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Re: 2010-06-26 thru 27: SummerFest Field Day Planning
Posted: Tue Jun 08, 2010 11:28 am
by xtatik
sdnative wrote:I was listening to the guys on the BB repeater last weekend. One of them built a pneumatic tennis ball launcher to get the antenna pull line really high up in the trees. Using an "enhanced" tennis ball, he was able to get over 10 seconds of hang time. That's about 300'+ of elevation
Steeevo, is working on one............Steve, how's it coming together?
Re: 2010-06-26 thru 27: SummerFest Field Day Planning
Posted: Wed Jun 16, 2010 1:40 pm
by DaveK
Randy;
The 80 m bandpass filter arrived today. I think that this completes the compliment of filters that we needed. Couple of questions:
1. It comes with a grounding screw and the instructions note that the units can be grounded so as to, "offer better performance". They also note that "in most cases, the stations earth ground will be sufficient." For the vehicle mounted Scorpion, will the existing vehicle ground be sufficient and if not what would you suggest as a proper grounding source?
2. Apparently the filter can be tuned to a different center frequency. Do we need to address this?
3. We will need several short lengths of co-ax to make these connections. If someone has several or if we can get an inventory from each operator, we can make sure to have the necessary equipment.
I am bringing an MFJ 259 antenna analyzer (HF & VHF). Does anyone have a UHF analyzer.
Re: 2010-06-26 thru 27: SummerFest Field Day Planning
Posted: Wed Jun 16, 2010 5:25 pm
by xtatik
DaveK wrote:Randy;
The 80 m bandpass filter arrived today. I think that this completes the compliment of filters that we needed. Couple of questions:
1. It comes with a grounding screw and the instructions note that the units can be grounded so as to, "offer better performance". They also note that "in most cases, the stations earth ground will be sufficient." For the vehicle mounted Scorpion, will the existing vehicle ground be sufficient and if not what would you suggest as a proper grounding source?
2. Apparently the filter can be tuned to a different center frequency. Do we need to address this?
3. We will need several short lengths of co-ax to make these connections. If someone has several or if we can get an inventory from each operator, we can make sure to have the necessary equipment.
I am bringing an MFJ 259 antenna analyzer (HF & VHF). Does anyone have a UHF analyzer.
I've made a number of station ground rods (6, I think) and I think steve was working on this as well. I also mentioned on our worksheets to bring a short 6'-10' coax section for the inline placement of the filters. We can ground either way at the filter or below the stations. The outer of the 239 on the back of your radio is common with the radio chassis as far as ground is concerned. It would be the same at the filter. Grounding at the filter may be more distant but probably wouldn't matter. I have never seen them used with the ground option at the filter.
I haven't looked at ICE's website to see where they tune the filters. I'm pretty certain they'd default to the SSB end of each spectrum. Either that, or they push a compromise in-between. I'll check it out.
I'll be bringing a 259b with me....no UHF. Will someone be doing some "refined UHF" work? Otherwise, I don't think we'll need it.
EDIT: Dave, I just jumped over to their site and checked the tunings. They are fairly broadband within a given band. The 80m is set to pass from 3500 to 4000. Naturally, they're tuned to center at apporx. 3750. Each appears to be well centered in the Amateur bands....fine biz.