Magic Loop Antenna Idea - Advice?
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I don't have space for a long wire antenna and not versed enough to know the best alternative. I just need an antenna I can use for both regular listening on one of my consoles, and simple testing for others I'm working on. I picked up a RCA 12"x12" mountable "Magic Loop" antenna in an auction and pretty cheaply. It looks pretty cool and is in great shape. I was thinking I could mount it in a good place and maybe rig it with a more universal connection for swapping out radios.
If in good operating condition, is this type antenna any good? If so, is it feasible to change the wires/connections to work with my single post antenna connections? It has 3 wires coming off the antenna and soldered onto connections on a bakelite block, then a multi-wire strap coming off the block ending with a 5-pin flat connector.
I know I could find a much better antenna, but am curious to try this unless these just don't work well. Any advice would be appreciated.
"Ignorance is bliss...'til you have to fix a radio..."
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Give it a try. If its used with a radio which it is not designed for its simply a long piece of wire wound up in a coil electrically. You could probably unwind it and get better reception!
General rule of thumb about old radio "antennas" like the ones on the back cover of a radio or in the bottom of a console. They are usually part of an tuned circuit internal to the radio simply exposed to 'open air' for reception. Not an 'antenna' per se in the same sense as say a TV antenna.
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Okay, that makes sense - I understand. I'll try it and see if it works. I'm sure I can always keep an eye out and flip it to someone who might can use if it doesn't work. Thank you for the info, I obviously still have a lot to learn on the electronics...
"Ignorance is bliss...'til you have to fix a radio..."
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check the Bar & Grill area on this website. I started a thread there on " building your own tuned loop antennas" that work with any vintage radio! Photos there as well. These antennas WORK!!!
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Hey Texasrocker,
Thanks for responding. I actually had read your thread in the Bar & Grill and, well, I'm just going to say it -- I completely understand how to construct the antenna from a wood and winding standpoint, but feel too technically ignorant to understand the part about the addition of a proper tuning condensor, correct terminal strip connection, adjusting the condensor to match up with the radio's, etc, etc... I understand the concept and why for each aspect, but shy'd away from tackling it - enen though I'd like to. Can it be any condensor off any old radio? Same question about the terminal strip.
I'd really like to build one of these and maybe should just jump in and tackle it. I tend to worry a little too much about making mistakes...
"Ignorance is bliss...'til you have to fix a radio..."
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if you want a really cheap alternative i use slinkies,you can hang them from a hook on the ceiling,pushpin in the wall or string them out on the floor along a wall,they work very well.
phil
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Hello Jayyoungs. My loop antenna-design is alot simpler than you would imagine! Yes, the tuning condenser used on the frame can be stripped from any spare parts AM radio chassis. Once you take time to build the wood frame, wrap 18 turns of wire around it, I can help explain in detail how to add the cntr-coil, & coax lead. Very simple!! Building the 2' x 2' wood frame, and wrapping the long wire around the outside of frame is the hardest part.( wears out your wrists, but very tolerable going slow making the 18 turns in one go)! If you have a spare a.m. radio parts chassis with a 2-gang tuner you can use, plenty of solid-strand 18 ga wire ( approx 140' on a roll), dont let this project intimidate you at all. I can help walk you thru this construction easily! Having this type tuned-loop will completely eliminate your needs of a outdoor longwire antenna forever.This antenna can be used with ANY Radio, TRFs, superhets, & portables. You can use 1" x 2" pcs of wood for the frame. 1, - 8' pc 1x2 straight lumber from Lowes will yield all your special cut pcs of wood needed for the frame. You will need a few handtools such as a coping-saw or better yet a handheld elec sabre-saw makes building the frame abit easier, drill with small drillbit, woodglue,etc. In any case, I will be happy to help you anyway I can! Once you build your first, the others you build is a "breeze"!! I recently helped a fella via a couple phone calls complete his. He was equally amazed at the performance of the antenna!! If you decide to build one, just pm me. I will be glad to provide easy to use instructions! Sincerely, Randal
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For anyone who reads this post -- Texasrocker's "Tuned Loop Antenna" posted in the Bar & Grill is fantastic. Anyone who needs a great antenna should build one of these. I built one this weekend and it is AMAZING how well it works. And, it is very easy to build -- my being able to build one is proof of that fact. ![Icon_smile Icon_smile](https://philcoradio.com/phorum/images/smilies/icon_smile.gif) I owe a big thanks to Texasrocker who was gracious enough to answer all my questions.
The antenna works extremely well. I have it attached to a big 9-tube Zenith console that has a tuning eye. The radio now picks up stations that it never could touch before. An example: I can pick up a station with a signal filling about 2/3 of the green tuning eye, then tweak the antenna condenser to match and - WHAM - I'm at 100% full signal strength with great clarity!
I've attached a few pictures of my antenna. I wanted it to really look nice and be a fixture with my radios, so I stained it with dark walnut Minwax, then applied a few coats of Van Dyke Brown lacquer. I still have the clear lacquer to go, but think it already looks pretty good.
Very cool and fun project!
"Ignorance is bliss...'til you have to fix a radio..."
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That is a nice antenna - good work!
The problem is the need to adjust the variable capacitor on the antenna, especially if you want to sell the radio or give it as a gift.
Does anyone have any ideas on how to make an antenna which either does not need any such adjustments, or which adjusts automatically with some sort of circuit (does not have to be tubes)?
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FStephenMasek Wrote:That is a nice antenna - good work!
The problem is the need to adjust the variable capacitor on the antenna, especially if you want to sell the radio or give it as a gift.
Does anyone have any ideas on how to make an antenna which either does not need any such adjustments, or which adjusts automatically with some sort of circuit (does not have to be tubes)? There are ways to make one without the variable capacitor, but the tunable antenna will provide better performance. That is why the AM antennas for sale, such as the Select-A-Tenna have tuning controls. If you are looking to make the antenna for yourself, you should go with the tunable one. If you decide to later sell or give away the radio, you can keep the tunable antenna and make a similar loop without the variable capacitor.
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Hi Stephen,
Thanks for the compliment. I'm sure there are aspects I could have done better, but it was a fun project and I'll be making more of them. Texasrocker on the Phorum helped ensure I didn't screw it up too badly!
I agree with Scooby. I've tried several types of antennas (short of stringing a true long wire that I don't have space for) and this tuned loop is many times better than anything else I've tried. I had the same concerns as you, but figure most radios for sale either have an antenna built in or don't include one at all. The tuning aspect of the antenna actually adds more fun to the experience. Rather than simply tuning with the radio knob, it's great to hear the antenna lock in tight on a station you could faintly hear otherwise.
Anyway, good luck - happy to answer any questions if you have them.
Joe
"Ignorance is bliss...'til you have to fix a radio..."
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