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81
Technical Corner / Re: 12m antenna mast very practical
« Last post by jvok on December 08, 2025, 10:24:34 pm »
Also £70 for the Radioworld 12m one seems steep. You can get 10m ones on ebay for £45, could tape a bit a plastic conduit to the top if you're really desperate for the extra 2m.
82
Technical Corner / Re: 12m antenna mast very practical
« Last post by jvok on December 08, 2025, 10:17:43 pm »
I've used a 12m fiberglass mast up a very big hill for some long weekend stations in the past few years. Was surprisingly stable even in the wind, the whole mast would flex but it wouldn't topple over. Although I did have the telescoping sections collapse in on themselves once overnight, which took the station off air. Seems when rainwater gets in between the sections it lubes up the joints and lets the whole thing telescope down, I suspect once one section goes the others go with it.

Originally it had an end-fed flowerpot using RG58 duct-taped to the side, but I could never get it to match better than 1.5:1 and the coverage was patchy. Later I changed to a ladder line slim jim also taped to the side. That matched easier and gave much better coverage. Running 100W I got good coverage over about 35 miles and furthest reception was 65 miles away up another big hill.

Right now I have a 1/4wave GPA in the loft made from alu tube with the legs just sitting on the floorboards. After some trimming and bending the legs it matches almost perfect to 1.05:1, although moving it at all makes it go out of tune because the alu sheet I used for the centre piece is too thin for the weight of the elements, so the legs flex a lot. I run half a watt into it usually and get full quieting stereo coverage >1 mile away and patchy out to 3-4 miles. Distance record for full quieting was 8 miles with the car radio parked on top of a nearby hill. Also occasionally run 50W and get out to ~20 miles. This is just from the loft of a 2-storey house maybe 10m ASL. I bet it would work great up the really big hill, probably too heavy for the fiberglass mast though.

In a previous property with a decent sized garden, I used a similar mast as a monopole with a #12 wire run up the inside and radials made from alu fence wire buried under the grass. Used on MW with a loading coil wound from #12 wire on a piece of plastic soil pipe, then tuned with an L network using a valve radio tuning cap. Tuned up nice but was very inefficient, only got a couple of miles of staticky coverage with 1W. Probably needed much more power to get anything useful out of it. Also tried winding the loading coil on a ferrite core but found it was too lossy with any ferrite mix that gave a realistic number of turns. It would give a really wideband match which barely changed even with the antenna disconnected, which I figure means all the power was going into the ferrite and not the antenna.

Same antenna worked really well on SW (without the loading coil). Was resonant just above 6.2MHz without any tuning needed. With 5W was picked up on an SDR about 140 miles away.
83
London Pirate Radio / Re: Radionecks.co.uk
« Last post by jvok on December 08, 2025, 08:53:33 pm »
Guess they just had to change a few valves in the server

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Technical Corner / Re: 12m antenna mast very practical
« Last post by Schmellenschmellen on December 08, 2025, 12:25:28 pm »
Very flexible for all radio things.
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London Pirate Radio / Re: Radionecks.co.uk
« Last post by MonTaylor on December 08, 2025, 09:15:55 am »
yes i just seen this as well!
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London Pirate Radio / Re: Radionecks.co.uk
« Last post by ZoZo on December 08, 2025, 05:45:01 am »
Yes I just checked and all seems to be systems go!

Mr G must of been busy getting it all up and running again. I see that NRG Kits NZ is also back up.
87
London Pirate Radio / Re: Radionecks.co.uk
« Last post by Carlos on December 08, 2025, 01:40:31 am »
RN seems to be back up and running now!  Weird but good 👍
88
Technical Corner / Re: 12m antenna mast very practical
« Last post by ZoZo on December 07, 2025, 12:37:37 pm »
I've used these fibre glass telescopic poles before but I have the "SpiderBeam" variant which is more or less identical I guess, however I never thought to use it in the way this guy has; I've only ever used them for EFW on MW and HF, typically with a air wound loading coil at the base on a PVC waste pipe. I did share this on the RN forum some time ago. I later used a toroidal FT 250-2 core with much success and made a simpler and easer installation.

I guess this would be ideal for a pop-up weekend station transmitting from a high wooded area. ;)

89
Technical Corner / Re: 12m antenna mast very practical
« Last post by Schmellenschmellen on December 06, 2025, 03:50:53 pm »
12.5m antenna tip has a good chance of getting out quite well. It would be above average roof lines of 2 storey houses. Way way above bungalow rooflines which are what 6m - DJ Commode and MC Zimmerframe rocking the airwaves !

Even on the flat it will go a good way, you could even put something under the mast near whatever the bottom is attached to and get the tip to 13M on a still day. Maybe for a couple of hour blast over to your mate's house or something. For old lang sine on NYE.

Maybe some man about the house audio or Robin's nest ? :D

90
General Discussion / Re: Social Media Websites Broken
« Last post by radionortheast on December 06, 2025, 10:14:17 am »
unlikely to be gone for long though, maybe we could do with an influlencer, mr transmitter man
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