QRP2004 Build day 1

Here starts the log for the build today easy first day.I'm creating the PCB and my process is to use press and peel film (Maplin AB15R) so I use the REVERSED images of the CU layer you can obtain either from the qrp2004 project team website (http://myweb.tiscali.co.uk/qrp2004/) or the yahoo group (http://groups.yahoo.com/group/qrp2004/files/) Printer is a laser doesn't work with an inkjet printer, Samsung ML-2240...

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How to make a CW QSO

The original site at http://zs6ez.za.org/tutorial/cw-qso.htm has disappeared so I post that page here for reference for those trying to get started in CW.A search for zs6ez on QRZ:Born 1964, licenced 1980 as ZS6BCR. I've basically been inactive since 2000, due to other commitments. I hope to resume some ham radio one day. My main interest was in contesting, where I held several world and continental records...

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http://m1ktaipodamateurradio.blogspot.com/

Started something new todayhttp://m1ktaipodamateurradio.blogspot.c...

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2012 AWA Bruce Kelley QSO Party

The last two weekends I participated in the AWA Bruce Kelley QSO. Except for curious visitors, transmitters must be limited to 1929 (or earlier) designs and not crystal controlled.This year I used my Hull Hartley at 10 watts input and a Drake 2B receiver. The change from last year was having a 80 mtr vertical available rather than a simple...

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QRP2004 Build

I have had a few questions about this project ( http://groups.yahoo.com/group/qrp2004/ for details) so I will start a build from scratch and blog it here starting in the new year (i.e. 2011).This is the designed polyphase network for the QRP2004Copyright © 2004 - 2005 by QRP2004 Design TeamThe project design team include details of the design...

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JT65-HF - remarkable!

I've been using Joe Taylor's weak signal modes for a while now, mostly WSPR, but recently my attention has been drawn to an interesting spin-off which calls itslelf "JT65-HF".Clearly many people have been there before me, as there is quite a bit of activity in this mode, which seems to be able to produce quite remarkable and astonishing results.Having downloaded the software, set it up (easy peasy) and left it running for some...

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RF Decibel Meter

In any radio workshop, an RF decibel meter or power meter is an important instrument. Unfortunately, home-constructed ones are generally not sufficiently sensitive and/or are very temperature-dependent. These drawbacks are overcome by a device from Analog Devices which has recently become available: a low-cost DC–500 MHz, 92 dB logarithmic...

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80 Mtr Vertical Performance

I wondered if my 80 mtr top loaded vertical is a good antenna for the Bruce Kelley Memorial 1929 CW QSO Party. Part of the loading is the top 6' of two of the guys. Any sway at all causes a guy to sag a little shifting the load my Hartley sees. This causes my signal to FM/wobble...distracting to say to least and aggravating if the band is...

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Mag Loop

Just posting this as not QRT.The WX here in Mechelen (Belgium) had been snowing for the last week. So I have taken a mag loop antenna built by Clive (M5CHH) (from G4TPH design) I have put it up suspended in the open door way out to the patio.I determined that the door was 100% uPVC not metal framed and there does not appear to be any chnage...

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Broadband PLL FM Transmitter 88-108 MHz

Here's a simple FM transmitter design. It uses pll circuit from Motorola MC145170. This PLL includes the prescaler and a serial standard bus called SPI. We advise to use the P2 version that fixes some init issues during the Power Up.PLL FM SynthesizerThis PLL circuit is definitely smaller than the old one, consequently we've added on the...

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ROPOCO SSB - a selfish rant

I will be the first to admit that this is a very selfish point of view, but I really am quite annoyed (well as annoyed as I will allow myself to be over something which is a hobby/leisure activity) that the "powers that be" whoever they are, have turned one of the twice-yearly ROPOCO contests from a CW challenge to an SSB or phone one.Especially ROPOCO1 (April) in which I have previously participated many times.I am not a contester...

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2 Channels RF Remote Control-Transmitter Receiver

This RF remote control is useful to handle some electric device. If you want to control your garage door, the only way is to use some RF remote control. The transmitter-receiver circuit use few components and ordinary. It's easy to build it because you don't have to tune-up any coil or variable capacitor. The RF modules are fix to work in...

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8W Broadband RF Amplifier 2SC1971 88-108 MHz

Here's a broadband FM RF amplifier using 2SC1971 VHF power transistor. The RF Amplifier PCB layout designed for FM broadband 88-108 MHz using microstripline technique. This 8W RF amplifier circuit provides an appropriate power boost with an input of 500 mW.RF Amplifier PCBThe PCB outline is 77 x 56 mm use FR-4 double sided photoresist epoxy...

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Classic RF Probe using 1N34A Diode

One of the handiest accessories you can have around the shack is RF Probe. It can be used to measure RF voltage (and power), trace RF signals in a new design, and troubleshoot malfunctioning RF circuits. This RF probe is easy to build.Complete Classic RF Probe SchematicFor best probe accuracy, size the resistor to match your DC Voltmeter's...

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BAS70 RF Probe Circuit

This RF probe is useful for small RF power levels up through the microwave frequency bands, and simply connects to your DVM (Digital Volt Meter). The voltage shown will not be accurate, since this is a rectifier probe (diode probe), but the measurements are good enough for you to be able to determine where the RF stops, or if a stage is...

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4 Ports Power Splitter 2.4 GHz

Here is a device called a power splitter (divider/combiner). You can use this to phase four antennas together for increased gain or combine the input/outputs of amplifier for increased power.This 4 to 1 (4-1=4 ports) power splitter work at 2.4GHz. You will use it for stack 4 pieces of 2.4 GHz helical antenna for get 6 dB more gain on AO-40...

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RF Field Strenght Meter with Attenuator up to 200 MHz

The RF field meter unit will be in great help to tune transmitters for best performances. You can measure the radiated energy field and can easy tune the system for max output field strength (maximum power).RF Field Strength SchematicThis field strength meter with selectable attenuator. You can used it for measuring the antenna gain and pattern,...

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100W RF Power Amplifier 50 MHz 2SC2782

This is a 6m band RF power amplifier (50 MHz) with 100W output. It used with my FT-736R and drive from 10W for the 6m SSB DX. The Building information comes from Japan CQ Magazine. The Toshiba RF bipolar power transistor will be used in it. RF Power Amplifier Schematic and PCBGroundingIf you want to construc this rf amplifier, it's the better...

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80W RF Amplifier 2SC2782 88-108 MHz

This is a RF power amplifier design using 2SC2782 bipolar transistors in a tuned class C circuit. The amplifier can be driven to full power with less than 1 watt driving power, so that a large gain margin results in this FM transmitter.To obtain stability in this rf amplifier, I employed several techniques, such as placing the resonances...

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