That used to be another option here, but now many of the larger ones like Goodwill and Salvation Army send a lot of electronics directly to the recycling center where they are scrapped.
We donated a bunch of stuff to the Salvation Army and when the guy with the truck showed up he had a Fender tube guitar amp on board from a previous stop. The truck driver refused a $50 bill saying that I needed to go to the store and buy it.
I went to their main store only to find that their policy dictates that all hazardous electronic stuff is sent to the recycling center. I went there to find that all the old stuff that their staff doesn't know how to handle goes to the landfill.
I received a PM and a couple of emails asking about ham radio licensing and ham radio in general. One person even wanted to buy my "extra" license. I still don't know if he was serious and not understanding, or joking, so....
Ham radio is a hobby where people can communicate over radio waves using voice, morse code, TV, and computer technology. It is illegal to transmit a radio signal over much of the radio spectrum without a license. There are specific radio frequencies available for use by ham radio operators who are licensed by the governing agency in their respective countries.
These frequencies and licensing requirements that vary by country, and change over time. I don't know much about the requirements for other countries, but in the US it currently goes like this.
Just a few years ago you had to know how to use morse code and travel to an FCC office to be quizzed by a government official before you would be allowed to operate ham radio equipment. All that has changed. Now you can show up at a hamfest, or radio club meeting when a "exam session" is being given and answer a 35 or 50 question multiple guess test, with a passing score. No morse code skills are needed.
A ham radio license is good for ten years and can be renewed forever if it has not expired. It is not transferrable and can only be used by the person it was issued to. There are 3 classes of licenses, technician, general and extra. The technician class license has a good amount of operating privileges and frequncies and has the easiest 35 question test. The extra class license allows the least operating restrictions on all available ham radio frequencies. It also has the hardest 50 question test. The general class is in between.
The test questions are about the rules and regulations (which frequencies and power levels you can use) and about radio and electronics technology. The test questions are randomly selected from a question pool that is specific to the license test that you are taking. Thus there are three different question pools.
The question pools are updated every year or so to remain current with the state of the art. The question pools ARE POSTED ON THE INTERNET IN ADVANCE! We called this cheating in school, That's right you can SEE the QUESTIONS and the ANSWERS in advance.
OK, how can you not pass this test......but wait there's more...there's an organization that makes up practice tests from the question pool that you can take online. Just keep taking the test, reviewing the questions that you get wrong, until you consistantly score in the 90% range, then go take the real test.
I printed out the test pool for the extra test and went over them all twice on two different days, highlighting the correct answers. Then I did practice tests for about 6 hours on the day of the real test, then went to the radio club meeting and passed the test.
I must admit that I am a radio design engineer so I had a little technical advantage.
The organization for promotion of ham radio is the ARRL. The question pools and a lot of ham radio info is on their web site:
Question Pools
The practice sessions are here (registration is required):
QRZ.COM Practice Amateur Radio Exams
Ham radio is a hobby where people can communicate over radio waves using voice, morse code, TV, and computer technology. It is illegal to transmit a radio signal over much of the radio spectrum without a license. There are specific radio frequencies available for use by ham radio operators who are licensed by the governing agency in their respective countries.
These frequencies and licensing requirements that vary by country, and change over time. I don't know much about the requirements for other countries, but in the US it currently goes like this.
Just a few years ago you had to know how to use morse code and travel to an FCC office to be quizzed by a government official before you would be allowed to operate ham radio equipment. All that has changed. Now you can show up at a hamfest, or radio club meeting when a "exam session" is being given and answer a 35 or 50 question multiple guess test, with a passing score. No morse code skills are needed.
A ham radio license is good for ten years and can be renewed forever if it has not expired. It is not transferrable and can only be used by the person it was issued to. There are 3 classes of licenses, technician, general and extra. The technician class license has a good amount of operating privileges and frequncies and has the easiest 35 question test. The extra class license allows the least operating restrictions on all available ham radio frequencies. It also has the hardest 50 question test. The general class is in between.
The test questions are about the rules and regulations (which frequencies and power levels you can use) and about radio and electronics technology. The test questions are randomly selected from a question pool that is specific to the license test that you are taking. Thus there are three different question pools.
The question pools are updated every year or so to remain current with the state of the art. The question pools ARE POSTED ON THE INTERNET IN ADVANCE! We called this cheating in school, That's right you can SEE the QUESTIONS and the ANSWERS in advance.
OK, how can you not pass this test......but wait there's more...there's an organization that makes up practice tests from the question pool that you can take online. Just keep taking the test, reviewing the questions that you get wrong, until you consistantly score in the 90% range, then go take the real test.
I printed out the test pool for the extra test and went over them all twice on two different days, highlighting the correct answers. Then I did practice tests for about 6 hours on the day of the real test, then went to the radio club meeting and passed the test.
I must admit that I am a radio design engineer so I had a little technical advantage.
The organization for promotion of ham radio is the ARRL. The question pools and a lot of ham radio info is on their web site:
Question Pools
The practice sessions are here (registration is required):
QRZ.COM Practice Amateur Radio Exams
Thats this Saturday by the way. Doors open at 9:00 as usual.
