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

Monday, 31 January 2022

Fun with fitting roof bar mounts for antennas

I've fitted roof bars to my car and mounted the two antennas to them, the bars are coated in plastic and their mounting hardware is powder coated, however the bolts holding the fitting kit parts to the car showed continuity to the bodywork, the CB antenna at the very least needs bonding, which I have done using a piece of 27A DC rated cable, but this may be posing a problem itself so I will need a braided strap, while DC continuity is all well and good there could be reactance in the copper cable used, so a braided battery strap is needed instead.

This would be run from the bolts on the CB mount. then one of the bolts holding the roofbar mount fixing plate onto the mounting points on the car.

Using the wire, which is stranded, I got two low-SWR points either side of the CB allocations (SWR remains high within the band) once the mount was bonded, with the wire at the full spool length (2-meters or so) the SWR was much lower but it really needs bonding.

The 2/70 colinear antenna is offset from the centre towards the driver's side of the car, early tests on the VNA suggested that on 2-meters this antenna is working fine so I do not know where the antenna is getting its ground from on that band, I've not checked this on 70cm as yet.

As the VNA battery ran out during tests today I tried to power it from the car charger, this created a ground loop because the car electrical system has its negative grounded to the body as well as is the case in many modern vehicles.

Tomorrow I will pick up a braided earth strap of suitable length and try this on the car to bond the CB antenna as I suspect this copper DC cable I've used may not be working as expected.

73 de M0WNU/26CT730

Saturday, 29 February 2020

both antennas arrived, both scheduled for YouTube upload by Monday

I now have both antennas that I ordered, however the Thunderpole Boomerang antenna was to be delivered by Parcelforce (or Parcelfarce as I call them because they are incredibly useless) and they failed to deliver it to a neighbour as instructed, ignored the fact I rescheduled and left it at Catterick Garrison Post Office meaning after filming the video for the Sirio Hi-Power 4000 (and subjecting it to 70MPH due to a trip to nearby Darlington to do a bank run) I had to call at the Post Office to collect it, with that done editing work was finished for the Sirio antenna and the Boomerang unboxing video was filmed.

A big surprise with the Sirio was that I did not need to adjust it, SWR under 1.5:1 across all 80 channels, for the most part, the top end of 27/81 was about 1.4 which is acceptable, I was to compare between my K-Po and Zetagi SWR meters however this did not happen because another vehicle parked next to my car before I could do that, and the driver did not seem happy that I was even up there, probably because I don't own a dog, unfortunately public land means I have a right to go up there, it is ideal for radio given height and forms part of my mobile standardised test route, now I have the antenna I will be doing a dry run on video before actually doing anything on the air to show you the route from the car.

The only part to do from the perspective of the new antennas is the on-air test of the Boomerang, once it is up and tuned, given the fine adjustments that may be needed I won't bore you and give a final SWR reading as per the K-Po meter, the Zetagi meter, and the one built in to the President Grant II.

I will be working from 4pm tonight and as ever will be monitoring UK 19, which is usually full of the burner brigade running illegal power to speak to their pals which the 4 watts can do fine for them but they generally don't have a good understanding of this fact, that and they have the squelch turned all the way up which is a bit ridiculous really, maybe even with them I may notice a difference on this antenna on receive, the one thing that will be noticed is the fact I have a bigger antenna on the car.

73 de M0WNU/26CT730

Wednesday, 26 February 2020

A couple of antennas on their way

I have placed an order for two antennas, a Sirio Hi-power 4000 for the car and a Thunderpole Boomerang for the home QTH, these antennas should, hopefully, work to set my base line for CB testing in a mobile environment, the base line is to be set as the Thunderpole T3000, the mobile antenna being as long as realistically possible, the boomerang coming in close to the 'spider antenna' for size.

Of course these antennas get a video on YouTube, the first one will be the Sirio Hi-power 4000 as that is the most straight forward to install, installation will be done at my new radio test ground above Richmond at the Hurgill Road end of the old racecourse.

