putting all my RG213 to use and repairing the T2LT

With the crimp-on plugs having arrived earlier this week I set to work fitting them to the cables, starting off with the RG213, which is all now terminated and can be put to use, all of it tested into a dummy load showing no mismatch, these cables should see me through for a while, and will be used to feed antennas over the longer RG58 that came from the cut off piece of the groundplane antenna, which will receive a plug hopefully tomorrow.

The T2LT had a cut in the feedline outer jacket, I have cut this out and crimped on a new PL259 at that point, it will be tested tomorrow provided the wind dies down sufficiently, if not Wednesday, I noticed this cut during the Activate All Counties event last summer but the antenna was still working as the braid had not been compromised, just the outer jacket.

Another antenna I hope to test tomorrow if it gets completed and the wind dies down is the second dipole for 2-meters made from the metal strips found inside the rubber part of car windscreen wiper blades, the antenna is deliberately too long for 2-meters so will be cut to length in the field, it will be fed with the RG213 I have and the QYT KT8900D will be taken with me as it is less prone to pager noise than the Leixen VV-898 and once the SWR meter is removed the HTs may be damaged having a heavy coax connected to them, and should this antenna work it will be my go-to portable ops antenna, for campsite use I'll use my copper-wire dipole as this does work fine as I have had it on the air before.

I will post results of the new dipole on YouTube and on here, the T2LT, however, I will just post on here as I know the antenna does work OK

73 de 2E0EIJ/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

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

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