Really good hamfest/fleamarket
tubelab, in my experience it depends on who you speak to at the SA. If they aren't in position of authority they cannot do anything for you unless they can get approval. This January I was dropping stuff off and there was a set of early Klipsch Heresy speakers and a Carver receiver waiting to be processed. I asked the attendant when they would hit the sales floor and said in a few days. I replied I would miss them as I would not be able to return. He then did something that amazed me, he went inside and found the store manager. The store manager came out, looked at the items, and gave me a price. I went inside, payed, and left with them.
I have been going to hamfests for nearly 50 years. I have won several books, which I still have, a radio and an antenna, which I sold at the next hamfest.
For those on or near the east coast of Florida, the West Palm Beach hamfest is Saturday morning (Mar. 10) and the Stuart hamfest is the following Saturday (Mar. 17). Weather and work schedule permitting I plan to be at both selling tubes, transformers and other "stuff". Both are small shows on Saturday morning only.
Palm Beach County Amateur Radio Festival
Stuart Hamfest | Stuart Florida Hamfest
Went to a hamfest a few weeks ago and bought a handful of acorn tubes for $1 each along with a 9002. Also picked up a panel meter for $1 with a scale reading MILLIROENTGENS PER HOUR.
Years ago I bought a $10 box of tubes that had like 30 brand new 6080s and 30 other of some usless type, a hexagrid mixer or something. Tried to give them away for the cost of shipping but ended up throwing them away.
I tried building an OTL with the 6080s but the layout was sloppy and it had LF stability problems. After watching a few tubes pop I gave up. Later on people claimed that 6080s did that and 6AS7s worked much better. Oh well a lesson learned for clean layouts.
Years ago I bought a $10 box of tubes that had like 30 brand new 6080s and 30 other of some usless type, a hexagrid mixer or something. Tried to give them away for the cost of shipping but ended up throwing them away.
I tried building an OTL with the 6080s but the layout was sloppy and it had LF stability problems. After watching a few tubes pop I gave up. Later on people claimed that 6080s did that and 6AS7s worked much better. Oh well a lesson learned for clean layouts.
We are not only allowed to use those frequencies, we are also allowed to design and build equipment (receivers, transmitters, antennas,...) to operate on those frequencies.
We are also allowed to build our own equipment.
For years few people few people built anything since it was often cheaper and easier to buy a ready made radio. The maker movement has provided us with cheap processing power, which has started a small but growing group of Software Defined Radio builders.
I worked for Motorola as a radio designer for 41 years. That ended 2 years ago. Now that I am no longer bound by a restrictive employment agreement I will be working on a high quality ham transceiver.
For years few people few people built anything since it was often cheaper and easier to buy a ready made radio. The maker movement has provided us with cheap processing power, which has started a small but growing group of Software Defined Radio builders.
I worked for Motorola as a radio designer for 41 years. That ended 2 years ago. Now that I am no longer bound by a restrictive employment agreement I will be working on a high quality ham transceiver.
Just this last weekend I went to the Shelby NC Labor Day Weekend hamfest, supposedly one of the biggest on the east coast. It has been about a decade since I last went there, last time it was mindbendingly big and I found some great stuff (a bunch of NOS WE417A's for $2 each, a Lambda 71 power supply chock full of Telefunken ECC83's for $15). But last Saturday's was a huge disappointment, maybe less than half the sellers they had in years past. Almost no computer stuff at all. I bought two NOS tubes and some switches, $7 total.
One thing really stuck out; they are almost giving away CRT scopes these days. No surprise though, the newer LCD scopes are dirt cheap and extremely capable. My CRT scopes have all been gathering serious dust after getting a new Rigol.
If I'm not mistaken, wasn't part of the reason the US government supported ham radio in the past was for a ready made communications network that could partially survive a nuclear war? IIRC you had to agree to help the gov't to get a license. Not that there's anything wrong with that, just an interesting piece of trivia.
One thing really stuck out; they are almost giving away CRT scopes these days. No surprise though, the newer LCD scopes are dirt cheap and extremely capable. My CRT scopes have all been gathering serious dust after getting a new Rigol.
If I'm not mistaken, wasn't part of the reason the US government supported ham radio in the past was for a ready made communications network that could partially survive a nuclear war? IIRC you had to agree to help the gov't to get a license. Not that there's anything wrong with that, just an interesting piece of trivia.
US hams were not required to support govt radio services, but they (through MARS) were enticed to do so. Free or cheap military surplus, and at least in the 1960's, a few extra radio frequencies were available to those who signed up. There were military traffic nets that required periodic check ins usually to relay messages from overseas military personnel to their relatives back home. Remember the cell phone, the PC and the internet didn't get invented until the 80's.
Not "nuclear war" specifically but every event that disrupts (loss of power grid, damage of infrastructure,...) other means of communications. Let's quote Wikipedia:
Also think of the 2004 Tsunami or the earthquake in Haiti. That's the main reason why the ITU (International Telecommunication Union) still grants us our bands. Trivia: back in the day, those frequencies were considered useless for commercial use. Right now we have to constantly defend the privilege for certain bands. Notably the ISM-band (70cm), where we have priority status. The industry of course would love to get us out of that (and other) bands, but the emergency communications argument has kept us there.