The other reason I chose the Sirio Hi-Power 4000 is due to the similarity between it and the antenna loaned to me (see a previous video on my YouTube channel) which I since had to return as the amateur that loaned me it needed the magmount, the Orbitor/Springer antennna on the car was always going to be temporary, and the Hi-Power 4000 will work with 10-meters though I would need to shorten it and I was never comfortable doing this with a loaned antenna so it is my intent to buy a second Hi-Power 4000 to be tuned to 10-meters so I just swap the antennas over depending on if I choose to use 10-meters or 11-meters.

For CB, tuning will be done on my Thunderpole T-3000 with the car engine running to ensure the radio is running at it's maximum power output, SWR will be checked across the entire 80 channels using 2 SWR meters, my K-Po meter and my Zetagi meter, these meters will both be used with the boomerang when it goes up and tuning will be done on the Grant II, once this is done my base line can be set, all my radios will go through it, even my handhelds with car kits will be subject to this to see how they perform once a suitable speaker-mic can be obtained that won't jam them on transmit.

I will set up a scoring system for the standardised tests, also with a temporary base antenna I'll be able to retest the handhelds in the local area for a follow up video to "Handheld CBs, are they any good?".

Keep watching this space

73 de M0WNU/26CT730

Tuesday, 5 June 2018

homebrew dipole working

Last night I got my homebrew 2-meter dipole antenna tuned and working while the rain held off, to use it I clamped the upright to an open window and the boom with the antenna on the end was outside the window, GB3CD was able to be accessed but it seemed to be below my squelch and a little in the noise, as were a couple of the stations on the S12 net I discovered, one in Darlington could hear me as I could hear him just fine, from the location given the station in Darlington was on the other side of Darlington to myself up near the retail park and car dealers, this was enough confirmation the antenna was in fact doing its job satisfactory, GB3HG and GB3IR obviously were not going to prove a challenge for the antenna given their locations.

Tomorrow if the rain holds off and the weather is good I may set up a portable station on Richmond's old racecourse with this antenna, the radio I will take I have yet to decide, also undecided is if I will go QRP or not, my VV898 can go as low as 5 watts (QRP levels) however the KT-8900D can only go to 10 watts at its lowest settings, after all this antenna is meant to be a portable design requiring nothing more than a screwdriver to disassemble the support from the boom, the VV898 may of course need reprogramming depending on how it is currently configured.

The next antenna I'd like to make is an antenna to work the FM satellites as I have still yet to do that, this dipole is my third successful antenna, the first being the T2LT for CB work and the groundplane antenna for 2-meters that was my original homebase antenna.

The coax on the antenna itself is a short run of RG58 to a BNC, this meant I have had to use a BNC-PL259 adaptor and a SO239 coupler to connect the feedline, which is the repaired feeder that was from the groundplane antenna after it was cut and it works great and is fitted with a crimp on PL259.

I shall see what happens tomorrow and see what stations I can work simplex if I go portable.

73 de 2E0EIJ

Sunday, 3 June 2018

Rebuild of my homebrew 2-meter dipole near completion

I have spent today rebuilding my homebrew 2-meter dipole, previously it was just a dipole centre made with the neutral conductor of twin and earth cable, and it did fail at some point before the QTH move, yesterday I went out and got some parts and today I have got it assembled to somewhat functional, or at least receive anyway as I’ve not had opportunity to tune it

As should be known with me I prefer to build my own antennas rather than buy them, though I make exception for mobile use, and I feel building antennas is in the true spirit of Amateur radio, and my eagerness to build rather than buy antennas would make Marconi very proud indeed

I hope to finish and tune the antenna tomorrow, it will have a pair of clamps fitted to the support to allow it to be attached to anything that can support it, though it is lightweight in general, and I plan to give the support structure a little more rigidity as at present it is a little more flexible than one would like.

The antenna will spend its time connected to my QYT KT8900D and will be used with at most 25 watts, and spend most of its time being used on FM, the inspiration to build this antenna was down to me discovering a net on S12 at about 9pm or so every night, as I have the FTM-400 in the car I tend to listen while I work and am in the car, I don’t transmit usually while working, except in exceptional circumstances, and once this antenna is working I would like to maybe join in on this net on S12, assuming from my home QTH the other stations in the net can actually hear me.

I rarely work simplex given my current antenna situation but this should be set to change, especially with an antenna I can install and remove very quickly indeed.

