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2 answers

Coaxial Folded Dipole Antenna Matching Impedance

In http://www.nsw.wicen.org.au/technical/projects/coaxial-folded-dipole-antenna, the guy is using a 50 ohm coax cable to build a folded dipole antenna and claims that this will enable use at 50 ohm (I assume the required matching impedance). Now,…
user4575
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Command-line satellite tracking software

Is there any software similar to Gpredict but which can be used without a GUI and can control rotor Az/EL and radio doppler shift? I'm using Linux in particular, especially Ubuntu 14.04. Currently, I can control rotors and radio via Gpredict's…
user80551
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What does multi-path sound like on FM?

I know I have probably experienced multi-path propagation on FM modes when I was working a repeater in the grand canyon and in the mountains. How can I identify when I am getting multi-path, and what does it sound like while using frequency…
Skyler 440
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Are there any satellites with 435 MHz uplink?

I have a transceiver working in the 435 MHz ham band. I want to test my uplink capability by communicating with satellites operating in this band. Are there any digital satellites which I can use for this purpose?
Ashish kulkarni
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2 answers

How should I mount a mobile antenna on a vehicle with a non-conductive body?

I would like to mount a self tuning antenna, ATAS-120, matched with the FT-857D transceiver. I would like to make this pair function on an ARGO 8x8 amphibious vehicle with a polyethylene body. There is a metal frame the engine and drive-train is…
scott
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4
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2 answers

Where does one find high-voltage variable capacitors and inductors for RF?

I'm looking to start building various antenna tuning circuits, but I'm limited by my parts inventory. I have pots and mag wire for winding inductors and a nice spectrum of fixed-value capacitors, but I have no high-voltage parts, nor variable…
wolak
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4
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2 answers

Can IMAP email be used for packet radio?

I just barely learned that IMAP is a protocol that allows you to read and respond to emails without using the internet. Would it be possible to use this application for packet radio and if so, how? I am using the Ubuntu 14.10 operating system.
BJsgoodlife
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1 answer

Color of radio noise?

Is typical background RF plus radio receiver electronics noise (wide-band audio) closer to white noise or pink (1/f) noise? Does it depend on the demodulation scheme (AM/FS/SSB/etc.), if any, currently configured or the band being tuned?
hotpaw2
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Conversion from Baud to Bits per Second and then to Bytes per Second

How would I go about converting from Baud to Bits per Second (bps) and then from Bits per Second to Bytes per Second (Bps)?
W8AWT
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What is the difference between Yaesu noise blanker (analog IF) and Icom noise blanker (perhaps digital)

What is the difference between the Yaesu (say FT DX 5000) and Icom (say IC 7700) noise blankers? I understood that the Yaesu NB is an analogue one while Icom uses a digital solution.
Nicola
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4
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Listening below the carrier frequency gives a weaker signal than above the carrier frequency - why?

I have a 20m CW transceiver with an option for a wide or a narrow filter. When the narrow filter is selected, a crystal ladder filter is used in the intermediate frequency filter, between two mixers. When the wide filter is selected, this crystal…
user885
4
votes
2 answers

AX.25 to Kenwood $PKWDWPL sentence

In my vehicle, I have a Byonics TinyTrac4 paired with an AvMap G6. I also have a Kenwood TM-D710 that I'm currently using for voice. I live in a region of the US where both 2m APRS and 70cm High Speed APRS are in common use, and am interested in…
KD7KUJ
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4
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Resistive impedance with frequency

Full disclosure, I'm a little dyslexic. Concepts that are easy to most people usually seem ambiguous to me. I also have a had time expressing myself through writ so please forgive me if this seems like an odd question. I've been reading my ARRL…
Turingrad
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1 answer

Using a flip-phones GPS NMEA data for the GPS in an APRS station

I have heard that it is possible to connect certain flip-phones to external devices via their Micro USB port and, through the USB port, send the NMEA location Data from their internal GPS to an external device. I am wondering if it would be possible…
W8AWT
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4
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How can I establish a wireless link between my PC and TenTec 506 / chipKIT UNO32 using USB port?

I have a TenTec 506 HF transceiver that uses a Digilent chipKIT UNO32 microcontroller. My PC running Teraterm (serial connection) or the MPIDE monitor is connected to the microcontroller's mini B USB port to read frequency, RIT, voltage, etc. I…
Terrance Leach
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