To me, they are social events first - I get to see people in person, put a face with a callsign, see old friends, etc., - and second, a primary source of parts.
I haven't done it much in the last six or seven years, due to some business issues and then the arrival of the third harmonic. I've started taking him with me the last couple of years, but that puts a limit on range of travel.
I went to a local one a couple of weeks ago and came back with some Thordarson power transformers, one unused, loops of pvc insulated wire, more new 6CD6's and 6GB5's ( like I need any more, but seriously, at $0.25/each, why not, and when the four year old is in charge of the sack, not a crisis if a transformer crushes them ) tube sockets, 7 and 4 pin, and a real lucky strike - enough J.W. Miller permeability tuned RF coils to do a complete front end and reengage on that hybrid transceiver I've been diverted away from. $23 bucks total, I think.
The only tubes I'm really looking for are 801's and 10's, and a guy had a big box piled deep of unused ones, including some real nice ceramic based 10Y's that were marked Western Electric ( couldn't tell who actually made them ) but he wanted more than I was willing to pay for tubes that would just be for experimenting.
Win W5JAG
I haven't done it much in the last six or seven years, due to some business issues and then the arrival of the third harmonic. I've started taking him with me the last couple of years, but that puts a limit on range of travel.
I went to a local one a couple of weeks ago and came back with some Thordarson power transformers, one unused, loops of pvc insulated wire, more new 6CD6's and 6GB5's ( like I need any more, but seriously, at $0.25/each, why not, and when the four year old is in charge of the sack, not a crisis if a transformer crushes them ) tube sockets, 7 and 4 pin, and a real lucky strike - enough J.W. Miller permeability tuned RF coils to do a complete front end and reengage on that hybrid transceiver I've been diverted away from. $23 bucks total, I think.
The only tubes I'm really looking for are 801's and 10's, and a guy had a big box piled deep of unused ones, including some real nice ceramic based 10Y's that were marked Western Electric ( couldn't tell who actually made them ) but he wanted more than I was willing to pay for tubes that would just be for experimenting.
Win W5JAG
I hate to sound like a luddite, and I grudgingly acknowledge that this is the inevitable future, but the SDR rigs just leave me meh. The last new Yaesu I bought, admittedly in the lower end of the range, and already superceded by a new model, is all SDR behind the front end, and it just doesn't seem quite right. Dissatisfaction with that prompted me to buy the DZ radio about five or six years ago, and I got the full complement of filters for it, but I fear I'll never get around to actually building it. I have not looked at new HF radios since I bought the DZ.
I have sprung for an arduino and some SDR vhf radio chips , but I've yet to get interested enough to do anything more than blink an LED on and off. Is there a forum somewhere for this type of stuff?
Win W5JAG
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There are lots of things called SDR these days, and many believe that digitizing the RF as close to the antenna as possible is the future, but it can't be unless some radical new filtering technology is invented first, especially in the HF spectrum.
Consider the audio world, a 16 bit digital audio system has a theoretical dynamic range of 96 db, real world 80 to 85 db. A real world 24 bit system might see high 90's, despite those claims by some PC motherboard makers with on board audio specced at 105 db. This means that a signal will not be heard or even seen on an FFT plot if it is 90 db below the sum total of EVERYTHING else seen by the input of the A/D converter, hum, noise, aliasing artifacts, digital crud from the rest of the system, and other unwanted signals.
Now, stick an antenna on an A/D with a 100 MHz sampling rate and a 30 MHz filter. This will attempt to digitize the entire HF spectrum. There are SDR's on the market today that do exactly this. I bought one at Dayton maybe 10 years ago. It was nearly useless in south Florida because of the large amount of RF in the air.
The A/D was overloaded by the noise from the 768 KV power transmission lines across the street from my house. I could not receive ANYTHING with that radio. My Yeasu FT817 was also toast on 40 meters and below. I sold the SDR several years ago, but it would probably do OK here miles from nowhere.
The desired signal must be several db stronger than the sum of all other signals hitting the D/A converter for a successful demodulation of AM or FM. This is called the Signal to Noise ratio (S/N). SSB and CW need less S/N margin, and some digital modulation formats like LTE can work with near zero S/N.
For ANY radio to work in a high RF environment, there MUST be some filtering in front of the converters. If you want to tune the CW section of a band on contest day and be able hear the DX in the midst of the locals blasting out a KW or more......that filtering better be steep, and only a few hundred Hz wide. The dynamic range of everything in front of those filters better be as good as your converter.
I spent the last 30 years of my 41 year career at Motorola "defining the state of the art in two way radio design." The best hand held radio we made had a dynamic range of 80 db and the best mobile about 85 db. These are the latest technology, both new products, and still not good enough in certain locations and frequencies, like 865 MHz in a building with two cell towers right outside the third floor window on 880 MHz, or 469 MHz near a couple of 1 MW TV stations 20 MHz away from a weak repeater. The receiver is all analog up to the second IF.
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