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I have a Roberts Blutune 50 which is generally in good working order, but all it has as an antenna is a piddly wee wire snaking out the back - I reckon it to be about .8mm or thereabouts. Unfortunately when moving the antenna snapped off at the back. I decided to open the unit up to check if I could extend the antenna, but I didn't really see what I expected from most guides and tutorials for fixing antenna.

All I have is that single wire (with not much length, since it broke off fairly close to the contact) and I can also see a very similar wire connected to either the same or a very close contact which is clipped to a metal panel on the back of the radio. I assumed this was something grounding, but perhaps it is relating to the signal?

The guides and tutorials I'm seeing all seem to reference multiple wire ends to extend and things like, that, but all I have is this single wire. What am I to do?

EDIT: for extra info.

I'm afraid I don't know how long the original antenna was - if I had to estimate, probably about 3-5 feet?

Here are a couple of images:

Two wires In this one you can see the two wires: the one with a clip to the back of the unit, and the other with the broken end (which I have stripped back some).

Stripped wire and wire affixed to back In this one you can see the way that the second wire attaches to the back of the unit, specifically the metal plate that spans the back of the unit.

After a little more digging, I think my next step is to find a length of wire and attach it to the broken end. I'm not sure of the exact details of this (length, material or thickness of wire?) so any contrary or supplementary advice is appreciated.

(I also appreciate the meta-issue with this question, as pointed out in the comments, so am very grateful for any allowance for continued assistance.)

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    Could you share a/some picture(s)?
    – Dieter Vansteenwegen ON4DD
    Commented May 24, 2020 at 18:25
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    From the pictuees/info I find online this looks like a basic fm/dab radio, with a single wire as antenna, so it shouldn't be too complicated to replace it. A good picture would help to understand what th second wire may be...
    – Dieter Vansteenwegen ON4DD
    Commented May 24, 2020 at 18:31
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    ham.stackexchange.com/help/on-topic says that questions pertaining to consumer and broadcast radio are explicitly off-topic here. Repair questions on consumer electronics are also explicitly off-topic on electronics.Stackexchange.
    – Marcus Müller
    Commented May 25, 2020 at 16:38
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    @MarcusMüller In my understanding of our scope, repairing a receiver, regardless of the operating band, is certainly on-topic here. (Particularly when the matter is as non-application-specific as the antenna connection.) That said, a picture would be very helpful to actually answering the question.
    – Kevin Reid
    Commented May 25, 2020 at 18:20
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    @MarcusMüller Hm, I see what you mean about the page. Perhaps there should be a meta question about clarifying the scope or the wording a bit (let's not discuss it further in these comments).
    – Kevin Reid
    Commented May 25, 2020 at 21:18

1 Answer 1

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Increase the length of the "antenna" by baring the lead of a longer wire and twisting the bare leads of the two wires together to make a splice. Use a similar gauge and material for the antenna extension. Most any wire is suitable. Simple, insulated "hook-up" wire is a generic name for a useable kind of wire. It can be single or multi-strand conductor for such a non-critical application. The length is more critical than the gauge in this application.

Finally, use a Western Union Splice to make a clean noise-free connection.

The length of the antenna can be calculated using online sources for the specific radio bandwidth. Using this calculator, 52 inches was found appropriate for an FM band radio (half-wave) antenna having 108 MHz maximum frequency.

Failing that, contact the Roberts Co. directly for their recommendation for an antenna length.

Good luck.

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  • This is very helpful, thank you! I don't have the original wire to splice, it was lost in transit - are you aware of what alternative I should be using, or what I would need to know in order to find out for myself?
    – Jack Parkinson
    Commented May 28, 2020 at 16:22
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    This is not very helpful, because it ignores the fact that an antenna is not a telephone cable, and a twisted splice probably means a lot of inductance, effectively shortening the antenna
    – Marcus Müller
    Commented May 30, 2020 at 0:17
  • @marcusmuller A lot of inductance? are you sure? I think of all the radio (receiving) antennas I've made from steel wire clothes hangars... The only issue I see is "52 inches" when I believe 26" would be better (counterpoise seems present) however 52" should still work fine.
    – Chris K8NVH
    Commented Jun 11, 2020 at 2:51

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