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A Big Fix That's Overdue

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A Big Fix That's Overdue

Medium Wave AM radio has its faults, but one that should have been fixed by now is the polar directivity of the signal which can discourage listeners needlessly.

Here's an example. This shelving unit here in the kitchen was custom built for this location... up top is a Panasonic table radio neatly set against the east wall. Some stations come in well, but others would require twisting the radio at a sloppy looking angle so the loop antenna in the back is favoring the north-east.

I happen to know how to swivel, turn and angle radios for best reception, but most people are unaware of it or are opposed to having their radio out of place.

We've got to start immediately to design antenna systems that will fill in the nulls and make AM radio optimize no matter which way the radio is pointing.

Engineers have gotten lazy after decades of success and now we stand to lose the AM legacy as stations disappear because radios are facing the wrong way!

No more slacking!

Aerials

The requirement by designers, not necessarily radio engineers, for compact sets without external connections resulted in the use of loopstick antennas which are compact but respond to the magnetic component of the radio signal field. Loopsticks are, as mentioned above, directional.

An aerial, which is just a wire responds to the electrical component of the field and tends to be almost non directional. Even rather short, 1 meter or so, aerials work fine for local reception. The disadvantage is that it is not possible to null out interference such as can be done with the loopsticks.

But, because we just can't tolerate those ugly wires sticking out of our receivers, we suffer from the effects Carl cited.

Maybe a solution is to use three loopsticks mutually orthogonal in AM receivers with a diversity receiving system.

Neil

There were some...

There were some radios with the ferrite rod outside the cabinet and rotatable so the radio stays in one position and you just turn the antenna. The ferrite rod was in a plastic housing....https://ca.images.search.yahoo.com/search/images;_ylt=A0SO81_2CLBXVgQAb8...

 maybe the lipsticks  would

 maybe the lipsticks  would have to would have to be configured in the shape of a cross or an X Type shape.

Progressive Rock (Album Rock, Deep Tracks), Classic Rock

http://thelegacy.shorturl.com

More Power for Hobby Broadcasters

http://the-initiative.boards.net/

Loopsticks and Lipsticks

They put loopstick on a pig and ran it for public office.

Meanwhile, we're considering criss-crossed lipstick as symbolic of the "New Radio Revolution".

Carl Blare

Something to Ponder

" ... Engineers have gotten lazy after decades of success and now we stand to lose the AM legacy as stations disappear because radios are facing the wrong way!  No more slacking!"

Most "AM legacy" receivers going back to the Golden Age of Radio 60+ years ago used internally-mounted receive antennas having the same directional receive characteristics as modern-day loopsticks.

Basket Weave

Regardin: "Most "AM legacy" receivers going back to the Golden Age of Radio 60+ years ago used internally-mounted receive antennas"

What do we know about those pre-ferrite antennas? As I recall they looked like flattened woven baskets.

Carl Blare

Reading/Understanding...

My post stated that those early receive antennas (which were/are another form of a loop antenna) had/have the same directional receiving characteristics as modern-day loopstick antennas.

Your "quote" from my post was incomplete.

 

Reason Why

I know: "Your "quote" from my post was incomplete."

Because I was only asking about that part of your statement.

Your bracketed remark answers my question: (which were/are another form of a loop antenna).

"Another form" of loop antenna is interesting.

Carl Blare

Easy fix

Get a radio that has an external antenna input and use an active type antenna.

They are omini directional and have usually a gain to them which would improve

reception range.

Hi Carl been along time since we talked.

 

Wire Loops

Yea, my first thought was "Heck, I've got radios going back to the 1930's with wire loop antennas affixed to their back covers". Same thing, directional, able to peak signal while nulling interference. Been this way since Tesla. The loopstick was the same concept, only smaller to fit in smaller radios without losing as much sensitivity.

I have a couple nice console radios from the 1940's that have wire loop antennas inside their cabinets inside oval cardboard tubes that are mounted upright in the cabinet and rotate inside the radio.  It wasn't too practical to rotate your 80 pound console radio in the  living room, but you could reach behind and spin the antenna.  

I have a General Electric "Super Beam-A-Scope" antenna of this style that I rescued from a scrapped console radio. Says right on it "Reduces Radio Interference". I'll have to post a photo of it.  I saved it from the old radio as it can of course be connected to any radio to improve reception.

Photo later. I'm off to work.

 

TIB

I Remember Them

Tim reminded me: "...wire loop antennas inside their cabinets inside oval cardboard tubes that are mounted upright in the cabinet and rotate inside the radio."

Yes, I'd almost forgotten the big cardboard tube in the lower rear of the radio... as a kid it was a curious but mysterious fixture right near where I learned never to touch wires connected to the electro-magnetic speaker!

Carl Blare

Just think if we can get the

Just think if we can get the FCC to crack down on these faulty AM recrivers what happens to part 15 Hobby Radio?  Increased range.  Isn't that what The New Radio Revolution wants?  Why not make this a part of the petition as well no?

Progressive Rock (Album Rock, Deep Tracks), Classic Rock

http://thelegacy.shorturl.com

More Power for Hobby Broadcasters

http://the-initiative.boards.net/

Crack down on receivers...

While I don't disagree with your intent.  I would not include that as part of the petition.  I would remain focussed on one area, succeed there, and move to another.

Trying to achieve greater coverage via Part 15 will be hard enough to accomplish without having to defend or justify to radio manufacturers why they should have to cater to what they are being to told is a dying band/mode.   That is supposing that the FCC accepts the proposal and it makes it to the stage of requesting comments from the public.

Then add to that, the group petitioning for change are Part 15 Hobbyists?  

my .02

 

 

Working on getting our small town of <4000 local programming.

Well Reasoned

CraigF is absolutely right about that... stick with one main objective in the "Petition" and aim all the effort toward that one subject.

Here is an additional thought ....

To get radios improved you don't need to talk to the fcc... speak straight to the radio manufacturers! They don't need FCC permission to improve antennas or other changes you might want... If they think you have a good suggestion they can go ahead and design better radios! The key point would be whether the public would purchase the new radios.

Carl Blare

Beam-A-Scope

I did promised a photo of a Beam-A-Scope, didn't I? This is a loop antenna inside an vintage console radio. You can see the wood dowel at the top, as well as the connectors for connecting to the radio set. It rotates on those dowels so you can get best reception. Fits inside the lower part of the console cabinet.  This is from a GE radio, but Crosley, Philco and all the rest had their own versions in their better console radios, especially if they included short wave bands.  Your radio could stay against the wall and you could reach behind and rotate the antenna.  This link should take you to the photo.

 

http://www.ironrangecountry.com/beamascope.jpeg

 

TIB

Beam a scope...

Thanks for the picture.  I have run across several styles of antennas in old radios I have worked on throughout the years, but not that one! 

Working on getting our small town of <4000 local programming.

Yard Waste Bag

That's what it looks like.

Carl Blare

Sack of Gold Medal flour owned by Frankenstein,

That was my first thought.

Sakrete, What they had to do to manufacture old products, right here in the USA.

AM BCB antennas

I have several Zenith Transoceanics that do just that. Place the wave magnet (BCB Loop antenna) in a small pinhole on the radio's handle then you just rotate the antenna not the whole radio. Another solution is to buy a small turntable or "Lazy Susan" at a place like Bed, Bath, and Beyond or similar store and sit the radio on that.

Jim Henry HBR Radio 1610, serving Honey Brook, PA. and NW Chester County.

Zenith Transoceanic

z

Jim Henry HBR Radio 1610, serving Honey Brook, PA. and NW Chester County.

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