• PhilK

    by Published on 10-26-2017 06:27 PM
    1. Categories:
    2. Cell Phones
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    I have been given or purchased
    a number of various USB power banks. These power banks are designed to replace the AC outlet with a USB power supply so that when you're in the field and do not have access to an AC outlet, you can still charge or power your USB powered device The ubiquitous cell phone is our main USB powered/charged device, but there are other things, such as Bluetooth speakers, which also require a 5 Volt power source to recharge.

    But, what does it mean to have a 10 amp-hour (Ah) USB power bank?

    When testing batteries for amp-hour ratings, the battery is expected to be able to run down to ~ 80% of its nominal voltage and still be able to be properly recharged. So, 80% of a 12V is ~ 10.5 Volts. Actually, 80% of 12V is about 9.6V, but since a 12V battery is really a 12.6V battery and the cut off is usually considered to be around 10.5V, this comes out to ~ 83%.

    The Ah rating is normally found by running the battery ...
    by Published on 08-11-2017 10:18 AM
    1. Categories:
    2. TV Antennas
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    If you browse through this site, you'll find a number of articles that tell you that amplifiers cannot amplify that which is not there but that they can help you get your signal to your TV. I have been asked on occasion why a certain TV channel was lost after adding an amplifier when the station was intermittent before. Shouldn't the amplifier have amplified the poor signal into a good usable signal?

    When I went through school, I didn't love to push numbers at first, but somewhere around learning algebra, I started seeing connections and really ...
    by Published on 06-20-2017 10:01 AM
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    2. TV Antennas
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    This is the last article in the series of bow tie (BT) antenna tests. In this test, the angle used, or put another way, the separation distance between the two ends of the BT "V," was changed to see what effect this had on the signal levels of the various TV channels.

    The approximate separation distances and approximate angles used were:





    Each pair of elements was attached to the BT antenna mount and all tests were run for that antenna. First, a set of readings for the standard angle of approximately ...
    by Published on 06-08-2017 11:24 AM
    1. Categories:
    2. TV Antennas
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    The Stealth Hawk Antenna Gedanken (Thought) Evaluation

    The Stealth Hawk Antenna is made from a single 60” (5’) long piece of wire. The design I used as my template was:


    [VHF-UHF07-51]

    The top section was 30" long. Essentially, this is simply a 30" full-wave loop, so the full wavelength is 30", which is for about 394 MHz.

    This is between channels 13 & 14, which are frequencies of 210 - 216 MHz and 14, 470 - 476 MHz respectively. This is a bit longer than that needed for the UHF frequencies ...
    by Published on 05-09-2017 02:10 PM
    1. Categories:
    2. Misc. Gadgets
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    Recently I learned that the FCC is proposing to change a few things in the personal radio service.

    Some History:
    At one time, the only free personal radio service was the CB (Citizen Band) radio service. It is located in the 27 MHz (11 m) area and is limited to 4-Watts of AM (amplitude modulation) or 12-Watts (PEP) for Single Side Band (SSB) output, The basic 27 MHz CB we know today was created in 1958, ...
    by Published on 03-01-2017 03:55 PM
    1. Categories:
    2. TV Antennas
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    With the change to DTV
    we ended up with "Virtual" Channels what are these?

    The "real" channels are the channels the TV stations are using to transmit on. Back before HDTV, the channel number told us what frequencies the TV station was using. We became so used to the channel number being the be-all and end-all for a TV station that the FCC or the broadcasters (TV stations) thought we'd get really confused ...
    by Published on 02-28-2017 10:51 AM
    1. Categories:
    2. TV Antennas
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    Let’s go over a few things about dipole antennas that I have picked up while being an amateur radio operator. I will start with what is known and go from there. I will then apply this to over-the-air TV and simple Bow Tie TV antennas.

    A word of warning: One of the things I learned when I was a boy was that if you have an idea, give it a try, and see what happens. In school, I learned that sometimes what you don't know can kill you (think about Madam Curie and radiation). So, please think about what you're going to try and ...
    by Published on 02-21-2017 08:05 PM
    1. Categories:
    2. TV Antennas
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    This antenna was an extension of an idea I had back in 2002, and had an article published about the precursor antenna in Popular Communications, in January 2003: "Phil's Easy Way To Improve Your UHF TV Reception."

    The next article published shows this antenna completely as I still use it today. This article was published ...
    by Published on 02-15-2017 02:39 PM
    1. Categories:
    2. TV Antennas
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    I was given an antenna by a family member who didn't want it any longer: It is the RCA, ANT 140. The label said: Thomson Consumer Electronics, Deptford NJ 08096-2088. I don't know who the real manufacturer was, but it was made in China.

    Looking on the Internet I found:
    THOMSON Consumer Electronics Inc./RCA
    10330 N Meridian St.
    Indianapolis, IN 46290-1024
    P: 317-587-3000
    F: 317-587-6765

    I don't know if they are one and the same company who designed this small amplified indoor TV-FM antenna. My guess is that it was ...
    by Published on 01-27-2017 12:47 PM
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    The location of the antenna is one of the most important elements of signal reception for radio waves. DTV is using the same frequencies for the stations as before except that channels below 7 are no longer in use. Those stations had to move to higher frequencies. An example of this is Washington’s WRC, Channel 4, which ...
    by Published on 11-16-2016 11:58 AM
    1. Categories:
    2. TV Antennas
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    Description:
    The device is sold for ~ $32 at Solid Signal without any coax.
    King Controls SureLock SL1000 Digital TV Signal Finder (SL-1000) from Solid Signal

    The claims are:
    LED lights indicate where DTV signal is strongest
    Variable sensitivity adjustment
    Foolproof antenna pointing in both strong and weak signal areas
    Also compatible with HD for DTV
    Pinpoint the location of local DTV towers
    Point the antenna before scanning for channels
    Saves time and frustration
    Eliminate the need for multiple channel scan
    Takes the guesswork out of finding the towers
    Simple to use, plug-n-play design
    Connects to the antenna TV output or in-line
    Positive signal identification

    Specifications:
    Dimensions: 3.5"L x 3.2"W x 1"D
    Weight: .25 lbs

    VHF/UHF Frequency: 40-862 MHz (Ch 2-69)
    Signal Range: 60-90 dBuV

    Power Requirement: 5V DC, 40mA

    Battery: 9V PP3 Type (included)

    Warranty: 1 year - limited

    Kit Contents:
    Signal Meter
    9V PP3 Type ...
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