I will post more as progress is made

 

73 de 2E0EIJ

Monday, 7 May 2018

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

Wednesday, 21 February 2018

home made groundplane antenna tests

I have recently fitted a new PL259 to the home made groundplane antenna after finding one, though I do intend to replace it with a crimp-on type, testing has not gone smoothly though.

Initial tests in the shack showed high SWR, initially this was traced to the RG213 feeder I'd used to add a bit of distance, this needs new PL259s as there is a short in one end (unsure which), removing this the antenna still appeared to be out of tune despite the fact the radials and radiating element all have had no length removed, testing this afternoon in the living room the SWR dropped, final tests will be conducted in the open.

I did, despite following procedure, not realise that I was testing on a frequency in use, I was advised of this and checked other frequencies as matter of course.

Testing will continue in the next few days given time all being well.

73 de 2E0EIJ

Sunday, 26 February 2017

Magnetic loop antennas–a follow up

As I have mentioned previously I have a desire to build a magnetic loop antenna for HF use, primarily with my CRT SS9900 on 10 metres, though something that could cover 12 through to 10 metres meaning will work on CB as well as I still have a keen interest in that side of things despite holding an amateur radio foundation licence and hoping to go for my intermediate exam very soon, as alluded to in my last post.

My antenna situation as you know is very poor right now, made worse due to the fact I live in a first-floor flat, though I have a CB antenna in the attic it functions very poorly with high SWR readings and the need of a tuner to prevent damage to rigs connected to it, though this antenna works on 10-meters as well the tuner does not and to get the SWR to safe levels requires it be tuned with both sides turned all the way up to 10 (the unit is a Euro-CB EM-110 and is really suited to 11 metres rather than 10 metres), 2 metres is currently done with an antenna on a biscuit tin, also poor but it does work.

This is where the magnetic loop comes in, and I saw a YouTube video showing a design made out of copper tubing, with a power meter on the larger loop itself, a variant of this design was also on YouTube by an English member of Charlie Tango (of which I am a member with the callsign 26CT730) for CB use, with the right capacitor and correct dimensions I should be able to build a loop to this design (without a power meter fitted to the loop itself as I intend to fit the loop with a remote tuning system utilising a stepper motor and gearbox) and be able to start using 10 metres, despite the poor conditions at this time on that band I am eager to give it a go, also as I have not played with 11 meters since I scrapped my old car this would be a good opportunity as I understand CB is alive and well and there are regular nets held now, even on the midblock using AM and SSB since those modes became available to UK CB operators in 2014, but naturally I am keen to give 10 metres a go, whether I get a working magloop before or after I get my intermediate remains to be seen however I intend to make sure I get on 10 metres regardless, I have invested in equipment for that band I may as well use it.

I know I can get copper and plastic tube locally but for a suitable tuning capacitor I may have to look to rallies to do so, the requirements are that the tuning capacitor will work happily up to 4kV (though I suspect 50 watts is far below this but I like the idea of a safety margin).

The antenna will be connected with a suitable SWR meter in line almost permanently, my Zetagi Mod. 203W is perfect for this as it covers a frequency range of 26-30MHz for TX power measurement and 3-200MHz for SWR measurement.

I will post more on this subject as it progresses

 

73 de M6RSQ

Sunday, 11 December 2016

Amateur satellite

After watching a segment of episode 12 of TX Factor about operating through satellites I thought I would give this a go myself as all I need to do this is a suitable dual-band HT, as all mine are Chinese one would think they wouldn't be suited, as they can do what the offerings from the big names can do then they are fine for the purpose.

The satellite I am interested in, and as noted on the TX Factor episode referred to above, is SO-50, as it has an FM transponder, with uplink on 2-metres and downlink on 70cm, as it would be massively impractical to use the -600kHz split on a satellite due to the size of the cavity filters used at 2-meter repeater sites that achieve this so the signal goes up on 2-metres and comes back down on 70cm, but it isn't that straightforward as the Doppler effect has to be compensated for, programming the HT with the frequencies for the satellite beforehand will save you trouble here, the frequencies for SO-50 and other Amateur satellites are available on the Internet.

