Just the medicine for lowering impedance
Pill bottle balun
Jack-WD4E is a fellow NAQCC member and he sent me one of his QRP creations that I just had to share.
If you are staying on your meds you probably have the perfect enclosure for a QRP Balun.
If I could save RF in a bottle... |
Jack encloses his home-brew wound toroids in pill bottles.
The child and arthritis proof cap keeps the goods away from young and old alike...
Just what the doctor prescribed...
So re-purpose your medicare paid goodness and put it to work for you
Sorry all you entrepreneurs, Jack told me that he's already applied for the patent so you won't be competing with Facebook with this product idea. He owns it.
That's all for now
So lower your power and raise your expectations
72/73
For those who want to really, really save some moolah, use the toroid from one of those “power saver” lamps with the curly fluorescent tubes that are supposed to last forever but only in one’s dreams. To get into them and get the little silver dollar sized circuit board, which will probably have a blown transistor, put the bulb in a paper bag and break the glass then take out the bulb minus the broken glass. Then carefully break off any remaining glass with needle nose pliers. Use safety glasses, of course… Then cut the plastic bulb housing with a hacksaw where the two parts are joined. You may find that cutting it just enough to get a screwdriver between the two halves is enough because, usually, a good twist of a screwdriver blade will do the job.
Arnie Coro in Cuba uses the forms on 40M and I’m betting it will work at other frequencies at QRP power levels. Of course, the bifilar coil will have to be wound following one of the many Internet site directions. Usually about ten turns is enough. A 9:1 could also be made with a trifilar winding if using small enameled wire. Watch for the way the windings are connected, though.
You could even use the toroids for a decoupling 1:1 baluns and even mount the two in the same pill bottle, if one wanted, but the bottle may have to be longer to accommodate the entire works.
The SO-239 connector can be eliminated by using a PL-259 with a 6-8 inch length of coax fed trough a small hole in the bottle for connection. A dose of hotmelt glue in a few strategic places could also provide waterproofing. Ideas abound.
Before breaking a CFL bulb in a paper bag to strip a toroid, I’d recommend taking some time to think about the potential mercury contamination that might result. Just a thought…
I have opened the CFL without breaking the bulbs by cutting around the top of the base with a hacksaw and then cutting the wires connecting the bulb to the board.
The amount of mercury in a CFL is very tiny
http://earthtechling.com/2011/10/the-mercury-myth-how-much-mercury-do-cfls-actually-contain/