All it does is power the bulb but positive is center pin.

No idea what the size is but any electronics component shop should have one that'll fit.

Where is the one for the victims of the bombings in Iraq that took place on Monday and killed 55 and injured over 300?

Your tuner is in no way wide ranged enough to tune it for 20m.

You might want to try 15m as it is a third harmonic of 40m. That should be well within the range of the internal ATU and give surprisingly good performance.

These masts are very popular in the UK, especially the pump up versions. I've just bought a pneumatic 10.7m Hilomast simply so I can raise and lower it as required.

THEY DO NEED GUYING if you're going to leave it up or use when windy.

Alter your existing matching coil. It should provide an acceptable <1.5:1 SWR on all the bands. Don't get hung up on trying to get a 1:1 SWR operating mobile.

If you can't get an acceptable SWR below 1.5:1 on all bands, look at your mounting and bonding.

Here is how it all works on HF.

http://www.tpub.com/neets/book10/NTX2-19.GIF

Ground wave is how far the signal travels along the ground. You then have the Sky Wave Coverage which is where the signals bounced off the ionosphere land and inbetween the ground wave coverage and the sky wave coverage is the skip zone where you will not be able to hear or reach any stations.

They may be able to have the 10m net because they're all within the ground wave region and you aren't. Ground wave on 10m is only a few dozen miles - 50 at the best.

Lower HF bands, horiztontally polarised antennas and keep the antennas low - NVIS. 80m band will do that just fine during the night and 40m band during the day. You won't get a reliable mobile solution for vehicles though.

Only an option if you're mounting it up in the air. If you're ground mounting it is a waste of time and money.

Easiest way to do it is to get a square or round slab of metal and have the appropriate number of 3/8" tapped holes put in to mount the hamsticks. Tune each for lowest SWR on the relevant band and pop them in. Hook the braid of the co-ax up to the block and mount the whole lot directly below the 4BTV as close as possible.

The default setting of 300Hz low and 2700Hz high is just fine.

"SWR makes you stupid" is a term used and an article has been written with the same title.

My inverted L has a SWR of >85:1 on some bands. I use a SGC230 antenna coupler at the feedpoint to tune it. It has absolutely zero problems getting out and I've worked the world with it and 100W as well as contesting with it winning a 1st in World in class in the 2011 CQ-WPX-RTTY contest.

Now that SWR tuned at the shack end of a length of co-ax is a bad thing due to feeder losses but that is less of an issue on ladderline.

The biggest difference, in addition to having less menu diving, is in strong signal handling. It'll cope better with nearby strong signals.

Yes you need radials. No you do not EVER use a tuner with a screwdriver antenna - you'll kill the coil. You adjust the antenna to get the lowest SWR, not use a tuner.

I made my own cables up. They're pin for pin straight through so as long as it fits at either end you'll be OK. The radio end of the head separation cable is an 8 pin RJ45 connector.

Over a range of hills.

http://goo.gl/maps/uKb3P

I'm in Driffield, the repeater is west just below and to the left of where it says Batley south of Leeds. As you can see there's a range of hills in the way to the west of Driffield.

The 5/8 may work better over flatter ground but the difference is a couple of dB, hardly noticeable. Although you may open the repeater and be able to hear that someone is there, the audio will be so intelligible to make the fact you can open the repeater quite pointless.

The difference will be around 6dB or 1 S point in the quadrants where no radials are. It should still hear plenty in that direction, just not as good as it could've done i.e a signal which would've been S7 had there been radials will be around S5-6.