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Spring / Summer 2013 Update

Haven't really updated the site in a while, been busy and have not had much of a chance to do anything more than some 2M/70cm FM while driving to work. It was a pretty cold and snowy Winter, however mostly uneventful. The repeater project is going ok. Still testing some stuff out, and quickly realizing that height is king. Where the antenna sits now appears to be in a bit of a valley. Unfortunately it is not on a tower, or other high perch. Coverage is a meager 2 miles, maybe. BUT with a clear shot through the valley, I can hear it about 20 miles away on my way to work as I crest a hill.

It's already February!, NAQP, House Hunting, and more...

It's already February!, NAQP, House Hunting, and more... Wow, where does time go, well here is just a little summary of some of the ham projects I am working on....

Repeater Testing

Well, results are less then stellar at this point. It has about a 2 mile radius at best. This is with only 6 Watts of output. I am fairly sure it hears much better then it transmits, One of two things will have to happen. 1) get an amp! At 6W I am already over the 100% duty cycle rating of the TKR-820 (5W) I can go to 20W if I run a 50% duty cycle, but if anyone gets to rag chewing, it is going to stress it beyond what I am comfortable with. A nice 50 or 100 watt amp should be fine, probably go 50W to start, and move up from there.  2) A better antenna would help as well.

2012 New York QSO Party

So , New York had their QSO Party this past weekend, and while I did not get a lot of time to be on air, I did manage 40 or so SSB QSOs in the two hours or so i had to operate. I am still having mixed feelings about the new OCF Dipole I put up earlier in the spring. While the noise is better (further away from the buildings) I am losing more in line loss, just how much remains to be seen, or calculated. I tried e-mailing the tech dept of the cable manufacturer, but have not heard a reply. I am going to give them a call in a few days if I don't hear back soon.

Search for a better VHF/UHF Dual band Mobile Antenna

 

Since transferring within my company to a different office theTM-D710 in my car is getting much more use during my daily commute to and from work. For the most part I can get into the local repeater, but at the far end of my communte I am not holding the repeater as well as I should. I guess it is time to look for ways to improve, one way is a better antenna.

Taking down the 80M/40M dipole.

Well, I guess it is a sad day. I had to take down my first antenna. The 80M/40M dipole, it has been up for about 18 months and gone through a few storms, one that even stretched and snapped it, but I put it back up. It wasn't a storm that took it down, but tree maintenance that made me decide to pull it down. The property maintenance company at the condo where I live was doing some tree trimming to attempt to reduce the amount of moss growing on the building.

Thoughts on the 80M OCF Dipole

So, I have had the off center fed dipole up about a week now, and one thing it definitely is, is quieter. Where the 40M/80M dipole had a lot static, due in part to being very close to the condo building I live in, the 80M OCF Dipole has much less man made noise on it. Most bands above 7 MHz are 0-1 S unit of noise, and below that there is about a 4-6 S unit reduction in noise. There is a whole lot more going on out there. I am even able to here some activity on 160M, but I think it is much too short for transmitting on 160m.

80M OCF Dipole

So... Instead of putting up a 80M Dipole I decided to put up a Off center feed (OCF) Dipole. It is a little different then a regular dipole in that it is not feed at the center, as the name implies it is feed some distance from the center. I decided to go with the 80/20 split. With this split I should be resonant in the 80, 40, 20, 10 and ?? meter bands. Not bad for about 137' feet of wire and a balun. I'll explain the construction and theory behind the OCF later, but now let me tell you about my issues getting the antenna in the air.

Ideas for a Shortened 160m Dipole

 In the few days I had a MFJ-962D manual tuner (had to go back as defective) I found that reception on the 160m Band was improved some what. This was using my 80m/40m dipole as the antenna. I don't recall if I tried loading the antenna through the tuner, but reception was better. This is somewhat promising, perhaps I can get out on 160m now. Either that or I find a small 160m antenna.

RF Squirrels

What are RF Squirrels? RF Squirrels are tiny little animals that love to eat RF carrying conductors. Conductors such as coax, twin lead, etc.... This weekend I was working on my 40/80 Meter dipole. I wanted to get it up another 2 meters or so, as the 'winter storm' of October 2011 did some tree trimming for me and I can reach up another 6-8 feet with a throw line. It's only up about 25 feet, a little low! When I pulled the center insulator down with the coax feed line, the coax was chewed and/or pecked in several locations. [insert pictures] I even saw some center conductor damage.

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