Re: Antenna for AM MAX II DSP

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Robert Dillon
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Re: Antenna for AM MAX II DSP

Post by Robert Dillon »

Can anyone share what type of Antenna/Antenna design they are using with this unit? It seems all I can radiate with this thing is a 8' wire at full power and only get out 500'. Please help !
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pcs
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Post by pcs »

AM antennas are crucial in getting a good range.

Unsuitable antenna can even cause bad modulation due
to attenuation of the segment of the signal (uneven radiation).

Some links to AM antenna designs are posted on our website just
under the product.

Otherwise it would be a good idea to search/look at the 160m
ham antennas and make them just a little longer.
Best regards,
Marko - PCS Electronics
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erobertg
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Low Cost AM Antenna…

Post by erobertg »

:D The AM Max II DSP transmitter has a low impedance BNC output. Simply placing a short piece of wire to the center pin wont give you squat for range, at best a couple hundred feet with a good radio. You wont even drive the transmitter as it needs the equivalent of a 50 ohm load. An antenna tuner is needed and I’ll get to that later.

First off, the 1610-1700 kHz portion of AM band has been opened up about ten years ago and there are some frequencies free and clear. Additionally, the new high end of the AM band is adjacent to the 160 meter amateur band and there is a lot of low cost ham equipment available to help you.

The first thing you’ll need is a 100 watt SWR/Watt meter and that can be had for $17.95.

http://www.oselectronics.com/ose_p115.htm

While your at it, get a couple 5 watt 50 ohm dummy loads ($1.50) from the same source. These 5 watt dummy loads will work just fine for a minute or so and will allow you to check the wattage output of your transmitter. Once that has been established, you new can check into that antenna tuner.

I recommend the following low cost tuner…

http://www.mfjenterprises.com/products. ... =MFJ-16010

For $49.95 you can drive anything from a high impedance 100’ random wire, your bedsprings to resonance or a metal slinky hanging from your ceiling. The unit is a simple L-Network that is rated up to 200 watts. If you should find that you need to tune even lower frequencies simple solder 100 pf capacitor across the tuning capacitor of the antenna tuner. There is even downloadable manual to check the schematic and read the instructions. With your SWR meter in line simple tune the unit to drive your transmitter while achieving the lowest SWR to 1:1 if possible. You’ll now get out a few miles.

And that’s it, some praise and good ideas from some hams.

http://www.eham.net/reviews/detail/2379

An Antenna for under $100 including wire...Have fun!
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