Ham Radio Kits
how to convert a 40meter ham radio receiver into a 80 meter receiver?
how to convert a 40meter ham radio receiver into a 80 meter receiver,
I have a kit to make a 40 meter ham radio receiver, they 80 meter receiver has been discontinued, I hope there is someone who could give me a little bit help.
the kit is a 40 meter direct conversion receiver it uses a sa602 chip, two varactor diodes and two toroid ferrite coils that are hand wound.
Dear Jimjuta,
Direct conversion receiver is oldest type of receiver that designed before superheterodyne receiver system. In direct conversion, joined carrier signal and AF signal directly extracted/filted to get AF signal. While in superheterodyne system, joined carrier and AF signals, first developed to get IF (Intermediate Frequency) signal. This IF signal then amplified in order receiver to be more sensitive, then as final result: AF (Audio Frequency).
Superheterodyne developed because IF amplifier which frequency is much more low than RF, is easier to designed.
If you like to change frequency of your receiver, you should be able to modify oscillator/local oscillator of your receiver. Oscillator developed from many models: with LC tank, VCO, Crystal, etc..
Eg. oscillator with LC tank: main formula for resonance frequency: Fr=1/(2π√(LC)) . If values of L and C increased, resonance frequency would be lower. Of course if you modify oscillator, you would need oscilloscope which maximum frequency measurement is approximately 5MHz (because 80m band is between 3.5-3.9MHz).
In order to modify, you should understand internal circuit of SA602, so please download this link (just click): http://go2.wordpress.com/?id=725X1342&site=frrl.wordpress.com&url=http%3A%2F%2Ffrrl.files.wordpress.com%2F2008%2F11%2Fne602.pdf although this is datasheet for SA602A. On that datasheet, figure 7 shows various tuning circuits attached to pin 6 and 7, and figure 8 shows circuit if you are using VCO with synthesizer. I do not know what circuit you are using. SA602A could produce oscillation up to 200MHz, so modify it to 3.5-3.9MHz, I hope is alright.
I could recommend You good book to design oscillator: “Transistor Circuit Design With Experiment” by Delton T. Horn, and another good book to design coil/L/inductor: “ARRL Handbook”.
Have a nice experiment.
Thank You very much Jimjuta.
Emergency Amateur Radio Communication Kit by KH7O
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Aoyue 937+ Digital Soldering Station $45.99 This is a 45 watt digital soldering station that has a 1 degree C control. Features: ESD Safe Package content: 937+ station, B001 Soldering iron, 2630 Soldering iron holder, C001 Soldering iron spar… |
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Pyramid PS3KX 3-Amp 12-Volt Power Supply $22.41 Pyramid Car Audio PS3 AC Power Supply PS3 Power Supplies… |
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Solarcon I-MAX 2000 CB/Ham Radio Base Station Vertical Antenna – 24′ $96.01 Solarcon IMAX-2000 24ft Omni-Directional Fiberglass Base Station Antenna 5000 Watts…. |
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60 (1.5m) WiFi Pigtail N-type Male to RP-TNC $9.95 Ultra Low Loss Cable is designed to transmit the maximum signal to your antennas. LMR-240 cable by Times Microwave USA meets Military Specifications with silver foil and silver coated copper conductors for less signal loss in runs up to 200 feet.. In this high quality cable, the dimensions and spacing of the conductors are uniform. Any abrupt change in the spacing of the two conductors along the c… |
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Midland XT511 22-Channel FRS/GMRS Two-Way Emergency Crank Radio $89.99 Midland’s XT511 is a durable GMRS emergency crank radio with a wealth of features to keep you informed, charged up, and in contact no matter the situation around you. Stay in touch no matter your environment. Dynamo crank allows recharging of batteries without access to electricity. Built-in flashlight and USB port for charging your cell phone or other device… |
Ham Radio Satellite Software
AO-51 Satellite with USRP and WBX
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Handheld Deluxe VHF/UHF Dualband Amateur Radio 2M/440 Transceiver with Twin Display 5W TYT TH-UVF1 $99.99 New TH-UVF1A Dual Band, Dual Display, Dual Standby VHF-UHF 2M/440 deluxe Amateur Handheld Ham radio Transceiver! * It Features a receive range of 87-108 FM Broadcast, plus 136-174Mhz & 390-520Mhz! * Transmits full Ham Bands of 144-148Mhz & 430-450Mhz. (Optional 136-174 & 420-490 for Auth Part 90 users). * Direct Keypad entry, VOX, Tone Scan, Voice prompts, FCC Approved. * 3 selectable colors f… |
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Yaesu VX-3R VHF/UHF DualBand Handheld Amateur HAM Radio Tranceiver! $219.98 Super micro sized Yaesu VX-3R Amateur Ham Radio transceiver handheld. Transmits the 2 meter & 70cm Amateur Ham bands (1.5w/1w), & receives 0.5-999Mhz (less cell). Features 1,000 AlphaNumeric scanning memory channels, ARTS, WIRES, ctcss/dcs (PL & DPL). With an Optional Yaesu DC Adapter, Power output increases to 3W/2W. Transmits VHF/UHF Amateur radio bands, & receive shortwave, police, CB, Aircraf… |
Ham Radio Nation
Find Secondhand Ham Radios Through Your Local Ham Radio Club
If you are just starting in the amateur radio hobby, and it is your hope to become an operator, then you need to know a few things before rushing out and buying the 1st used ham radio you discover. You are going to need to read up on
take into consideration] is checking which frequencies and radio wavelengths are going to be reachable in your country and region. The frequencies of admittance can vary from country to nation, so you are going to need to make a point that the ham radio that you purchase will allow you to access the frequencies that are accessible in your region or state. It would be a lousy result if you went out and spent a bundle of money on a used ham radio that didn’t work in your region, this would make it absolutely purposeless unless you were to move to a new residence someplace else later in life.