Knowing when the satellite is to pass is another thing you need to know, I have already gone ahead and downloaded two pieces of software for this purpose, on my Android phone I have AmsatDroid Free, and for my laptop I have Orbitron, the latter software being mentioned in the same TX Factor episode noted above, and this runs fine on Windows 10, so now I know where SO-50 is at any given time the next bit requires I be able to transmit from my HT through the satellite and my HT's rubber duck antenna simply will not do, for this a Yagi is the best antenna to use, but it needs to be of a design that will work on both bands, the most popular antenna appears to be the "Arrow" antenna, the original of which is actually made from arrows for the antenna elements, and because we're doing cross-band operation we also need a diplexer (this is correct, it is not "duplexer"), which from what I can tell is simply two passband filters, one high-pass for 70cm and one low-pass for 2-metres.

The Arrow antennas are not cheap, so in the spirit of Amateur radio it makes perfect sense to build one using bits from the junk box, and from a DIY store (B & Q in my case as it is the closest one to the home QTH), and I like to build rather than buy antennas where I can to save money, and considering that one may simply use their arm to move the antenna with the satellite it needs to be lightweight, wood for the boom would work well here, but if you do use wood it should be varnished to protect it should you be out on that hilltop and the heavens open, waterproofing the coax connections is also advised.

Once you have all the information regarding your chosen satellite, an antenna, a programmed HT, go out and make some contacts, but be aware that satellite QSOs through SO-50 are similar to contesting, usually callsign, location (locator square) and signal reports as the satellite passes for a short duration and is often very busy, listening before keying up is well advised, as is the use of headphones so you can hear the satellite better, also run the radio with an open squelch.

As a foundation license holder I am restricted to 10 watts, as is anyone with a foundation licence, antenna gain may push your actual radiated power beyond this level so dropping the radio to a lower power setting may keep the foundation licencee within their power limits and still legally use the satellite, gain and other such factors are beyond the scope of this blog, and from what I understand SO-50 doesn't need more than 10 watts anyway into it and by the time the signal gets there it probably falls well below that.

Having a second person on hand to assist with the operation may also be a good thing, as they are not transmitting they do not need to be licensed, adding a second pair of headphones for the assistant to help with logging may be a good thing too, the assistant can also help position the antenna leaving you free to carry out the QSOs.

And finally, building the antenna simply requires a search on Google as there is a lot of information on the subject and many designs are available, and you could further this and build the diplexer as commercial ones are about £30+ depending on where you go, and you get the pleasure of building the entire thing yourself if you do, and save money.

I look forward to working some stations through a satellite very soon, just got to get the festive season out of the way first.

73 de M6RSQ

Sunday, 13 November 2016

Possible solution to my antenna problems

Now as you are most probably aware by now, operating from home is difficult for me because of the antenna arrangements, at the moment the 2-meter antenna for home is the old one from my car stuck on top of a biscuit tin (and it doesn't work brilliantly), for 70cm it's the same antenna but I rarely work 70cm and stand no chance with an indoor antenna anyway, and 11-meters (that's CB radio to the not-so technically minded) makes use of an Excalibur loft antenna into an ATU specifically for that band as otherwise I have SWR readings in excess of 10:1 but this could also be the dodgy PL259 on the other end of the coax feeding the antenna but time has not been on my side to get into the loft.

I have a CRT SS9900 as you know, which has seen nil use since removed from my old car last year, it has had it's 2 fuseholders reinstated and powers up fine from an ATX PSU (as I don't have any other PSU for it and the one powering my CB and 2-meter gear is rated at 7A whereas the current draw of the SS9900 is higher than that at full power, this radio is not connected to an antenna and for the sake of legality is in "HF mode" so I can use 10-meters if I choose.

An antenna to operate 10-meters is needed, a CB antenna could be used and cut down here as some of these are cheap, however as I plan to only operate 10-meters from home for the main a different approach is needed where I don't have to mess about in the loft as it's full of dust and nasty fibreglass insulation and put up and remove temporary antennas.

Enter the magnetic loop

The magnetic loop antenna is not obviously an antenna to the untrained eye, it has a smaller "Faraday loop" to couple it and a variable capacitor of sorts to tune it, usually a large one as when transmitting even at QRP the capacitor can and will exhibit high voltages, they are narrow banded and the rating of the tuning capacitor gives the range of what the loop should operate at, my interest is one that can potentially operate between 40-meters and 10-meters as I do plan to upgrade my shack for other HF bands as and when I can, probably with a second-hand HF rig with the power wound down to at most what I am able to use.

