Questions tagged [trap]
The trap tag has no usage guidance.
8
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Why does my 7 MHz antenna trap have an SWR of 8?
I made a 7 MHz antenna trap. On testing it the cut-off point was 6.687 MHz which is about right but the problem I've got is the SWR was an 8 and wouldn't go down to a resonant SWR.
What have I done ...
4
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2
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Building Antenna Trap: Highest impedance/lowest capacitance/greatest # of turns?
I made my first multi band antenna this weekend for 20 and 15 meters for an EFHW wire with a 49:1 unun, to be used with 5 W rig. I used a toroid I had on hand, T80-2.
I hang this antenna in my living ...
- 301
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Antenna traps - problem with frequency change
I built a two-band antenna (20 and 40m) with traps.
I made the traps as a parallel LC circuit on the AL7 toroidal core (3 MHz - 40 MHz), I also used a 1KV ceramic capacitor. I've tuned everything up ...
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What is an expected SWR plot for a trap dipole?
I've build a trap dipole for 20/40m bands. Traps are made of a coil wound on an insulator of RG213 coax and 3 kV NP0 capacitors. The impedance measured with EU1KY antenna analyzer is following:
This ...
4
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1
answer
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Using a trap out of its resonance frequency?
I have a vertical antenna, about 7M total length, with a loading coil at 6M height. This is just because aluminium tubing is sold in 6 meter lengths. The loading coil is used to make it resonate at 7....
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Looking for a formula used by VE6YP trap calculator
I wonder whether the source code of VE6YP (Tony Field) coaxtrap design program (link 1, link 2) was ever published or described. As a Mac user I'm having little difficulties using this software and I ...
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What frequency to set trap on?
I plan to build trapped multiband dipole so I read lots of documentation I found.
There is one thing that confuses me: various authors recommend setting resonant trap frequency differently: some say ...
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Is it possible to measure antenna trap with MFJ225 without help of PC?
I have MFJ225 antenna analyzer. I measure coax trap filters by connecting this analyzer to PC and using IG_miniVNA application. That works fine.
But, sometimes I need to make such measurements in ...
- 870