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Deforest Loop Antenna Repro
https://antiqueradios.com/forums/viewtopic.php?f=1&t=395144
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Author:  Steven Olson [ Apr Wed 07, 2021 6:17 pm ]
Post subject:  Deforest Loop Antenna Repro

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Thought I'd show my reproduction Deforest loop antenna. I made this for the challenge and to introduce myself to SolidWorks. A person with a real antenna provided me tracings, measurements and photos. I found other dimensions and photos on this site as well. Disclaimer: I have never seen a real Deforest antenna in person so I'm sure there are details that are not correct, in particular details of the tap switch.

The wooden parts are walnut and milled with a CNC router. I believe the black center bracket originally was bakelite. I CNC milled my bracket from a "plastic like" material called Delrin. I purchased a sticker form radiolaguy and installed it in the center recess of the bracket. There are black pieces on the ends of the wooden sticks. Not sure what the original material was but I also milled these from Delrin.

The antenna is strung with wire I braided myself. The original was covered with two layers of silk wrapped in opposing directions. I intended to replicate the wire as best I could but I opted for expediency.

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Author:  palegreenthumb [ Apr Wed 07, 2021 6:56 pm ]
Post subject:  Re: Deforest Loop Antenna Repro

Wow, super nice!

I wish I had a workshop that would let me do work like that. Or the knowledge how to operate the equipment. I'm thinking of taking a course in "Fabrication" once the pandemic is over though... I want to learn how to use a milling machine, a welder, etc.

Great work! I really like it. What does the base look like? And... how do you braid insulation on wire?

Author:  egg [ Apr Wed 07, 2021 8:54 pm ]
Post subject:  Re: Deforest Loop Antenna Repro

Yes... super work... :)
I'll take a dozen!

Here's a neat German manufactured loop antenna that you may like. lol
viewtopic.php?p=2509328#p2509328

Greg.

Author:  John Bartley [ Apr Wed 07, 2021 10:00 pm ]
Post subject:  Re: Deforest Loop Antenna Repro

Steven Olson wrote:
Thought I'd show my reproduction Deforest loop antenna. I made this for the challenge and to introduce myself to SolidWorks. A person with a real antenna provided me tracings, measurements and photos.


Your work is superb. I love the attention to detail, right down to the decal. Nicely done !!

Author:  Robert Lozier [ Apr Wed 07, 2021 10:32 pm ]
Post subject:  Re: Deforest Loop Antenna Repro

You have a braiding machine? Tell me more!
Robert

Author:  atwaterkent1 [ Apr Thu 08, 2021 4:43 am ]
Post subject:  Re: Deforest Loop Antenna Repro

Excellent work Steve, very nice.

Author:  radioaddict [ Apr Thu 08, 2021 5:20 am ]
Post subject:  Re: Deforest Loop Antenna Repro

palegreenthumb wrote:
Wow, super nice!

I wish I had a workshop that would let me do work like that. Or the knowledge how to operate the equipment. I'm thinking of taking a course in "Fabrication" once the pandemic is over though... I want to learn how to use a milling machine, a welder, etc.

Great work! I really like it. What does the base look like? And... how do you braid insulation on wire?



The radio is the "base". The antenna plugs into the top of the cabinet via a hole in the top of the radio. For example, a DeForest D10.

Author:  Steven Olson [ Apr Thu 08, 2021 11:22 am ]
Post subject:  Re: Deforest Loop Antenna Repro

Robert Lozier wrote:
You have a braiding machine? Tell me more!
Robert


viewtopic.php?f=19&t=330308

Author:  Steven Olson [ Apr Thu 08, 2021 11:24 am ]
Post subject:  Re: Deforest Loop Antenna Repro

oops, didn't get the full path to the link

Robert Lozier wrote:
You have a braiding machine? Tell me more!
Robert


viewtopic.php?f=19&t=330308

Author:  black85vette [ Apr Thu 08, 2021 12:28 pm ]
Post subject:  Re: Deforest Loop Antenna Repro

I have made several loop antennas but none of them reproductions of vintage loops and none as nice looking as yours. I also have machine equipment in my shop. Having metal working equipment is pretty useful in restoring old equipment like your braiding machine and for fabricating. I do no have any CNC in my shop. Everything is manual.

Very nice work!

Author:  Steven Olson [ Apr Thu 08, 2021 1:05 pm ]
Post subject:  Re: Deforest Loop Antenna Repro

black85vette wrote:
I have made several loop antennas but none of them reproductions of vintage loops and none as nice looking as yours. I also have machine equipment in my shop. Having metal working equipment is pretty useful in restoring old equipment like your braiding machine and for fabricating. I do no have any CNC in my shop. Everything is manual.

Very nice work!


The CNC machines opened up a whole world of possibilities for me. Unfortunately I don't have one either but within a mile from me is a facility that has a complete wood working shop which includes the CNC machine i used, metal shop, electronics shop and more. I pay a flat monthly fee for access to these tools. I have toyed with obtaining my own CNC machine but the cost to get anything of a decent size would pay for several years of monthly fees at this facility I use.

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