Being that I'm always thinking "Outside of the Box" and ponder on things for hours, I had another wild one.. [:-)
What If..
..We used a radiator of legal length (3m) and used a slinky (metal one, of course) and used it for a loading coil? Connect it to the base of the radiator, Connect the xmtr output to the bottom and stretch that puppy out to get the desired reactance? It could be put inside of a piece of pvc to keep the weather off of it.. Comments?
Being that I'm always thinking "Outside of the Box" and ponder on things for hours, I had another wild one.. [:-)
What If..
..We used a radiator of legal length (3m) and used a slinky (metal one, of course) and used it for a loading coil? Connect it to the base of the radiator, Connect the xmtr output to the bottom and stretch that puppy out to get the desired reactance? It could be put inside of a piece of pvc to keep the weather off of it.. Comments?
My first thought is vibration changing "reactance" a little but that might work.
But... it's got potential. Is the coil considered part of the radiating element? If not, a 3' long, 3" wide capped PVC pipe with a 108" CB whip coming out the top would be fully within their radiating element limit of 3m.
I like the idea!
If you remember your Slinky commercial 🙂
Hams have used Slinkys (Slinkies?) for both elements and loading coils, so that would be fun to experiment with.
I've also considered flexible dryer duct. 4" and 6" diameter and a plastic insulation might make it easier to work with. Cut 30 or 40 turns from a big chunk, and tune it by stretching or compressing.
Also a possible 3 meter helical antenna, though a helical might not wortk at our power levels...
Experimental broadcasting for a better tomorrow!
Yeah I mentioned Helicals a while back and got pooh-pooh'd 🙂
I'm seriously thinking about trying the Slinky idea inside of the PVC.
Yeah I mentioned Helicals a while back and got pooh-pooh'd 🙂
Less pooh-pooh-ing and more encouragement and more experimentation.
Experimental broadcasting for a better tomorrow!
I had a vision of a slot cut lengthwise in the pvc pipe cover with some kind of a metal "Shelf" that the bottom of the Slinky could be connected to and a small arm sticking out of the side. Mount the xmtr to the pvc so it can slide up/down. Connect the arm to the output of the xmtr and slide it up/down to adjust the coil. After the tuning is complete, Silicone the slot shut to keep the weather out..
How far out of the box is that? (LOL)
Or, Stretch the Slinky out farther than it needs to be and snap a piece of aluminum vent pipe over the outside of the pvc cover and slide this up/down for adjustment..
Hay.. It's a thought..
Heh, I was envisioning a screw top type setup. The transmitter mounted on the bottom of the PVC and the top screws upwards to stretch the coil.
I've actually been doodling here to figure it out. I'll check out the plumbing section at the hardware store tomorrow and see if I can figure out the parts to make it telescope by turning it to adjust the coil.
The nice part about doing it this method is you can change out the radiator at any given time.
Some folks seem to like 1/2" copper tubing and others like the CB Whip. This gives users an option for their radiating element.
Hey does anyone make a 108" whip in fiberglass that's a straight (unwound) element? The last time I looked they all had fashioned a coil towards the base end of the whip.
Heh, I was envisioning a screw top type setup. The transmitter mounted on the bottom of the PVC and the top screws upwards to stretch the coil.
I've actually been doodling here to figure it out. I'll check out the plumbing section at the hardware store tomorrow and see if I can figure out the parts to make it telescope by turning it to adjust the coil.
Let there be a new antenna born from this thought.. 🙂
Some of your posts at MEN about solar and etc have inspired me in the past, so I think this makes us even! GRIN!
Some of your posts at MEN about solar and etc have inspired me in the past, so I think this makes us even! GRIN!
Another Self Sufficient Minded Part-15 Radio Head! I thought I was alone!
Kewl! Who are ya over there?
http://jcoppens.com/ant/qfh/fotos1.en.php
http://www.wb5cxc.com/designingEH.htm
http://www.wb5cxc.com/80_m.htm
Another Self Sufficient Minded Part-15 Radio Head! I thought I was alone!
Kewl! Who are ya over there?
ListerD 🙂
What would be better in your mind, variable capacitor or a good old fashioned variometer?
The PVC would only be closed hand tight and receive a silicone seal rather than glue (the radiator end might need to be glued for high wind load).
I realize this might require a bit more maintenance but then again, we're joining dislike metals so some corrosion may occur so sealing it this way would make sense for seasonal maintenance.
On that note I would also throw in a desiccant bag (What? You don't save those things?!?! :-D) in the bottom to absorb any errant moisture.
Thoughts? Surprised nobody else has piped in to this conversation.
2 3/4" in diameter
One has 87 turns, the other has 86. So it may take more than one slinky per loading coil...
What was the URL for the page that contained the turns by frequency?