I agree about putting up a multiband doublet. Bracket-mount a 40' galvanized, telescoping push-up mast (order through Lowe's) with a pulley to the back of the house and haul up an 80m inverted V fed with ladder line.

Run one leg over the house to a clear place in the front yard and the other toward the back. Surely you can find some placement of the mast that will let you fan the legs out. Don't worry if they're not 180° apart - it will still radiate.

See www.qsl.net/n1lo for lightweight doublet construction ideas. I like the smaller, 300 ohm ladder line. You'll need an outboard, wide-band tuner like the LDG AT-200, a current balun, and a short coax jumper between the two. I like the switchable ratio 1:1/4:1 baluns from Elecraft or MFJ, but most of the time I end up using 4:1. You'll have a little trial and error getting just the right feedline length to tune all bands.

80m doublets are proven performers, and this setup will get you started rather simply and far below your budget. If you operate SSB, add a HearIt audio DSP.

GL,

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I also agree that the best bang for the buck is the parallel line fed 80m dipole.

Yes you need a balun in the shack with a short (<10') jumper to your tuner. One common solution is a 4:1 'remote' balun that hangs just outside the house, with a short jumper to your tuner.

I prefer the switchable impedance baluns, 1:1/4:1, which gives you the widest possible matching range. Elecraft and MFJ each offer one. The Elecraft BL2 is super easy to build.

See my antenna page at www.qsl.net/n1lo
There are some ideas for building doublets (dipoles fed with parallel line) there. I prefer the 300 ohm ladder line. It's so much smaller and easier to handle.

To cover your initial question, I also have plans there for end-fed antennas there (wire 'J poles') that work quite well and can be hung in any orientation. Never had a lick of RF feedback trouble from them and have received happy emails from other amateurs who have built them. One guy built the 20m version, then scaled plan to 15m and was quite happy with the results from both. Scale factor = (plan frequency)/(target frequency). Multiply all dimensions by SF to get new design.

This is a good forum. I learn something new almost every day. I see far less crap here these days than there was a few years ago when I first started participating.

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Ahh - no question about it, now! That tribander will completely transform your performance on both RX and TX!

You 'old' radios will be bursting with new signals.

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See my old article at www.qsl.net/n1lo for the 80-10 mobile antenna in which I describe a method for making air coils.

I found an inductance calculator on the internet that lets you plug in coil dia, wire dia, spacing, length etc. The strips I use make a coil that has 7.5 turns/in. Using 14 ga wire, the air gap is about equal to wire dia - ideal. Indenting the turns on either side of the tap point makes it easier to clip to!

See some pics at http://www.qrz.com/db/n1lo

Have fun!

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You can make an adjustable coil at the bottom of the antenna. Solder a short wire jumper with an alligator clip on the bottom turn so you can jump over and can clip onto any turn above it, to make it adjustable. This is how bugcatcher type mobile antennas and Buddipoles work to tune different bands.

It'll be much more efficient if you put the coil halfway up the mast and get rid of the helical windings (less efficient than air coil).

MFJ sells air coil stock. With a little experimentation, you can match several bands. You will need an antenna analyzer and a good ground plane/radials as best as you can fit.

'LXP Mark,

Can you post the diode spec, Mouser #, and a web link for instructions for how to DIY?

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I've had vendors at hamfests handle the MFJ guarantee immediately by an immediate swap. WOW.

If you happen to have an MFJ dealer nearby it might be worth asking.

Mark

MFJ has a 1 year "no matter what" guarantee - no worries!

Mark

I would say definitely NOT, for the average Ham. The 990 is still much sought after even as a used radio. It was my first desktop radio in 1996 and the RF speech processor, when properly set up, really rocks.

You'll get FAR more return in performance spending money to improve your antennas and feedlines.

Add an amp only after there's nothing else left to improve in the antenna system.

For ideas on how to improve your antenna system, start a new thread, tell us what you have now, and what your budget would me.

GL,

Mark

It sounds as if you might be connecting an HT to an external antenna. Assuming this, you definitely need a flexible jumper.

Consider a generous 6' piece of RG-174 miniature 50 ohm coax to allow free handling of the HT. Choose the length you need. Put a pl-259 on the 213 and on one end of the 174 (which requires a UG-174) reducer. Put the SMA on the other end of the 174 jumper. Finally, join the jumper to the 213 using a coupling.

You can buy these ht adapter cables ready made, typically around 3' long.

If you search the internet on PL-259 installation, you should get plenty of hits. There are several methods and choosing the right one can be a challenge.

Mark

see my antenna page at www.qsl.net/n1lo for a photo plan for building lightweight doublets. You can substitute rg-58 or even rg-174 for the parallel line.

I use 40' Spiderbeam telescoping masts and set the antenna around the 33' height. I have a drive-on mast base that holds the mast.

It's far simpler and faster to use the clip-on wire method I described earlier.

Mark

Here's a trick that I use for an 'instant' big signal on 80m mobile/portable.

Put a 55-60' piece of #24 wire (experiment a little to find the right length) with an alligator clip on one end and 50' or so of kite string on the other, on a kite string winder and keep it in the trunk.

Pull over anywhere, and clip the wire onto the top of your mobile HF antenna. For a bugcatcher type, put your coil on bypass. For a screwdriver, set it on 10m. The idea is to bypass all loading as you will be clipping on a full-size, 1/4 wave wire that needs no additional loading to resonate on 80m. For a hamstick type antenna, clip the wire to the base stud of the antenna to make the electrical connection, and use a loop of tape or string to hold the wire up at the top of the antenna. You may need a larger battery type clip instead of an alligator clip.

Unwind the radiator and string. You can lay it across low bushes or thread it through low tree limbs. I use a 'slinger': a 6 oz egg sinker on a 3' length or cord with a snap swivel for connecting it to lines. Toss the slinger over or through tree branches and stretch out your radiator. You get the idea: a low, horizontal, NVIS radiator.

Your vehicle has to provide the ground plane/counterpoise. Pursuant to good mobile HF efficiency, you should bond all your body panels, doors, hood, trunk & frame together. You may even benefit from another 66' wire clipped to the vehicle body and stretched out in the opposite direction as the radiator. I haven't done enough testing to confirm how beneficial this actually is.

I have used this same wire to operate on 160m portable, with my mobile HF antenna loading set for 80m.

See my current antenna at http://www.qrz.com/db/n1lo  I have connection points above and below the coil for clipping on low-band extention wires.

GL,

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1st problem: both antennas need to have the same polarization for local groundwave comms. The usual propagation for long distance radio contacts is via skywave.

Your mobile hamstick is vertically polarized. For the best GROUNDwave distance, use a vertical antenna as high as possible at home. Reorient the buddipole at home as a vertical and try again.

Next, you find out that groundwave comms don't really carry that far, and that incoming skywave signals will clobber the ground wave signals.

Good Luck,

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As already pointed out, the wire gage is driven by mechanical strength considerations. I have run legal limit into a 22 ga wire antenna.

Your feedline rating is the primary concern.

Regards,

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Hi Tom,

I second the idea to check any pl-259's in your system. If you have a poor solder joint, which is very common, any slight movement of a coax jumper can make it jump state. Having an analyzer makes it easy to test your jumpers.

Pick up an inexpensive 50 ohm 'network terminator' from Rat Shack to keep with your analyzer. This miniature dummy load usually has a bnc connector. With the right adapter, this is a real compact way to test your jumpers individually, with the terminator on one end and the analyzer on the other. Be sure to give each connector the 'wiggle test' to detect bad solder joints: push, pull, and twist the coax adjacent to each connector while watching for any jump in the SWR reading on your analyzer.

GL,

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