Commercially built magnetic loop antennas are very expensive to buy, about the cost of a radio in some cases, the vast majority of operators build these themselves at a fraction of the cost of a commercial one, usually sourcing materials to build the loop itself is generally easy as they can be made of copper tube (preferably painted to disguise it and protect it from copper thieves) which is available from either auto parts suppliers as brake lines or DIY stores as water pipes, refrigeration line would work too, though most suggest diameter of the tube is important, I won't go into this in depth as it's beyond the scope of this blog and there's plenty of information on the internet.

It is the capacitor to build one that is the difficulty to obtain, you could build this yourself or you could find the appropriate capacitor on the Internet, important is that it needs to handle very high voltages without flash over, as running at even a few watts creates very high voltages in the capacitor, also a remote tuning arrangement should be built here to tune the antenna to your operating frequency, again all this is outside the scope of this blog and Google can be helpful here.

One of the pros of these antennas is the amount of interference received on the bands is very very low if not nil, quite useful in the modern age as modern electronic devices generate more and more interference which blights the Amateur HF operator to no end, the other pro is that it is a small antenna compared to other HF antennas which normally result in complaints by people who have no understanding of the hobby.

I plan to put one of these antennas together and put it outside in a very discreet manner, to get it connected I require a jumper through the window, Comet Antennas make these and they are sold by Nevada Radio for a reasonable price, and I have plenty of self-amalgamating tape left, I'm still on the first roll, so waterproofing the plugs is not a problem.

Another reason I want to go onto HF is to operate CW, as I am planning on learning morse code again when I have time to sit and do it, for me to do it on 10-meters I'd need an Anytone AT-5555 or one of it's many variants as the CRT-SS9900 (Anytone AT-6666) does not have CW on it, but that's something for another day

I'll update this in due course.

73 de M6RSQ

Monday, 2 May 2016

2-meter dipole revisited

Yesterday I dug out my homebrew dipole for 2-meters, and the dipole centre I bought from the Blackpool Rally and reassembled the dipole onto it, this was then hung up but the SWR was reading high, between 2 and 3 on the meter with the radio (the Leixen VV-898) at 10 watts, not good, moving it seems to have brought the SWR back down to the 1.7 it was at, still not brilliant but at least it's below dangerous levels for now, I suspect it's being affected by objects indoors and is best placed outdoors however the centre is not waterproofed and I have no means to hang it outdoors yet, my plan is to waterproof the centre with self amalgamating tape (another yet used Blackpool purchase) and put it onto my fibreglass mast and see what it can really do, the mast won't be extended to full-height as it is in need of TLC but it still has sufficient height to get out, this will give me a much more reliable SWR reading.

For the fibreglass mast to work as intended it needs to be fitted into a base, a parasol base from a DIY store should suffice here, I do need to make sure this tuning is done before I tape up the centre in case I need to do any more work so a dry day for the first run, if we even have a summer this year, would be good, and I could potentially put a Slim Jim on here later and save the dipole for other work, I could also put a lightweight Yagi on here, as I still wish to operate CB (my Grant II is in the shack for this very reason) I can put my T2LT on here, assuming it still works which it should do, on 2-meters I should be able to get out much further on the dipole so more simplex calls should be possible, I have no antenna for 10 meters despite having the rig for the job which may be the next antenna I work on, and with the mast on a parasol base it makes it temporary therefore should get around planning permissions, so let's see what I can get away with antenna wise.

73 de M6RSQ

Sunday, 1 May 2016

Slim Jim antenna revisited

As you may be aware, I built a Slim Jim antenna for 2 meters at the club sometime over a year ago but left it on the floor in my hallway for some time so I think it suffered damage and put the SWR above safe levels, upon suggestions from two other club members I intend to build another Slim Jim, after finding some instructions on the Internet, out of 450 Ohm ladder line, with the antenna enclosed in conduit either in a dark colour or painted in wood stain to blend in with my windows(the new windows are a dark wood effect outside) as the intention is this antenna is put outside, I've seen instructions that suggest to use a clip-on ferrite to stop common-mode currents but I may use the tried and tested choke approach instead.

