Advice for dipole antenna on terrace house roof

[SW_UK_UGR]

Anyone have any advice for putting a 15w low power half wave dipole antenna on the roof of a row of terrace houses?

There are neighbouring aerials along the roofs for peoples TVs etc.. so my main concern is how much interference this would cause to my neighbours (who might care but might not). I cannot lift the antenna more than a couple metres high from the roof, if that, as it will be really visible from the front of the house which is on a main road. Even though I will only be using it at night time, it may look pretty bait.

This is only a temporary solution until better locations are found for broadcasting times.

I could put it in my garden up a tree although it will probably be mostly shielded by the house (a good 20-30 metres away maybe more)

There is also a telephone wire pole out the back of the house which has no cables connected, its just the wooden pole and metal climbing pegs, but it is preettty high and I would need to invest in more cabling to reach the TX if I was to go with this idea and somehow get it to the top.

I will post some follow up pictures below in the replies when I have taken some.

This is the antenna I will be using (no amplifier) - https://www.pcs-electronics.com/power-h ... -1477.html?

Powered by the MAXPRO7015+ 15W - https://www.pcs-electronics.com/maxpro6 ... -2434.html

Thanks

[tokingmenace]

Not the best option to run direct tx from your house - but if it's only now and again with 15w, you will prob be fine.

The main thing is to check you are not causing any local interference tvi. If people start to have interference and notice
a new antenna in the area, they tend to start asking questions.

What about mounting your antenna to a 'pull up mast' or making something out of scrap poles. That way the antenna is only in the air
when you are on at night. Something you can easily drop down in the day.

Personally I would use an antenna with some gain, to give you more erp, preferably a resonant antenna on the freq you choose to use.

[SW_UK_UGR]

Thanks for your reply

Yea I only plan on doing it a few times from my house to play around with the new TX and test distance etc.. I don't particularly fancy losing my set up and beloved record collection!!

What would be the best way to check if I am causing interference other than just checking my own TV?

Yea I was only planning on having the antenna up whilst im on at night and it would be packed away again by daylight.

I will add some pics tonight when im home

[McDonalds]

I can run 30 watts in my loft and freeview is OK but have to pick the right dial bottom band being best for me.
also have aerial in garden this means not as much RF its also away from the house on a pole 3 floors high.
signal only goes about 6 miles but there lots of buildings.

[Albert H]

A dipole isn't the right aerial for the job! You need to use something with a ground plane to prevent downward radiation into the houses. Your best bet would be a ⅝-wave vertical with ¼-wave ground plane rods. You could bolt it to a chimney on a short pole and leave it up there - if anyone asks, it's a CB aerial!

Another thing to consider is that the feeder should be as short as practical - you don't want to lose your expensively generated RF in heating up a wire! The telegraph pole idea is only OK if the rig is at the bottom or even part way up the pole!

15 Watts with the right aerial from a reasonably high site will go for miles!

[SW_UK_UGR]

The aerial was originally perfect for what we were going to do with it but plans changed, will look into the ground plane idea, although i only plan to use it there a few times

[SundayGroover]

I used the NRG half-wave vertical when I operated from home (most weekends for a year or more!). Mounted on pole well above roof height and using my 20w TX covered a very acceptable range!

[SW_UK_UGR]

ground plane antenna has been sorted nice one for the advice guys

[Albert H]

Good luck!

A properly matched ground plane aerial always works better than a simple dipole. You'll be pleasantly surprised by how far your little signal will travel.

[piraterx]

I remember many moons ago we disguised a dipole with a For Sale sign on the house!

Drummed up a bit of interest,not from the feds but mr and mrs looking to mortgage their first house!!

[s2000]

I remember many moons ago we disguised a dipole with a For Sale sign on the house!

Drummed up a bit of interest,not from the feds but mr and mrs looking to mortgage their first house!!

Lol, it's quite a good idea!

I have often thought it would be good to make a slimjim style antenna disguised as a Christian cross... and fit it to a high church! That would have the rig theives confused

[SW_UK_UGR]

[piraterx]

Is that what you call CROSS POLARISATION?

[radionortheast]

Anyone have any advice for putting a 15w low power half wave dipole antenna on the roof of a row of terrace houses?

There are neighbouring aerials along the roofs for peoples TVs etc.. so my main concern is how much interference this would cause to my neighbours (who might care but might not). I cannot lift the antenna more than a couple metres high from the roof, if that, as it will be really visible from the front of the house which is on a main road. Even though I will only be using it at night time, it may look pretty bait.

This is only a temporary solution until better locations are found for broadcasting times.

I could put it in my garden up a tree although it will probably be mostly shielded by the house (a good 20-30 metres away maybe more)

There is also a telephone wire pole out the back of the house which has no cables connected, its just the wooden pole and metal climbing pegs, but it is preettty high and I would need to invest in more cabling to reach the TX if I was to go with this idea and somehow get it to the top.

I will post some follow up pictures below in the replies when I have taken some.

This is the antenna I will be using (no amplifier) - https://www.pcs-electronics.com/power-h ... -1477.html?

Powered by the MAXPRO7015+ 15W - https://www.pcs-electronics.com/maxpro6 ... -2434.html

Thanks

I got that aerial a while ago to take to bits, it was hard to measure with the rig expert you don’t know co-ax inside of it, it was abit duff, its an end fed aerial and not wide band. You’d be better off making your own end fed aerial thought you’d have to have something like swr to measure, their fairly easy to make, afew turns of coax at the bottom, the amount of turns is very critical. You’ll problaly will get some reflected power with the aerial mentioned, unless your lucky.

[Genie FM]

Years ago I used 40 Watt to half wave vertical on a 12 ft pole attached to a chimney stack with lashing kits. I told everyone around I was a radio ham and didn't get any trouble at all limiting broadcasts to about 3 hours on a Sunday afternoon.

[Genie FM]

BTW pcs electronics gear is very expensive for what it is. If your'e interested I have a never used fm tx 1 watt o/p with psu for it and have a stereo coder, RDS unit choice of 2 , 50 watt pa ( 1/2 watt input0 and psu for same and a large fm vertical antena i think 7/8. Mike

[teckniqs]

Good luck!

A properly matched ground plane aerial always works better than a simple dipole. You'll be pleasantly surprised by how far your little signal will travel.

Gamma-Matched Dipoles are great and seem to me to work better than the 1/4 wave GP.

[Albert H]

Unfortunately, a gamma-matched dipole isn't truly omnidirectional (there's a null in the direction of the matching stub. Also, it's a 1 : 1 aerial, by which I mean 10 Watts RF in equals 10 Watts radiated. I've never seen a really accurately matched gamma-fed dipole - there are always matching losses.

If you use shaped radiation - like with a ⅝-wave - you don't waste energy upwards or downwards, it goes towards the listeners, giving an increased apparent signal strength. A properly matched ⅝-wave with ¼-wave groundplane elements gives at least 2dB over a dipole, and has a further advantage that minimises coax losses because it's inherently unbalanced - this can win you more than an extra dB over a dipole, so generally, a Real World™ ⅝-wave will give an extra "S"-point at the receiver.

If you're prepared to build something a bit bigger, the single slot colinear gives a bit more gain, and a twin-slot version is good for almost 6dB over a dipole. This is (effectively) free extra Watts without getting a bigger rig. The cheapest amplifier is an effective antenna!