General Forum

Re: BeoMaster 1000 - which / what aerial to use?

Craig — Fri, 18 Jun 2010 12:09:26 GMT

Ooopps forgot that the black ones use a different conection. Good news is though I have one sat in front of me. Guy, drop me a PM with your address and ill pop it in the post for you tomorrow.

Craig

Re: BeoMaster 1000 - which / what aerial to use?

tournedos — Fri, 18 Jun 2010 11:23:41 GMT

Large48:

Yes it has the two small rectangular connectors, as opposed to the round ones.

So a bit of wire in each one might work? or just one bit of wire in one?

:-s

Try with one first (it might work better in one or the other socket hole). If it works well enough for the stations you want to listen, problem solved!

If not, see my other post above.

Re: BeoMaster 1000 - which / what aerial to use?

tournedos — Fri, 18 Jun 2010 11:21:21 GMT

That was indeed the way you should've constructed an AM antenna in those days if you wanted good reception of distant stations. The problem nowadays is that in town areas there are so many electrical & electronic appliances running all the time creating interference that a "real" antenna can actually be worse than the simple wire setup.

However, I believe Guy was actually looking for an FM antenna. Most ready made FM antennas nowadays have been designed for 75 ohm feed impedance, which assumes the round IEC type RF connector in the receiver. The old receivers (just as these Beomasters) only have a connector for a 300 ohm antenna feed (two pins side by side), while starting from the '70s they may have both.

So, if the simple wire solution still doesn't give adequate reception, here's how you can construct a proper 300 ohm FM antenna. See for example this page and scroll to the bottom section ("folded dipole antenna"). To save you from all the theory, half wavelength on 88-108 MHz is three meters on average, and so the horizontal part in the picture needs to be 1.5 meters long. You can make the feed part as long as you need. Optimally you should use 300 ohm flat twin wire, but a suitably thin speaker wire works well enough.

Now, all that remains is the connector problem, since we only have the bare wire ends at hand. Can you guess what I recommend you do with them?

Re: BeoMaster 1000 - which / what aerial to use?

Large48 — Fri, 18 Jun 2010 11:16:31 GMT

Yes it has the two small rectangular connectors, as opposed to the round ones.

So a bit of wire in each one might work? or just one bit of wire in one?

:-s

Re: BeoMaster 1000 - which / what aerial to use?

vikinger — Fri, 18 Jun 2010 10:21:41 GMT

Seem to recall that the official B&O instructions that came with my BM1200 recommended a very long external AM antenna across the garden with ceramic insulators at each end. I recall trying this but it pulled-in too many distant stations and phenomenal background interference. A relative who was an electronics and amateur radio expert took one look at it and told me to replace it with a short wire as recommended above by Mika! (That same relative also swore by short pieces of wire for television reception: not sure that that approach would work these days with digital reception!)

Graham

Re: BeoMaster 1000 - which / what aerial to use?

tournedos — Fri, 18 Jun 2010 08:35:55 GMT

The later BM1000's won't have that old-old connector anymore, just a plain old one At least my black key BM1000 has antenna connectors which accept a small rectangular plug (two per connector) instead of those bigger round banana plugs.

Re: BeoMaster 1000 - which / what aerial to use?

Craig — Fri, 18 Jun 2010 08:20:10 GMT

Guy, you will find that banana plugs fit perfectly. Had the same problem with my Beomaster 900. These would be perfect, the ones I used were a bit to big in the body part and touched together. Had to put a piece of cardbord between the to insulate them. Then you can just use a normal FM aeriel.

Craig

Re: BeoMaster 1000 - which / what aerial to use?

tournedos — Fri, 18 Jun 2010 05:50:40 GMT

I always just recommend to just stick a piece of wire into the socket and hide it behind the shelf, but it never seems to catch on...

The problem is that I don't think the correct connectors are being made anymore, so you'll need to source them more or less directly from somebody's junk box. If you have a ready made FM aerial you'd like to use but it has the round connector (it's called IEC), you could snip the plug off and do the step 1 above with the center conductor and the sleeve separately. Impedance matching will be incorrect but it'll still perform well.

Regarding the stereo decoder, I believe the only certain way of knowing without a look inside is to hear it playing in stereo!

BeoMaster 1000 - which / what aerial to use?

Large48 — Fri, 18 Jun 2010 05:26:06 GMT

Hi all,

Just got a BM1000 for the first time (later black key one) and having looked at the aerial socket I'm a bit stumped.

The previous owner has tried to force an AM aerial into the two small sockets in the plastic which is a shame and all my other aerials are the round UHF(?) type.

Any ideas on what I need?

Also is there any easy one (apart from it showing) that the FM stereo decoder option might be fitted?

Cheers