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Showing posts with label bazooka antenna. Show all posts
Showing posts with label bazooka antenna. Show all posts

Saturday, 22 November 2014

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

Saturday, 15 November 2014

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