inside or out

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para999
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Re: inside or out

Post by para999 » 09 Oct 2019, 14:31

just been thinking about what you said re a dipole in the loft couple of questions
can I use wire ( roughly the thickness of the centre braid of the rg cable ) instead of poles. ? or does it need to be thicker ?
if I use the inverted.. V.. presumable there must be a break between the 2 legs to allow the centre braid to fit to one side and the earth to the other ?
presumably the same would apply to the T fitting along the roof apex, otherwise the signal would short out ? as it does if you touch the inner to the outer on the cable
I have another but it depends on your reply to using wire ?
thanks

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Re: inside or out

Post by prettypolly » 09 Oct 2019, 20:22

If the op wants or needs a antenna I have a few here if he needs or wants one for nothing

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Re: inside or out

Post by 108EH002 » 10 Oct 2019, 14:10

para999 wrote:
09 Oct 2019, 14:31
just been thinking about what you said re a dipole in the loft couple of questions
can I use wire ( roughly the thickness of the centre braid of the rg cable ) instead of poles. ? or does it need to be thicker ?
if I use the inverted.. V.. presumable there must be a break between the 2 legs to allow the centre braid to fit to one side and the earth to the other ?
presumably the same would apply to the T fitting along the roof apex, otherwise the signal would short out ? as it does if you touch the inner to the outer on the cable
I have another but it depends on your reply to using wire ?
thanks
You can use thin wire but thicker wire will give you a better bandwidth or lower swr from 26.965 - 27.991.25 = legal 80 UK Channels.

Yes you need to seperate the 2 wires 999.

If you can use a solder iron,just remove the pl259 plug at the bee mount,the wire is already separated for you to connect onto.

If you need to start from scratch =

1 = Cut a couple of inches/50mm back from the end of the co-ax,through the black outer plastic that protects the outer braid,remembering not to cut through the braid underneath.

2 = Pull the braid back to reveal the white plastic that insulates the inner live wire,cut through at about an inch/25mm from the end.

You can cut through the braid lengthways and twist together and sit it at 90° to the inner live = you now have your 2 points to connect the dipole legs onto.

If you can't solder the wires,electrical chockblock connectors,just twist the wires together and insulate individually for added safety.

You can always use 2 or 3 thin bits of wire on each leg of the dipole,as long as they are connected at either end,and the same length..

You can use cable ties or electrical tape to keep them close to each other,if you want to thicken up your thin wire.

If you need more info just ask :thumbup:
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para999
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Re: inside or out

Post by para999 » 10 Oct 2019, 14:58

great thanks.yes I'm a dab hand with a soldering iron( well, I think I am, but some might disagree lol )but I think I would prefer to use cable connector strips.more chance of a permanent fix I fancy giving this a shot whilst I'm waiting for the handyman.i have some 0.8 mm wire but I might just try something thicker like 1.2 or 1.5 m.m what do you think ?
I have most of what I need already so the only extra will be the wire which isn't much from B&Q. I have had another listen and discovered I can reduce the background noise by putting the transformer further away from the set.is there anyway I can see if the transformer is actually causing some interference apart from lugging a car battery in the house and connecting to that ? at the moment I have the cb,swr meter, transformer, extra speaker, all screwed to a bit of plywood.
thanks for your help.

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Re: inside or out

Post by The Collector » 10 Oct 2019, 16:28

Get the power supply as far away as the radio's power lead will allow.

What power supply is it Danny, old transformer style or the newer type (or Scalextric type lol) and what amperage?

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Re: inside or out

Post by para999 » 10 Oct 2019, 16:50

hi don't want to break any rules about posting links but if you were to go on fleabay and put jetfon 810 in the search bar it will be there its 10 amp.
Last edited by para999 on 10 Oct 2019, 16:51, edited 1 time in total.

108EH002
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Re: inside or out

Post by 108EH002 » 10 Oct 2019, 16:51

1 = The 1.5mm will be better because its thicker and will be fine for a dipole.

2 = You can have the supply as far away as the length of the radio's power cables will allow,but usually 2 - 3ft is enough.

Once you know your swr is good you don't really need a swr meter inline,especially if theres one built into your G2 premium.

I bought 2 length of 15mm copper pipe and 2 jubilee clips to connect the live and earth wires onto the copper pipe = cost me £15.

Have used many different types of copper wire,and numerous lengths of all types of steel to make a homebrew dipole.

