| Author |
Message |
    
Timebomb
Junior Member
Username: Timebomb
Post Number: 45
Registered: 2-2005
| | Posted on Monday, May 09, 2005 - 7:59 pm: | 
|
I just recently found an old aluminum vertical telescopic antenna in pretty decent shape. The 4 radiator elements extend to about 18 ft. It would have three ground radials, they are missing, but where they mount is intact. To match, the very top piece has 3 "top hat" radials, but they do not look like the standard kind that just stick out. They are more or less in the shape of a diamond, and connect to the side of top vertical(4th) element:
/\
|| Imagine the lines connecting.
\/
I did some research, and thought maybe this is the Hygain CLR2, but the top radials are different. Does anybody know what antenna this is?
Also a few more questions. I'm thinking this is a half-wave antenna. Would it be possible to add an element in the correct size to make the radiator long enough to change into a 5/8 wave? I also need to know the length the ground radials are supposed to be, for either half-wave, and/or 5/8 wave. Here is a link with some good info regarding this topic:
http://www.copperelectronics.com/discus4/messages/14/39530.html
I just figured this is a good way to learn more about cb antennas while my Antron still stays tree top tall! Thanks in advance for any help. |
Bruce
Senior Member
Username: Bruce
Post Number: 2574
Registered: 9-2003
| | Posted on Monday, May 09, 2005 - 8:26 pm: |
|
clr2 sounds right |
Rfchallenged
New member
Username: Rfchallenged
Post Number: 4
Registered: 1-2004
| | Posted on Monday, May 09, 2005 - 9:15 pm: |
|
No, it's not a Hy-Gain CLR-2. Sounds more like an Antenna Specialist Mini Magnum II. They utilized 4 radials that were shortened with the use of small loading coils. And used the diamond shaped static loops at the top of the radiator. |
Timebomb
Junior Member
Username: Timebomb
Post Number: 46
Registered: 2-2005
| | Posted on Tuesday, May 10, 2005 - 4:20 pm: |
|
Rfchallenged, would the loading coils be located in the base section? Would that make it a 5/8 wave?
Also, does anybody know the length the 3 ground radials are supposed to be? I plan on replacing them since they are missing. Is there a formula for the length of the ground radials according to length of radiator?
Any info is much appreciated. |
Rfchallenged
New member
Username: Rfchallenged
Post Number: 5
Registered: 1-2004
| | Posted on Tuesday, May 10, 2005 - 5:53 pm: |
|
No. The A/S Mini Magnum used the coils near the center of each radial. It was a 1/2 antenna. If you were to fabricate radials from tubing they would need to be approx. 8.5 feet long I'm guessing, 1/4wavelength. |
Timebomb
Junior Member
Username: Timebomb
Post Number: 47
Registered: 2-2005
| | Posted on Tuesday, May 10, 2005 - 7:17 pm: |
|
hmmmmm....well there definitely aren't any coils on the antenna I've got. Any other ideas?? |
Bigbob
Senior Member
Username: Bigbob
Post Number: 1871
Registered: 12-2001
| | Posted on Tuesday, May 10, 2005 - 9:38 pm: |
|
Timebomb,the coils would be on the ground radials that you said are missing,the idea with the coils is to place them in the middle of the radials so they can be shortened to save space,it also narrows the bandwidth.Bigbob |
Marconi
Intermediate Member
Username: Marconi
Post Number: 425
Registered: 11-2001
| | Posted on Tuesday, May 10, 2005 - 10:56 pm: |
|
Since it only has three GP radials it sounds like a CLR 2 to me also.
AS did make a 18' Mighty Mag III that I know of and it did use a cap like mentioned above. It did have loads on the GP elements out towards the ends of the alum with wire tips making the rest of the 60" shortened length for the GP elements. I believe these tips were sort of like those on a Moonraker.
It probably used a small coil in the base near the SO-239 insulator for the radiator that sat at the bottom of the mounting bracket like a CLR2. May have had a copper wire coil or a small foil disc coil inside the bottom insulator to match the antenna.
There should be an insulator up at the top of the mouning bracket near the GP attachment brackets also.
