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Latest Topics

Topic Created Posts Views Last Activity
Antenna analyzer vs feedline type Sep 21st 2012, 14:37 1 1,819 on 21/9/12
USB to Serial Port problems--Prolific Drivers Aug 3rd 2012, 18:27 1 2,045 on 3/8/12
Italian Phishing emails! Dec 13th 2011, 14:20 1 1,669 on 13/12/11
John K0GMO needs help designing SS Amp Nov 17th 2011, 15:53 1 1,544 on 17/11/11
1 Farad Capacitor to Eliminate Headlight Flicker? Oct 19th 2011, 13:14 4 2,613 on 9/11/11
History of Relay Rack Dimensions? Oct 17th 2011, 12:58 2 1,790 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 2,252 on 13/9/11
Designing a ham bench Aug 29th 2011, 12:38 2 2,514 on 29/8/11
Can't find recent Hint and Kink Aug 26th 2011, 13:01 1 2,266 on 26/8/11

Latest Posts

Topic Author Posted On
Signal Identification Software Capability WA1PGB 21 hours, 13 minutes ago
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 4 days, 1 hour ago
Search for "qrp crystals" on
question about wi-fi routers WD6EJN 5 days, 2 hours ago
Wireless microphones are commonly used in churches--here is a forum with a lot of discussion that you may find helpful

Zack W1VT
Common mode Choke for Balanced Parallel Feed Line AG6CX 5 days, 20 hours ago
One way to measure transmission line losses is to build two identical systems and run them back to back, and then measure the insertion loss of the back to back system.

Another approach, is to build the antenna system and measure the balun heating, perhaps with non-contact IR thermometer. There are even hams who have access to thermal imaging cameras, as these have become more affordable.

Zack Lau
ARRL Senior Lab Engineer
Common mode Choke for Balanced Parallel Feed Line AG6CX 5 days, 21 hours ago

Perhaps you could work with the manufacturer to obtain a 2 port model of the balun and model it with intended open wire systems to estimate the efficiency. L.B. Cebik used to do similar investigations for other hams, as a retired math professor, but he is now a silent key. His work is now behind a paywall, as he realized that a volunteer wouldn't maintain the site without some financial incentive.

Zack Lau W1VT
ARRL Senior Lab Engineer

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