Cable off an old hoover/extension reel or even CB co-ax to name a few.
Last edited by 108EH002 on 10 Oct 2019, 16:55, edited 1 time in total.
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para999
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Re: inside or out

Post by para999 » 10 Oct 2019, 16:54

108EH002 wrote:
10 Oct 2019, 16:51
1 = The 1.5mm will be better because its thicker and will be fine for a dipole.

2 = You can have the supply as far away as the length of the radio's power cables will allow,but usually 2 - 3ft is enough.

Once you know your swr is good you don't really need a swr meter inline,especially if theres one built into your G2 premium.

I bought 2 length of 15mm copper pipe and 2 jubilee clips to connect the live and earth wires onto the copper pipe = cost me £15.

Have used many different types of copper wire,and numerous lengths of all types of steel to make a homebrew dipole.
yes I could do that thankyou

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Re: inside or out

Post by The Collector » 10 Oct 2019, 19:51

para999 wrote:
10 Oct 2019, 16:50
hi don't want to break any rules about posting links but if you were to go on fleabay and put jetfon 810 in the search bar it will be there its 10 amp.
Ah... a new-fangled switch-mode thingy. They can sometimes cause a bit of interference ("noisy" supplies) I've heard in the past, so yeah, a bit of distance may help matters.

If you can also somehow monitor your audio at some point too, you'll be able to tell if there's anything coming through with your audio like buzzing or electrical interference.

10amps is good though as your radio pushes a few watts on SSB and a 3-5amp may have struggled.

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Re: inside or out

Post by para999 » 11 Oct 2019, 16:50

ok update I've gone for the copper pipes along the ridge line in the roof space.it's early days as I've only just finished doing it.the swr is a tad high around 2-2.5 so I'm not tempted to key up at the moment.it seems the background noise has improved ( on some channels) so I can just about make out people right at the back of the box at say s2 on SSB as for UKFM forget it,it's still just as noisy as ever. I wll keep listening up over the weekend and see if I can actually hear anybody. I've been listening to the USB 27.555 which should give me a better idea.

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Re: inside or out

Post by 108EH002 » 11 Oct 2019, 16:58

Well at least the swr isnt in the red 999 = what is the length of each copper pipe ?

Sounds like its still too long,so cut an inch off either end at a time until the swr is lowest on 27.500 FM.

It will need to be slightly shorter if its horizontal than inverted.

If you have 8 1/2 ft of copper pipe on either side its too long for in a horizontal position just so you know 999,you might end up closer to 8 1/4 ft.

I know it is a bit of hassle but it should work far better than the whip is at present for you.

If the swr is far lower on UK CH 1 than it is on UK CH 40,its because the antenna is still too long.

You want the swr to be highest on 26.965 and 27.991.25 and lowest around 27.5 MHz ;) :thumbup:

I would be looking to have an swr of about 1.3 > 1 on EU CH 1 // 1.0 > 1 on 27.500 // 1.3 > 1 on UK CH 40.
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Re: inside or out

Post by para999 » 11 Oct 2019, 18:15

hi
I bought 2x 2metre 15mm pipes I lopped off about a foot off each to make sure it would fit but I made sure I ended up with 2 pieces the same length.
I attached the earth braid to one and the centre braid to the other.i made sure neither length was touching the other and suspended them from one of the timbers at both the same height sorry but I would have to go measure them if you want the exact length but as I say I made sure they were both the same length. swr is 2.5 0n both CH40UKFM and ch 1.i wasn't too happy with using the jubilee clips I was thinking I might be better using self tappers but presumably the wires must be making contact alright otherwise the readings would be way out

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Re: inside or out

Post by 108EH002 » 11 Oct 2019, 18:23

A 2m length is only 6 1/2 ft,you would meed to buy 3m lengths and cut them to 8 1/2 ft.

Another length and 2 straights = or use copper wire to make up the length.
Last edited by 108EH002 on 11 Oct 2019, 18:29, edited 1 time in total.
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para999
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Re: inside or out

Post by para999 » 11 Oct 2019, 18:27

that would be an overall length of 17 ft if that is correct it wouldn't fit length ways in my loft space, hence why I bought the 2m and lopped a foot of each and then it only just fit

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Re: inside or out

Post by 108EH002 » 11 Oct 2019, 18:31

As you stand looking at your house,it must be at least 20 ft wide ?
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