Showing posts with label repeaters. Show all posts
Showing posts with label repeaters. Show all posts

Saturday, June 27, 2015

Plans for an Arrow Antenna

Over on Bushcraft USA, another member linked to this PDF version of an article from the April 1992 issue of 73 Amateur Radio Today by KA0VFF and N0IMW on how to build a 2M Yagi antenna using aluminum tubing and aluminum arrow shafts for the elements. In the thread discussing it, the poster mentioned being able to check into a repeater on Greens Peak in AZ, from Flagstaff, a distance of about 150 miles using 50 watts. Pretty damn good, IMO. (The thread is here, but I think you need to be registered with BCUSA to view it.)

As a 4-element design, it should have a little more gain than my 3-element Yagi from Arrow Antennas. This will manifest itself only under extreme conditions, however.

With suitable weather sealing, it looks like this design would be a good choice for a permanent mount.

Finally, N5DUX's site has a good collection of ham-related PDFs. It's worth checking out.

Tuesday, November 25, 2014

Building a Bucket Ham Repeater

As found at ModernSurvivalOnline.com:

The “Bucket Repeater” is a battery powered cross-band VHF/UHF repeater in a weather proof enclosure that can operate unattended for a week or more, and be remotely activated or deactivated from miles away as needed.

LINK.

I will say that he's probably get better performance by substituting a 1/4 ground plane or copper J-pole for the magnet mount antenna. The latter has the advantage of easy mounting, not to mention the fact that you can buy a decent one from Amazon for around $20, already assembled.

A cross-band repeater like this is valuable for groups who want to communicate over distances or terrain which would normally block an FM signal. For example, you might have two people who need to communicate via UHF or VHF, but one's home is located in a hollow, the sides of which block the radio signal. A cross-band repeater like the one described in the linked article could be placed up in a tree on an intervening hill, allowing two-way communication.

An alternative if you do not have a radio capable of cross band repeat is a simplex repeater like the MFJ-662 or Argent Data Systems ADS-SR1, which use the store-and-forward technique. A simplex repeater might be easier to setup, but cross band repeaters provide better realtime commo.




Thursday, September 11, 2014

The Penn N3KZ Linked Repeater System

The University of Pennsylvania runs the N3KZ UHF linked repeater system (Internet-linked, AFAIK). It covers SE PA, some of NJ, and NE MD. I was scanning through the memories on my FT-7800R and caught a call on the one in Eagles Peak, Lebanon County, PA. I wound up having a nice chat with a new ham who was using the N3KZ repeater in Havre de Grace, MD. I'm about 50 miles from the Eagles Peak repeater. My rig was set to 10W connected to a Comet GP-3 on my roof, while he was on a Yaesu FT-60R HT with a roll-up J-pole.

Internet-linked repeaters are a nifty blend of old and new tech. Obviously, such a system is more vulnerable to going down in a major SHTF scenario but it's a nice option when it is up, especially for those hams who can only operate on VHF or UHF.

Here’s detailed info about the N3KZ system from Repeaterbook.com: http://www.repeaterbook.com/repeaters/details.php?state_id=42&ID=168#sthash.FbOLU8Gt.dpbs