ARRL

W1VT

Joined: Sat, Apr 4th 1998, 00:00 Roles: N/A Moderates: N/A

Latest Topics

Topic Created Posts Views Last Activity
Antenna analyzer vs feedline type Sep 21st 2012, 14:37 1 1,821 on 21/9/12
USB to Serial Port problems--Prolific Drivers Aug 3rd 2012, 18:27 1 2,047 on 3/8/12
Italian Phishing emails! Dec 13th 2011, 14:20 1 1,672 on 13/12/11
John K0GMO needs help designing SS Amp Nov 17th 2011, 15:53 1 1,545 on 17/11/11
1 Farad Capacitor to Eliminate Headlight Flicker? Oct 19th 2011, 13:14 4 2,614 on 9/11/11
History of Relay Rack Dimensions? Oct 17th 2011, 12:58 2 1,793 on 25/10/11
Miswired Selsyn Oct 13th 2011, 17:51 1 1,599 on 13/10/11
Stealth Antenna wire Sep 12th 2011, 12:51 2 2,254 on 13/9/11
Designing a ham bench Aug 29th 2011, 12:38 2 2,516 on 29/8/11
Can't find recent Hint and Kink Aug 26th 2011, 13:01 1 2,268 on 26/8/11

Latest Posts

Topic Author Posted On
Carolina Windom Antenna rs1000 19 hours, 31 minutes ago
Experimenting with different antennas is a good way to find out what works best for you.

The vertical radiator of the Carolina Windom is established by installing an RF choke at the base of the vertical radiator/coax. This does have the advantage of blocking RFI from getting to the feedpoint of the antenna via the outside of the coax shield.

An effective technique, if you have an antenna that doesn't hear well, is to listen on a battery powered radio and shut off the main breaker to the home. About 50% of the time, when the ARRL gets an interference complaint, the source of interference turns out to be in the home of the ham making the complaint.

I've found that a half wave dipole can work really well with a 120 ft feedline that allows placement well away from houses. The low SWR of a resonant dipole allows low losses despite the long feedline. The better receive performance compensates for the slightly weaker transmit performance.

Zack Lau W1VT
ARRL Senior Lab Engineer
Carolina Windom Antenna rs1000 21 hours, 5 minutes ago
It is likely that the random wire is close to local noise sources, so it doesn't hear well. Close noise sources can couple inductively into wires--but only over very short distances.

The height is a big factor on how well an antenna transmits--at low heights, vertical wires, or vertical wires top loaded by horizontal wires, can be the most effective option when a counterpoise is available. In order for the horizontal portions of the Carolina Windom to be effective, they need to be about a half wavelength above ground. For short skip 80/40 less height, perhaps 40 ft, can be effective. But, on higher bands, like 10 and 15 meters, short skip is a very rarely occurs. And, when you do get E skip, DXers are often on 6M rather than 10 meters--as 6M DX contacts are considered "more valuable."

Zack Lau W1VT
ARRL Senior Lab Engineer
cw on vhf?? KE5HDF 1 day, 8 hours ago
CW works better for double hop E-Skip on 6M than JT65--the band will often come and go before you can complete a JT65 contact. Most, if not all, of my 6M contacts with Europe have been on CW.
Both of my 2M EME QSOs have been on CW.

Zack W1VT
Signal Identification Software Capability WA1PGB 2 days, 13 hours ago
http://www.machamradio.com/blog/2014/06/fldigi-digital-modes-on-os-x
The most significant feature is full support for RSID (Reed Solomon ID) which provides a means for identifying unknown modes. When encountering an unknown mode, if the user is sending the RSID signal, the receiver can identify and tune to the correct mode either automatically or manually
Fldigi - Digital Modes on OS X
QRP Pixie Mod For Tech Band? mrmonteith 5 days, 18 hours ago
Search for "qrp crystals" on Ebay.com

Back to Top