Dipole Antenna what is it. What it do. How it work

[46conehead]

Hi all
This antenna has been hanging around here for quite some time. We know it's a dipole antenna but what's the can in the center. The rubber nub on top has PHILCO embossed on it and physically separates the two dipole halves. The can was half full of tar covering the components. I melted the tar and got the innards out. The guts are two stacked metal donuts, probably coils as there are leads going to them. Me thinks that's a resistor or maybe a capacitor across the down leads. What's really strange, only one side of the dipole was connected to the components. There was no evidence of a lead ever existing and being attached to the other half.
Anyway… Anybody know what it do, how it work? : Anybody?
Mike

[Texasrocker]

Welcome 46conehead! You have a very interesting dipole antenna indeed! Me thinks it is original Philco accessory item part # A- XXX outdoor FM antenna kit with one side going to ground (missing)in case of lightning strikes. In the case of your antenna innerds, looks like it has already been struck by lightning! I wouldn't worry about finding a replacement. I would be worried if you inhaled any the tar fumes when melting though! (J.K.!) I will say, install all new capacitors & resistors ( just to be on the safe side) fly it up in the air again with the insulators, and enjoy FM reception from 88-108 mhz on your favorite fm receiver!! Enjoy!! ( Ron will be here later to splain' what you got )
ol, Tex

[exray]

It looks much too long to be an FM dipole. I suspect it was for shortwave and the gizmo is/was some sort of matching transformer. My guess is that both sides were connected and one connection may have disappeared because of lightning.

[46conehead]

Hey guys thanks for the input
It may look burnt, like it was hit by lighting, but that cause it was submerged the tar. The tar was not only the weather proofing but also held the innards in the can. Double checked it again and nope no evidence, burnt, broken or busted, at all of a second lead.

Added note there is a solder terminal on the lower fiber disc. It's connected to the upper disc by the bare wire to the same terminal as the dingy white wire. So that's 3 leads out the bottom.
Anyway I'll just put it back together, using epoxy (not tar), play with the leads and see what it does.

Thanks all,
Mike

[codefox1]

No, actually it was an early stereo lightening powered battery charger.

[Texasrocker]

OK Ron & Chuck,.... it's your turn to help figure out this vintage Philco "mystery" antenna is. (hee hee)
ol, Tex.

[Ron Ramirez]

Exray already answered the question.

[46conehead]

Hi Ho!
Found the answer (for what it's worth). The antenna is a "Philco All-Wave Aerial". That can is a Balun.

[Sparks_Radio]

Yes it is called an antenna matcher or Balun. One side that isn't connected could be the counterpoise. The counterpoise is actually an artificial ground. It does seem funny that there is a missing connection, but as was mentioned lightning may be the culprit. The reason for matching is to make the transfer of the RF signal through a balanced lead line. It reduces the loss or attenuation of the incoming signal. (Some one may have used it hooked up to a transmitter and tried to use it that way and burned out one side because of the power used to transmit) The design of the dipole is to string it up to a tree or pole(s) as high as one can get. The higher the antenna the more gain of signal. The antenna is positioned to receive the shortwave broadcasts most interested in, such as Europe, or far-east, or South America or Africa.
The signals that Hit the antenna are electrical in nature and when they hit the wire create an electrical voltage, which in turn travel down to the radio and the radio amplifies the signal and separates the RF portion and audio.
Look at this link:
http://www.philcorepairbench.com/mystery/40-6112.htm

[46conehead]

Well, I determined the balun is undamaged. I put the balun back together using silicone in place of the tar. It's an offset antenna. One side is 50' long and electrically connected to the balun. The other side is 17" and not electrically connected to the balun. There are 3 connections on the bottom of the balun (call 'em 1,2 & 3). 1 & 2 are jumped together (inside the balun) then connected to the donut coil. The #3 lead, the other coil and the antenna lead is connected somewhere in the donut coil . I surmise the #1 is for the ground connection and #2 for one conductor of the twisted pair. #3 is the "antenna" wire of the twisted down lead.
The twisted pair down lead is rotten so I've replaced it with RG6 coax. Shielded side to the #2 and center conductor to #3. Also ran a #16 gauge ground wire to #1.
Mounted the dipole tween the 10' antenna pole on the house and a tree. It's about 22' above the ground.
I haven't connected it to the radio yet. We'll then see how it compares to my existing 35' dipole (as soon as I get my Philco up and working).