Indoor FM aerials - any recommendations?

[Pigmy Pony]

Last week I retrieved a Sony tuner I'd given a mate 20-odd years ago, which he never got round to using. (It's not anything special, cost me about 100 quid in 1995). Now when I originally used FM tuners back in the 80s, I had an aerial wire going out through the window frame, up the front of the house, and under the eaves into the loft space and connected to a giant aerial.

Well this time round I can't be arsed with any of that as I don't know if FM radio will even hold my interest in these days of gazillion DAB and internet radio station choices. I'm just after a low-cost discreet indoor jobbie to get me started.

Does anyone here still listen to FM radio, and have any suggestions?

[rigger67]

Back in the day, my very first proper hi-fi item was a hefty old Technics receiver, with one of those massive flywheels for tuning.
I just used some speaker wire and pulled it apart so there was a wide spread between the two "antennae" and fixed it to the wall behind some posters, using the drawing pins that held them in place to secure it.
It was just a question of looking at the display while you were doing it and waiting till you got the full four bars of signal strength.

It always sounded deep and rich to my teenage ears.

[Pigmy Pony]

Back in the day, my very first proper hi-fi item was a hefty old Technics receiver, with one of those massive flywheels for tuning.
I just used some speaker wire and pulled it apart so there was a wide spread between the two "antennae" and fixed it to the wall behind some posters, using the drawing pins that held them in place to secure it.
It was just a question of looking at the display while you were doing it and waiting till you got the full four bars of signal strength.

It always sounded deep and rich to my teenage ears.

Yes, I started out doing that in the early days ("wet string" I heard it described as), and it worked fine for me, though I think its effectiveness would very much be dependent on your location... I might just nip to B&Q for a couple of metres of bell wire and give it a go, see if it'll work here.

My mate gave me an "indoor" aerial, but it has a 'male' termination, as does the tuner, so I would have to get a female/female connector. Also, it's ugly as sin, and I don't want it to look like the storeroom of a long closed-down branch of Tandy's.

[Barry]

I have a Belling & Lee female/female converter you can have. Remind me of your address and I'll pop it in the post for you.

[Macca]

You're up high so the T shape bit of wet string should be fine.

[Pigmy Pony]

I have a Belling & Lee female/female converter you can have. Remind me of your address and I'll pop it in the post for you.

Very kind of you Barry, I'll pm my address now :)

[Pigmy Pony]

You're up high so the T shape bit of wet string should be fine.

You're right Mart, but we are a bungalow surrounded by houses and trees. We almost have a clear line of sight to Winter Hill mast, so who knows?

Got these fellas 15 miles away

https://radiotoday.co.uk/wp-content/uploads/2018/06/Winter-Hill.png

[Firebottle]

Hi Steve, for the 'wet string' antenna made from bell wire the dimension you want for the top of the T is 1.5 metres end to end.

[Pigmy Pony]

Hi Steve, for the 'wet string' antenna made from bell wire the dimension you want for the top of the T is 1.5 metres end to end.

Cheers Alan, I've learned something there :) Now is that 1.5 metres the optimum length, or the minimum?

I may still use the 'indoor' aerial my mate gave me, though it is pig-ugly, whereas the wet string approach would actually be less visible.

Another question: can I attach the 'wet string' to an aerial 'plug' to go in that 75ohm socket (pictured), and do the cores of the wire have to be insulated from each other at the plug for it to work properly?

https://hi-fi-zone.com/wp-content/uploads/2018/11/SH105718-600x400.jpg

[Barry]

Most FM tuners cover the frequency range 88 - 108MHz. Thus taking a mid frequency of 98MHz the corresponding wavelength is approximately 3.06 metre, so a half wave dipole will have an end to end length of about 1.5 metre.

You can use 75 Ohm coaxial cable to connect to your tuner's coaxial input. The inner conductor is connected to one arm of the dipole, with the screen connected to the other arm.

[Andy831]

Following these explanations with interest and wonder, but also thinking if Steve is as confused as I am then maybe a quick sketch / picture might be worth a 1000 words :)

[Pigmy Pony]

Thanks to Barry's and Alan's information I do have a better understanding of what's going on... in the coming days I'll get to play about with it - I'm not worried about breaking anything, as this model of tuner regularly sells for just 30 quid or so.

When I bought my first house on the 80s I 'upgraded' from wet string to a proper aerial, and if I'm honest any improvement was lost on me. I think the place was a good reception area, or maybe I've just always had two cloth ears :)

[Mr.Ian]

I found a piece of copper pipe cut in half and joined together by a plastic T pipe connector works very well. ( as per Alan above 1.5m is a good general lengh or you can fine tune to your prefered radio station wave lengh - web search for the calaculation

Cover the pipe in 50mm wide white insulatioin tape to camaflage it if necessary

Clamp the outside shield of the 75ohm cable to one half and the internal core to the other half and IMPORTANT keep the down lead at 90 degrees to the pipe.

