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Re: [VHFcontesting] Running a big enough station for portable operations

To: vhfcontesting@contesting.com
Subject: Re: [VHFcontesting] Running a big enough station for portable operations....
From: David Pruett <k8cc@comcast.net>
Date: Sat, 20 Jun 2015 00:35:48 -0400
List-post: <vhfcontesting@contesting.com">mailto:vhfcontesting@contesting.com>
I have to wholeheartedly agree with what Marshall wrote.

When I first got on 6M during the summer of 1989, I yanked one of my 10M yagis off the tower and stuck a 6M PV-4 (4L on a 12' boom) in its place and operated thru the summer with a Yaesu FT-726R at 10W. Now this was not at all a bad setup (the yagi was at 90' AGL) but it was very frustrating. I could hear more than I could work, the problem being that I often had to wait in line to get thru and the band would often fold before the pile thinned out enough for me to be heard. At the end of the summer, the 6M beam came down and the 10M beam was reinstalled for the fall HF contest season.

The following summer, I picked up a used HyGain 66BS yagi (6L on a 24' boom) and threw together a little 100W amplifier using a spare set of 6JB6 sweep tubes (e.g. Drake Line finals) and the AC-4 power supply from my C-Line. Wow! What a difference! 10 dB more power and probably 3 dB more gain in the yagi meant that I waited in line less often and more often got the QSO before the band dropped out.

The third summer, the 6L HyGain went back onto the tower, and I picked up a used SB-220 which I converted to 50 MHz. With the same old FT-726R driving the 6JB6 amp to 100W, the converted SB-220 put out 1000W. Now, not only did I get thru the pileups early, but I could also call CQ and attract DX. Life was good...

I tell this story to show that incremental improvements truly *DO* make a significant difference. Every dB counts, particularly when dealing with a band like 6M where the propagation can drop out without warning and leave you without making the QSO. As I found in 1989, you *CAN* work good stuff with QRP on 6M if you're willing to wait for the right conditions and competition. But, how long are *YOU* willing to wait?

73, Dave/K8CC


On 6/19/2015 11:25 PM, Marshall-K5QE wrote:
Hello everyone interested in 6M for portable operation.....

I have done several different 6M portable operations to rare grids. The difference between a station running a 3el beam and 100W and a station running 5 or 7 el and 1KW or 1500W is just HUGE. We ran a 7el M2 and either 1KW or 1500W(when we were running EME--yes we ran EME off a boat!!) and we worked 1500+ stations in 3 1/2 days. You just don't get that with a 3el and 100W, I don't care how nice the propagation is.

The reverse is also true. Fixed stations running a 3el and 100W are about 15db down from a 7el and 1500W. 15db down is a LOT!! There are many MS and tropo contacts that are lost because stations are not running sufficient ERP(power + antenna)....never mind EME contacts. I know that you can make contacts with 100W and a 3el, because there are hundreds of them made every season. But you will make a lot MORE with more goo.

One of the things that I "preach" to operators contemplating portable type operations is that you need to be sure that you have plenty of station for what you are trying to do. Some guys catch on and some don't......

There are numerous solid state 6M amps running around nowadays that will give you 1KW+ output...get one of those.....

73 Marshall K5QE

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