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Graham J Samuels
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AM Antenna

Maybe one of you can help , Last week I got a 1938 Westinghouse 566 radio , When I bought it the sales guy said he did not know if it worked, The person who had owned it never returned and that was at least 20 years ago , So we took her to his test bench and he removed the back , Slowly he brought the voltage up , the tubes came to life and wonder of all she started to play and very weird it was playing the music from that tyme , Well I just had to have her . He said he did not want me to take it now that he wanted to test it for a while to make sure it does not burn my dig down and put a new power cable on it as the original was in a dangerouse condition ,Rubber and bakeolite does not last this long. We agreed on a price and based on the relitive knowlege of these I felt I was getting a deal. Fast forward I get a call from Ring Audio your machine is ready Great Ill be down now , Driving along Queen St I see a parking spot right in front of the store put my flashers on go in and he has the radio on the bench turns her on a few min the tubes warm and she sounds just fine , He tells me I may have to add some sort of antenna as this was not the best but play with it and enjoy , I walk out to find a parking fool drawing up a ticket for me Rather than calling him some rude names which he proly deserves I just smiled and put my 566 on the pass seat strapped her in and drove off to old radio land . Now here is the Q What type of extra Am antenna can I rig into this ? She does pull in a few stations but very weak and if I move it she will loose them Any ideas ?

JIMV
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Try this

I know...the Shack...but these types of AM antenna's really work and are tunable

http://www.radioshack.com/product/index.jsp?productId=2405978&filterName...

Graham J Samuels
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re am

Thanks for the tip , I went into a Radio Shack last week the wrong one as the guy did not know what to recomend , Will try another store, This is what Im looking for , let you know if this works , Cheers !

absolutepitch
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AM Antenna

Since AM is 530-1600 KHz, or around 0.5 to 1.6 MHz, the wavelength is on the order of 300 meters or about 1000 feet. An antenna should be equivalent to the wavelength or some fraction thereof.

The antenna on a car receives FM and AM and it's only about 3 feet long. A fraction of the 1000 feet should work, like 1/2, 1/4, etc. Practically, 1/100 may work (10 feet), such as a long length of wire indoors. Be careful outdoors because the antenna needs to be properly grounded, and I do not know all that needs to be done to be safe.

Good luck.

Graham J Samuels
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re Am

Thanks for the info , Yeah I was going to run a wire but did not know how long , If the Radio Shack unit does not work will try this . Also will the gauge of wire sheilded or non effect the reception? This is going to be an indoor set up.

absolutepitch
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AM antenna wire

Shielded wire would not make sense to me, because shielding is to reduce radio frequency interference or pickup on audio cables. A length of insulated single wire should work.

When I was a kid, and not knowing much about electronics, I took bare wire, wound it around a 6-foot 1x2 with the loops 1-inch apart, and hooked one end to an AM receiver breadboarded. It sounded 'good' through a cheap one-ear ear-phone. Not suggesting you actually do this - just an interesting sidebit. It seems like almost any single wire will work.

I hope the electrical engineers out there will chime in to provide more useful information than I have.

[Edited to correct spelling on 4-21-11]

j_j
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Long wire antenna

If you run one, do NOT forget to properly lightning-protect it.

Graham J Samuels
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Antenna

Ok so I tried several wires and no great luck , A pal said why dont you just take a wire and go into the ground pin of your electrical outlet there by using your buildings ground as your antenna , Wonders of all it worked now I have signal strength. the 556 pulls in stations clear and without much drift although it is an old radio and one still has to dial in the station with a bit of finess but now I can enjoy my old tube finaly.

absolutepitch
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Antenna into outlet ground

Usually you do not want to ground the antenna signal. Also, I'd be very careful and ask an electronics expert. If you don't have a filter in line with your antenna, you may get AC current from power line if somewhere else in that house circuit there occurs a short to ground.

Graham J Samuels
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re Antenna

Yes your right I had this set up and although it seemed to work every tyme the furnace kicked in the ac noise was there, So I went back to the single wire from the radio 10 ft up to the top of the window this is a bit better ,though not as good as I would like it at least no ac noise is present , Thanks for your repy.

Dr. Spivey
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AM antenna

Here's a treatise on the basics of AM antennas. http://www.hard-core-dx.com/nordicdx/antenna/loop/amloop.html

Here are some decent antennas you can purchase: http://www.universal-radio.com/catalog/mwant.html.

Look around both of those sites, there is a ton of information available.

To a radio hobbyist, AM radio refers to any frequency from "DC to Daylight". Medium wave is the broadcast band. So, "am medium wave antenna" would be the term to enter into your search engine, resulting in a wealth of information.

A simple home made or purchased loop antenna will serve your needs.
Have fun!

Graham J Samuels
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re AM Ant

Thanks for the links , Very interesting lots to choose from , Amplified or not ? Some have said for  my kind of radio a non amp would be right  , Thus the Grundig AN200 looks like a good unit if this is correct , My 556 has just a loop ant no fer bar so I wonder if this has an effect on the amplified or not issue ? Given that the prices of these are ( not expensive} I want to make sure I making the right choice .

pentode
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AM is fairly forgiving and, I

AM is fairly forgiving and, I believe, the longer the wire the better.  You may "tune" the length to wring the last bit of signal, however. Using an insulator on each end, a 20" - 30" wire up in the attic should suffice. You may use a shielded or unshieled "down"  lead to the radio.  A genuine grounding of the chassis often results in better reception as it "completes" the tuning circuit for a stronger RF signal.

Loop antennas are usually part of the tuned RF circuit, but long-wire connections are often also available on those radios.  Good luck!

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