Finally, you are definitely going to wish to get into contact with your local ham radio operators club. Most of the local clubs will open their doors freely to newcomers to the hobby, and it is normally pretty simple to find someone who will help you to understand the differences between the assorted secondhand ham radios for sale. They can likewise help guide you through the laws and frequencies open in your country making it simpler for you to figure out which secondhand ham radios are best for you.
If you are looking for shops that have ham radio on hand signs, you might have to look a little harder because despite the fact that 6 million individuals across the world are recreational radio operators, they are not devices that you commonly run into. Most of the time your best shot at getting a ham radio for sale that will work in your area is within your own realm because they are for sale from other people who have utilized them in the same frequency zone.
You are going to find that the largest obstacle to getting the right ham radio for you is the problem of the frequencies and wavelengths, as they differ from each geographic region and every radio is set to be able to obtain a certain set of frequencies. The same is true of country types as well, so if you have an purpose of communicating directly with individuals in a distinct country that is not your own you will have to do even more research before buying the 1st ham radio for sale that you come across.
In order to obtain a ham radio that really works the way that you visualize it to is to speak to your local ham radio club.Most of the “members” of local ham radio clubs will be very knowledgable about the theme and will give you good advice on the radio that you are looking for as well as possibly discovering that perfect ham radio that will fit you needs. Plus, you can start to build contacts and mentors which will make you more prosperous overall as a ham radio operator in the future.
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Ham Radio Nation – Intro
Antenna Rotor Cable
What is the best antenna rotor?
My antenna and rotor were hit by lightning. I'm in the process of selecting a rotor, but every time I find A-line that sounds good, the bad reviews I read. It seems that I can not get all those brains, because the majority of the population has about Cable or satellite. The one I had was 11 years old and no longer available.
Channel Master makes a good, that cheap: http://www.warrenelectronics.com/antennas/9521A.htm
DIY Coat Hanger Antenna reception video in CALGARY! 2009 OTA DTV Over the Air DIY coathanger
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VH127N Standard Power Cord $18.94 Audiovox VH127N Standard Power Cord VH127N 711… |
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RCA VHW111NV White RG-6 Coaxial Cable With Ends (100 feet) $12.40 Depend on this cable to provide you with a reliable audio/video connection between components…. |
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Philips/Gemini SWV2167W/27 Coaxial Cable $12.52 RG6 cable, connects TV, video, cable, and antenna components. 75 ohm. Black. UL listed. (UL100), 100′…. |
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Audiovox 100′Blk Rg6u Coax Cable Vhb6111n Antenna Wire(Co-Ax Flat Rotor) $12.92 100′, Black, RG6U Coaxial Cable, With “F” Connectors On Both Ends. For Satellite Systems & Use Behind Interior Walls, UL Approved, Made In USA…. |
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Sewell Vortex HD Digital Outdoor HDTV Antenna with Remote Control, Amplified and Motorized 360 Degree Rotation, UHF/VHF $17.95 Take advantage of free HD TV signals with the Vortex HD antenna made by Sewell which can pick up over-the-air HD signals from up to 125 miles (depending on obstructions and the topography of your area). Compatible with all TVs and HD signals Whether you live in a big city our out in a rural area, chances are you have free available HD signals being broadcast in your area. All you have to do is g… |