I don't think this antenna never really got off the ground and popular. |
Timebomb
Junior Member
Username: Timebomb
Post Number: 49
Registered: 2-2005
| | Posted on Wednesday, May 11, 2005 - 2:39 am: |
|
Here's a pic of the base.
 |
Tech291
Moderator
Username: Tech291
Post Number: 174
Registered: 11-2004
| | Posted on Wednesday, May 11, 2005 - 1:53 pm: |
|
radio shack 1/2 wave.ground radials are about 39 inches long
tech291
CEF#291
kc8zpj |
Timebomb
Member
Username: Timebomb
Post Number: 50
Registered: 2-2005
| | Posted on Wednesday, May 11, 2005 - 2:28 pm: |
|
It HAD to be a rat shack antenna. Oh well! Could it be worth converting it to a 5/8? Is it possible? Figure I've got the backbone of the antenna, I could just adjust the length's, right??? |
Tech291
Moderator
Username: Tech291
Post Number: 175
Registered: 11-2004
| | Posted on Wednesday, May 11, 2005 - 3:23 pm: |
|
Timebomb,
If you were to open the bottom insulator,you would find the impedance match encased in an epoxy material.without retuning it,the conversion would hardly be worth the effort.
tech291
CEF#291
kc8zpj |
Tinker91
New member
Username: Tinker91
Post Number: 6
Registered: 2-2005
| | Posted on Wednesday, May 11, 2005 - 10:08 pm: |
|
I have one. it is a Radio Shack 1/2 wave. Ground radials are 48 in long with no coils. I bought this one when Radio Shack was selling Radio's.
Hope this helps.
Dave
Tinker
CEF 525 |
Marconi
Intermediate Member
Username: Marconi
Post Number: 426
Registered: 11-2001
| | Posted on Wednesday, May 11, 2005 - 11:32 pm: |
|
From the looks of the rust it may have had water inside the base. Even if it is OK inside, the device will likely not tune for a longer radiator in order to get up around 5/8 length. Those old antennas worked pretty good in their days, but they would not allow much wattage unless the coil inside is more modern and then it will be made of copper wire instead of foil.
Have to tell you, there isn't much there that is worth spending even a few dollars on. The cost of the radials will probably be more than the hole thing is worth and then you still have a low power antenna even if the matcher is OK.
Not sure from the picture, but it looks like lightning got to the GP radial bracket of the antenna.
How does the SO-239 look? |
Timebomb
Member
Username: Timebomb
Post Number: 51
Registered: 2-2005
| | Posted on Thursday, May 12, 2005 - 3:57 pm: |
|
Thanks for all the info.
I see what you guys mean about it not really being worth it to put money into it. I also did more reading in my Truth About CB Antennas book (great book, btw), and I'm learning slowly but surely!
Marconi, it looks burned on the GP radial bracket in the picture, but it's actually either black spray paint, or a weird tarnish from laying in the dirt for years! The SO-239 surprisingly looks really good. I might take it apart just for the fun of it. Thanks again for info. |
Narf_edwards
Junior Member
Username: Narf_edwards
Post Number: 21
Registered: 3-2005
| | Posted on Friday, November 04, 2005 - 9:46 am: |
|
Hey Tech,let me know if you take that loading coil at the base out.I am trying to rewind one myself for my halfwave and I need to know the number of turns/tap point info etc.I heard that the coil in the base of that unit is the same as the one in the base of the croossbow fiberglass half wave.I would GREATLY appreciate a pic or info on that loading coil.I have been posting all over the place for info but that is the exact one I want to duplicate.Let me know if you drill it out and take it apart
Thanx much
Narf |
Narf_edwards
Junior Member
Username: Narf_edwards
Post Number: 22
Registered: 3-2005
| | Posted on Wednesday, November 09, 2005 - 8:13 am: |
|
Hey Tech 808,did you manage to get a look at that matching coil in the base of that halfwave yet?Love to get a look at that sucker....
Thanx
Narf |
Tech808
Moderator
Username: Tech808
Post Number: 8307
Registered: 8-2002
| | Posted on Wednesday, November 09, 2005 - 8:44 am: |
|
Narf_edwards,
Iam sorry, but I have no idea what you are asking / talking about as I have not posted to this topic before.
Lon
Tech808
CEF808
N9OSN |
Bruce
Senior Member
Username: Bruce
Post Number: 3200
Registered: 9-2003
| | Posted on Wednesday, November 09, 2005 - 9:04 am: |
|
a classic 1/2 wave is the cushcraft ringo it uses a simple loop of wire to match. |
Narf_edwards
Junior Member
Username: Narf_edwards
Post Number: 23
Registered: 3-2005
| | Posted on Wednesday, November 09, 2005 - 1:25 pm: |
|
Sorry Tech 808...I see now my query is with Timebomb.My apologies sir
Narf.
On that note...Timebomb,have you taken that lower coil apart for a look yet?I would love the winding details on that coil so I can put mine back together...
Thanx
Narf |