[Pigmy Pony]

Now that sounds proper, and written out in a way even I can follow :) Unfortunately it also sounds like it would be a bit industrial in appearance, even with the white tape applied, and unlikely to get past my resident arbiter of what looks right in home decor i.e. the missus :doh:

Life would be so much simpler if I had my own listening room... with a 70s serving hatch in the wall so she can pass me tea through :)

[Pigmy Pony]

Female/female coupler arrived this afternoon, thanks Barry. So I got the tuner up and running using that ugly antenna. Got a few stations (R1, 2, 3, Hits Radio and Smooth) with next to no background hiss. I'll have another play with it tomorrow, see if I can improve things, and get some more stations.

I ordered one of these yesterday, no idea how ell it'll work, but it was only a fiver.

https://www.ebay.co.uk/itm/332715794867

[Firebottle]

That should work well Steve, find out what polarisation is used on your local transmitter, vertical or horizontal.

Then orient the antenna the same for best signal.

[Pigmy Pony]

Hi Alan, just checked, and Winter Hill transmitter is horizontally polarised. And much closer than I first thought, about 5 miles as the crow flies. What does this mean for a 'wet string' aerial, should it be like an upright 'T', or on its side for best reception?

[Barry]

If the transmitter is horizontally polarised then your 'wet string' antenna should be orientated in the same sense, that is, as an upright 'T'.

[Barry]

Apropos your ribbon antenna, despite it being terminated with a Belling Lee plug, there will be an impedance mismatch when it is plugged into the 75 Ohm socket of your tuner. This is because the ribbon antenna is a folded dipole having an impedance of 300 Ohm.

If the radio signal from the Winter Hill transmitter is strong in your area, the mismatch loss of a couple of dB won't be a problem. If however the received signal is weak, there will be additional problems from signal reflection off items internal to the room as well as external. This because when the folded dipole ribbon antenna is mismatched to the receiver the ribbon downlead itself becomes an antenna. The only proper way of avoiding all these problems is to use a 300 Ohm to 75 Ohm balun, which is essentially a transformer having a turns ratio of 2:1.

As always, see how you get on with the ribbon antenna. It may well be sufficiently good for purpose.

(Suitable baluns are readily available, having a Belling - Lee plug on one side and two screw terminals for the ribbon cable on the other side. They are not expensive: https://www.ebay.co.uk/itm/236327971463?_trkparms=amclksrc%3DITM%26aid%3D1110 006%26algo%3DHOMESPLICE.SIM%26ao%3D1%26asc%3D29255 4%26meid%3Dded260e5bc1442e3affe94d89786c48b%26pid% 3D101224%26rk%3D1%26rkt%3D5%26sd%3D177129148144%26 itm%3D236327971463%26pmt%3D1%26noa%3D1%26pg%3D2332 490%26algv%3DDefaultOrganicWebV9BertRefreshRankerW ithCassiniEmbRecall%26brand%3DUnbranded&_trksid=p2332490.c101224.m-1 )

[Pigmy Pony]

Cheers Barry, I'm learning a lot this week! Though not a real understanding of what I'm learning, if that makes any sense. I noticed the mention of 300 ohm in the listing, but hoped that it wouldn't be an issue.

It has become something of interest to me now, so these contributions from yourself and others are a good thing, and no doubt will be helpful to a few other members too.

I will keep updating with my "progress", at least within the limits of my poor hearing and technical knowledge :)

[Pigmy Pony]

Is this something that would work Barry? Or is there something else you might recommend? At these kind of prices I don't mind trying stuff out.

https://www.google.com/aclk?sa=L&ai=DChsSEwjWpcihic2QAxXnlFAGHapVGB0YACICCAEQDRoCZG c&co=1&ase=2&gclid=Cj0KCQjwmYzIBhC6ARIsAHA3IkS_H7LGBmTJRkS750dY rW5TIqKYNoNH1LAzxlNi2iVenDfkz8qEJugaAj8iEALw_wcB&cce=2&category=acrcp_v1_32&sig=AOD64_1U0Vs8id4kxXS5f1Pw96dsYF4_pQ&ctype=5&q=&nis=4&ved=2ahUKEwjelcWhic2QAxXEdUEAHdZsFucQ9aACKAB6BAgHE GM&adurl=

[Barry]

Is this something that would work Barry? Or is there something else you might recommend? At these kind of prices I don't mind trying stuff out.

https://www.google.com/aclk?sa=L&ai=DChsSEwjWpcihic2QAxXnlFAGHapVGB0YACICCAEQDRoCZG c&co=1&ase=2&gclid=Cj0KCQjwmYzIBhC6ARIsAHA3IkS_H7LGBmTJRkS750dY rW5TIqKYNoNH1LAzxlNi2iVenDfkz8qEJugaAj8iEALw_wcB&cce=2&category=acrcp_v1_32&sig=AOD64_1U0Vs8id4kxXS5f1Pw96dsYF4_pQ&ctype=5&q=&nis=4&ved=2ahUKEwjelcWhic2QAxXEdUEAHdZsFucQ9aACKAB6BAgHE GM&adurl=

If it includes a 2:1 turns ratio transfoemer, then yes it will be perfect.

