Mounting a Radio Shack Scanner Discone Antenna???

[mfred]

A friend of mine gave me a slightly used RS Outdoor Scanner/Ham Discone Antenna Catalog # 20-043. My question is can I eliminate the large rods that connect to the antenna and just keep the small rods? The antenna looks a bit much on my house and I’m trying to scale it down a bit. Will the antenna work descent without the large rods? I primarily listen to VHF and UHF and 800MHZ. There are some low band systems as well. What do these long rods pick up?

Thanks,
Mark

 

[TeRayCodA]

Short answer:NO
These are an essential part of the "discone"I'm assuming you are referring to the Conical elements?Longer elements?

 

[mfred]

Yes, the longer stainless steel rods that connects to the middle of the antenna and angle down and out. I don’t understand the technology or the construction of this antenna, but I’m assuming if I removed these long rods, my reception would be better than the stock antenna on my BC780XLT? Then there’s the whole thing about putting it in the attic???

 

[TeRayCodA]

Actually,if I remember correctly(everyone correct me if I'm wrong,as many of these I have built, I should know this!)but the cone elements act as a ground/reflector for the disc elelments.

Removing these,you will have a disc,even worse,a horizontally polarized antenna.If you feel inclined to experiment,after all,that's what makes this hobby fun,but I don't think you'll be pleased with the reception.

Yes,it probably would pick up more than the stock antenna,but so will a random length of wire pushed into the center of the BNC socket.

But,yeah,they put the cone elements there for a reason.

Also,the angle.60 degrees seems to be the "magic"number.-That's what I build mine at,and they perform well.

 

[TeRayCodA]

Keep in mind,that putting it in the attic,reception will be marginal,as the roofing will give a certain amount of attenuation.

Some have no other choice than to attic mount an antenna,because of certain neihborhood outdoor antenna restrictions.

Best if you can get it as high and in the clear as practical/safe.
Good luck.

 

[Al42]

Actually,if I remember correctly(everyone correct me if I'm wrong,as many of these I have built

I'm never one to pass up an invitation.

but the cone elements act as a ground/reflector for the disc elelments.

Ground or counterpoise.

Also,the angle.60 degrees seems to be the "magic"number.-That's what I build mine at,and they perform well.

The angle determines the impedence.

Bottom line - depending on the frequency, without the "bottom rods" it may perform worse or a little better than a short (like a few inches) piece of wire. Add (or, rather, subtract) the cable loss and you're right - sticking a random length of wire into the antenna jack would probably be better.