I will be talking on 27.1350 ch15 am 99% of the time so that is where I need the antenna to be setup for. Thank you guys for all the great info. from what I can tell 22' 6" is where it will probally be close at.
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New Super Penetrator 500
- Thread starter basstracker1970
- Start date
BT1970, I would say your overall length idea is probably good enough for government work. go for it.
I dare not give the name of who is physically responsible for the manual, but I think they could do a much better job of giving the new owners better instructions. I use to claim the same issues about all the various older versions vs. this newer and similar SPT400'.
More information on the tip sections would seem to me to be the area that could be helpful to new owners of this antenna.
We see lots of current manufactures doing a much better job of giving their customers a kit that for all intent and purposes comes FIX as to design, and give them a scale of some sort that as the tip length and and other elements that might be used to tune. It is not real hard to do.
Before you get your's fully installed...maybe you can give us a report that suggest the frequency to length issues you got and the necessary important dimensions.
Good luck
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19 feet is meaningless for this matching network unless you need a good 32mhz 5/8.
This matching network won't match it for 1/2 wave loading on 24-25mhz. It's either a typo or as someone said, they're covering their posteriors.
that "someone " was me. that IS what I said ".. and the 19 feet figure is NOT a mistake, MFJ markets it as a 10/12 meter antenna.:bdh:
it's a CYA by MFJ. it has nothing to do with the matching network. MFJ never even addressed that or the performance on 10/12 meters.
everybody "knows" this is a CB antenna design (unless the matching rod is shorted across) but they (MFJ) just can't say that.
if someone cant figure out how long a 5/8 antenna is on 27 MHZ, then too bad.
the MFJ manual twice states the 19 foot length for the resonator as a STARTING point. after assembly and testing the manual refers to further adjusting the radiator length to alter the lowest VSWR point (not the resonance point).
when I talk with Martin this weekend, I'll pass along the "forums" concerns
as far as the "1/2 wave on 12 meters..." comment, I was "poking a stick' at the know it all.
Ok one more question. When putting this antenna together should I just clean the aluminum tubes install clamp and forget it or should I use some silicon to seal up the joints so water doesn't get into the tubes or does it matter if water gets in there. Thanks for any help.....
Might be they are going for the .64 wavelength instead of 5/8. I read about the .64 wavelength for 10 meters being a better size for that band instead of the 5/8. Maybe that's what HG is doing with yours?
5/8 wavelength is .625 wavelength. Going from that length to a .64 wavelength antenna makes an insignificant difference. We are talking a difference of .015 wavelength, which at cb frequencies is a hair over 6 inches of physical length.
Some people believe that that length makes a huge difference in their transmitted signal over a standard 5/8. In reality, local conditions will have more of an effect on your transmitted signal than that extra insignificant amount of additional wavelength...
The DB
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Did anyone read my last question? Should I use silicone to seal up the joints as I put them together or just clamp them and go on. Will water hurt them if water gets into the elements? Thank you.....
I try and protect the connectors using a product called "Stuf" from Cross Devices which is a paste like water sealer that goes directly inside of the connectors before you screw them together. It is non-conductive, and has a non-harding water sealing effect without the use of silicone and the idea is to stop water from flowing through your connectors into the feed line.
Except to the tip of my antenna tubing, I leave all the joints open so moisture can get in and out as nature provides. I also use Penetrox, a conductive grease, in the aluminum joints...which makes it easier to get apart later. Coax seal is also available if you just have to try and cover the joints too, but for me it is too messy when removing and I find it leaks sometimes. All are available from: www.AESham.com
The worse thing is sealing up the bottom areas and leaving access for water to enter from up above and then when water gets in...it has trouble getting out. Most antennas kits I've seen have and open bottom to let water out of the antenna anyway. If the radiator is sealed at the base so it can collect water...I might drill a small hole in the side to let moisture out.
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Do I need to seal up each joint with silicone or will it be ok if water gets inside the tubes. Do they need to be sealed up so water can't get in ?
IMO, it is not a good idea to try and seal up the joints of your radiator tubing, but that's just me. I don't use end caps on the horizontal beams either, and for the same reasons. And from what I hear it is not good to use silicone on coax for some reason, but it might be OK at the antenna joints.
There's a school of thought that silicon containing acetic acid will eventually corrode the connection. If your silicone has an acrid pungent smell, then it likely contains acetic acid.
I have used it years ago, but I never noticed any issues. I don't use silicone for any ham/cb related weatherproofing now, not because of the acid issue, there's just better alternatives today.
I have used it years ago, but I never noticed any issues. I don't use silicone for any ham/cb related weatherproofing now, not because of the acid issue, there's just better alternatives today.