So, there a few here in Alberta thinking of trying 160 and 80. We are all pretty well SSB. What frequencies (for antenna building purposes) for these and sort of timeframe??
Malen
VE6VID
For 160m, operation is usually down towards the lower part of the band. My suggestion would be to build a 250 ft doublet and do the tuning at the rig. Far easier that trying to resonate a low and long antenna in the field. You will need a faily tall mast to keep the wire off the ground. I would suggest 10m. That’s what I’m planning on anyway.
80m is much easier of course.
To clarify what Richard wrote: in this country we have a severe power limitation over most of the band but can use high power at the low end, so we usually operate SSB on about 1.846 MHz, though this is now getting pushed at by digital operators. Other countries may not have the same problem. The band is restricted in range during the day and goes very long after dark, a good compromise is to operate when the sun is low, near sunset and sunrise.
I was a bit surprised to find that I could chase effectively with a G5RV set up as a doublet, but for activation purposes I am going to try a W3EDP antenna with a loaded counterpoise.
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I was thinking about making loading coils to use in conjunction with my Bandhopper 4 to allow activating on 160m. But maybe not the best approach, and i haven’t got a clue how to make them anyway.
Tom, the radios we use want to see the impedance of the connected antenna as 50+0j ohms. i.e. the impedance is all resistive and not reactive.
If an aerial is physically short (i.e. 80m dipole on 160) then the impedance will have a capacitve reactance and it wont look like 50Ohms. i.e expressed as X-Yj where X is the resistance and Y (-ve) is capacitive reactance.
+j = inductance and -j = capacitance
You need to add +ve reactance (an inductor) +Yj to that so the +Y and -Y add up to 0 and that removes the reactance.
People make their short dipole work by adding in inductance to the elements. You can do it by adding an inductor at each end or at the link point for a multi-band link dipole.
Setup the antenna (80m dipole on 160m) and measure the feed point impedance to see how much -j you have. Use Google to find out how to wind a coil that will have +j reactance at the frequency you want. Wind coil, insert it in element. Measure impedance and faff about with turns etc. until feed is 50+0j.
Faffing about is made easier if you have some kind of slug you move in and out of the coil you have wound to adjust how much inductance you have. Also there will be interwinding capacitance in your coil which will make the amount of +/-j you end up with not quite what the calculations say.
Like washing hair (wet, lather, rinse, repeat) there is plenty of measure, calculate, fabricate, measure and repeat involved and this is known as engineering fun.
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A calculator can help reduce the amount of faffing…
e.g.
https://m0ukd.com/calculators/loaded-quarter-wave-antenna-inductance-calculator/
(other on-line calculators are available!)
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IIRC, in his GX0OOO activations on Top Band, John adjusts the slug in his loading coils on site before every activation. I assume that this is necessary because of the range of ground conditions affecting a low dipole. I would prefer the convenience of making all my adjustments at the transmitting position using a tuner, accepting the losses that a tuner may impose. The learning curve is going to be quite interesting!
Ooooo, nice site. I need to faff about here first instead 
Yes, and I think John has to make an adjustment when moving between the SSB freq, and the CW freq.
The one and only time I activated on 160m (during the total eclipse a few years ago) I used a doublet cut somewhere near a half wavelength, and matched with an Elecraft T1 tuner.
The “feeder” was formed from the same wire as the doublet, I zip tied the two lengths of wire at the feed point, then taped them together every metre or so until I had a long enough lead. From memory, I bought a 100m spool of hookup wire, and folded it in half. No joints anywhere.
Supported at the centre on a 8m pole.
This made a few contacts for me running 5w from the FT 817, and is what I intend to use for this challenge…
Looking forward to it!
Edit: The point being that the antenna was very quick and easy to make, if you just want to try out the band without a lot of expense or faffing… 
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