I plan to get the feeder for this antenna into the flat by using a short piece of thin coax through the window so it will still shut, and running a short length of RG213 inside to keep the losses down, rig wise at the moment will be my Leixen VV-898 until I obviously get something that can do SSB as well, at the moment my rig purchasing priority is for the Yaesu FTM-100DE for the car and a replacement 2/70 antenna as the small one I currently have isn't brilliant and I'd rather have something improved for System Fusion, though I might try this out on the Slim Jim before it goes in the car assuming I get this antenna built and up before the rig is ordered (or bought from the Hamfest in September)

Before I do this I need to make sure my "shack" is in order again which I can spend tomorrow doing as it's a Bank Holiday, then I'll move on to getting hold of the parts I need

73 de M6RSQ

Saturday, 21 November 2015

A bit more time dedicated to radio

Firstly with my Leixen VV-898 on the bench rather than in the car (I had replaced the fuse holder for a mini-blade type after the regular one fell apart) and connected to the power supply I thought maybe it is a good idea to play with antennas so I dug out my 2-meter slim-Jim that I had built at the club some time ago, only to find it was not working as it should (the SWR was a bit high so I figured it was kaput as it had been on the floor in the hallway for some time), a T2LT cut to the right length was my next attempt, again this did not work, then finally I relented and assembled a dipole, this too, despite being cut to about the right length, was not working with a high VSWR, though it was lower on 70cm, what gave? Turns out the choke I had wound was too far from the feedpoint, so I cut the excess coax between the choke and antenna out (I did this so I did not have to redo the choke), after resoldering the antenna elements (two pieces of the neutral conductor from high-current twin and earth cable) to the coax at their new position and rehanging the antenna from my winter washing line in the living room and reconnecting it to the rig, the SWR had dropped though still read between 1.5 and 1.7 on the meter, better than it was but could still be better however it handles the 10 watts the radio gives it fine, all I now have to do is finish it off and hang it up outside the window.

I have also had a look into APRS, as there appears to be transmissions on the APRS frequency in the locality, which I believe is coming from MB7USD as aprs,fi isn't really showing a lot otherwise, I have been working to get the VV-898 to be able to TX on APRS but thus far have only got it to receive into my shack computer, and I don't yet have a passcode to do Internet-only operations as yet, as I have decided to decommission both my FRN gateways indefinitely some time ago as I want to focus a bit more on the Amateur side of things I plan to modify the auto-key circuit I built for the CB gateway to use it with the VV-898 for APRS as it sounds like something that might be worth playing with and the Yaesu FTM-100DE has this onboard as well and as I plan to get one of these for the car (as the box can live under the seat or in the boot out of the way) I may as well use the APRS feature on it, I'll hopefully be looking at one of these up close and personal at the next club meeting intermediate training pending.

I also have the APRS software installed on my laptop computer, of course not having a passcode as yet means I cannot transmit onto the APRS system but that should change soon, with a crude but working antenna up I should have no problems transmitting all being well, so let's see what APRS is all about

73 de M6RSQ

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

Tuesday, 16 September 2014

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

Sunday, 7 September 2014

T2LT progress update

Today, as the weather was nice, I dug out the beginnings of my T2LT antenna and got to work measuring it up and finishing it off, though I have yet to tune it yet.

Tuning will take place as soon as a suitable pole can be acquired, the pole MUST be a fibreglass pole, a carbon or steel pole will upset the antenna and make it useless, given how busy I have been of late with other things it's been a bit difficult to find time to get the T2LT sorted, hopefully I can get it tuned down and it will work nicely, a temporary solution to a problem I shouldn't even have and perfect for hilltop DX, which I hope to do before the weather starts to turn bad, so I'll get on with it sooner rather than later.

Also it's a couple of weeks to go before the Amateur radio club supposedly starts, I will still be going to Colburn that evening but if it's a no-show there is not a lot I can do about it, but if not then it's progress for me.

So I most certainly will be on CB soon, and possibly the Amateur bands not long after.


73 de 26CT730

Sunday, 20 July 2014

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