[Pigmy Pony]

If it includes a 2:1 turns ratio transfoemer, then yes it will be perfect.

If the purpose is to go down from 300 ohm to 75 ohm, should that not be 4:1, or is there something I'm missing here? Bear in mind that just 12 hours ago I'd never even heard the word 'balun' :doh:

I've had a look online with what you posted in mind, but it's just served to confuse me, and the (non existent) information on the .item I linked to doesn't have any helpful details.

[Firebottle]

The impedance ratio is the square of the turns ratio.

So a 2:1 turns ratio gives a 4:1 impedance ratio. 300:75 as required.

[Barry]

If the purpose is to go down from 300 ohm to 75 ohm, should that not be 4:1, or is there something I'm missing here? Bear in mind that just 12 hours ago I'd never even heard the word 'balun' :doh:

I've had a look online with what you posted in mind, but it's just served to confuse me, and the (non existent) information on the .item I linked to doesn't have any helpful details.

"Balun" is just a contraction of "balanced/unbalanced", and in this case simply comprises a miniature transformer having a turns ratio of 2:1. That is there are twice as many turns on the balanced side as there are on the unbalanced side.

[Pigmy Pony]

Thanks guys, that makes sense now.

The item I linked to does state that it goes from 300 ohm to 75 ohm, so is it safe to assume a turns ratio of 2:1 then? Also the 3 quid asking price does seem suspiciously cheap...

Edit: I've just seen Barry's additional information in post #19, thanks for that... looks like that cheapie balun would be ok then. I'll just order one, 'cheap as chips' doesn't even apply, a decent portion of chips would cost more these days.

[Pigmy Pony]

Some companies selling products online give me the right hump :steam: The one I linked to earlier (Cricklewood) were selling the balun for £2.50 (£3 quid with the VAT added). I had to jump through all these hoops registering with them (email address, password, name and address etc) before I could order it. Then right at the end, with debit card in hand, I finally learn that they are adding another £4.50 for postage! Making it £7.50. Why could they not state postage costs right at the start?

There are a lot of sellers doing it this way, it's a bloody con.

Sod that, got one off Ebay for £4 inc. postage.

[Barry]

What did you buy? Can you provide a link to the eBay listing?

[Pigmy Pony]

This one.

https://www.ebay.co.uk/itm/304050731395?_trkparms=amclksrc%3DITM%26aid%3D7770 08%26algo%3DPERSONAL.TOPIC%26ao%3D1%26asc%3D202504 17133020%26meid%3Dc2494017c6b441029b2041d304f272a9 %26pid%3D102726%26rk%3D1%26rkt%3D1%26itm%3D3040507 31395%26pmt%3D0%26noa%3D1%26pg%3D4375194%26algv%3D RecentlyViewedItemsV2WithMLRPboosterAndUpdatedFeat ures_BP%26brand%3DElectrovision&_trksid=p4375194.c102726.m162918

I'm currently listening to BBC R2, and the sound as it is is quite good. A bit muted at the higher frequencies, but not bad. Barely any background hiss. I'm sure it could be bettered though, and I'm hoping my imminent deliveries will bring about some improvements, including pulling in some more stations. We'll see.

[Barry]

That should be fine. All you have to do now is to cut off the B L plug from your ribbon antenna, cut back the centre separating strip about 15mm and then bare the ends of the two conductors so as to attach to the two screws. :)

[Pigmy Pony]

Yes that's what I was thinking - If I hadn't been so impetuous I could have bought a ribbon antenna with spade connectors instead of the BL plug and with the balun as a 'kit' for less money. But no big deal, I'll arrive at the same point just a couple of quid poorer, and I'm loving this learning stuff business :)

[Barry]

How are you getting on with reception using the ribbon T antenna - is it doing its job?

[Pigmy Pony]

Apologies Barry, only just seen your post - I took delivery of this Balun a week or so ago, but all the TV-related stuff I've been busy with has caused the tuner to take a back seat.

As it is right now, the tuner is doing a decent job, but later today I'll plumb this Balun thingy into it and see how that goes. Not sure what to expect, as I say it's already working pretty well, especially considering the budget nature of the tuner itself.

[Pigmy Pony]

I got that balun fitted to the end of the antenna, with help of an electrician's screwdriver and a handful of sausage fingers. I don't know what improvement would have been likely, but I have noticed a slight increase in volume for a given setting, but without an attendant increase in hiss (which was pretty negligible already to be fair).

So all in all I'm pretty pleased with how it all works, now I'll see how long before the novelty wears off, as my usual stations (Caroline and BBC 6 Music) aren't catered for on FM.

Still, a nice thing to have going while I'm pottering about the house, and I may even give Radio 3 a go :)

[Barry]

Good news then. Well done. :)

[Pigmy Pony]

Thanks again Barry, it was your advice that got it where it is :)