna attempts (I made a dipole a few years ago out of a piece of coax (but forgot the choke), the coax being used later for the ill-fated inverted-V, the T2LT uses one component used in the ill-fated inverted-V, half of the choke core, it was integrated rather than detachable.

I have confidence this antenna will work well, but I have sufficient coax to make another should the need arise.


73 de 26CT730

T2LT progress

The choke is now wound, the PL259 plug is fitted, and the top of the plug where it meets the cable has had a small amount of Sugru applied to it.

On doing a Google search for "PL259 plugs and Sugru" it turns out that there is no record of anyone doing this which means either one of two things, I am the first person in the world to watertight the cable entry of a PL259 plug with Sugru or others have before me and not really made it public

The RG58 I used is reasonably good quality, it has good braid coverage and a good dielectric, I just now need to measure from the choke to the point in which I will be cutting off the braid, I then need to measure from that point to what will be the top of the antenna (so 8.5ft and another 9ft respectively as per 26CTX104's YouTube video, the 9ft top section allows for some tuning down, folded over and not cut as the VSWR may vary from location to location)

So I look forward to getting the next bit done, then perhaps this antenna will be up and I'll be on air soon :)


73 de 26CT730

T2LT choke dilemma

Now as you know, I am planning to build at least one T2LT antenna, using the design outlined in 26CTX104's video on his UKCBTV YouTube account, but I had a dilemma, what to use as the former for the choke, an important component that separates the antenna and coax as this antenna is not only a dipole for all intents and purposes, it is also made from the coax, I had a look at a few ideas, B & Q sold long lengths of soil pipe that had a slightly wide diameter and I could not transport on my scooter, Homebase were no good at all.

So I thought to myself "what do I already have that I could use?" after carefully measuring the diameter of various round objects (cocoa tin, golden syrup tin, fizzy drink bottle, cider bottle and empty marshmallow fluff tub) I then remembered that I still had the two pieces of tube I used for the choke on the ill-fated inverted-V dipole I was intending to use in the loft but for many reasons didn't, I measured this, bingo, 4" diamater, a quarter of an inch shy of 26CTX104's findings but should be fine if the turns are the same (around about 5, I've seen 5 turns on 4" former reported to work fine).

So, I intend to begin today by running out a short length of the coax I have, which is 100m of RG58 which I bought partly to do this, today, winding the choke, fitting a PL259 on the other end, sealing the plug up with some Sugru where the coax leaves it to stop water ingress (I have heatshrink but of the wrong diameter for the PL259), it will take around 24 hours for the Sugru to fully cure and I don't know if any operators have used it on their PL259s, perhaps this is a first, but perhaps not.

So, I'll let you know how I get on, also just need a fibreglass pole and some means to fasten the antenna to it, and I should be on the air very soon.


73 de 26CT730