Posts Tagged ‘HF’
Land (er, FREQUENCY) Grab (Part 1)
This article is part one in a multi-part series. Part 2 is located here: One Aspect of Amateur Radio: Good Will Ambassadors to the World. Part 3 is located here: In Response — Can’t We All Just Get Along?
We’ve all heard it at least once: no one owns a frequency.
By law, amateurs must keep the transmissions from their station within the bounds of the allocations granted to license-holding operators–within these bands that are allocated for amateur radio use. Amateurs are expected to follow band-plans, which guide us to which mode can be used in a band.
Subbands — Band Plans
There are many decades of constant refining of the standard operating procedures–perhaps we can call them, traditions–that, for the most part, work out pretty well for most amateur radio operations on our precious allocations in the radio spectrum. Each band–a slice of radio spectrum between a lower frequency and a higher frequency–is made up of subbands. These subbands are slices within a specific band (allocation), in which amateurs participate in two-way communications by using a particular mode of transmission, like single side band or CW.
For instance, Morse code enthusiasts use CW (continuous-wave modulation, i.e., A1A) between 14.000 MHz and 14.150, which is the subband that exists in the larger allocations known as the 20-Meter Band. The 20-Meter Band is 14.000 MHz to 14.350 MHz, and the regulating bodies (such as the FCC in the USA) have directed through law that voice modes cannot be used between those subband frequencies from 14.00 MHz to 14.15 MHz. Voice modes can be used from 14.15 MHz up to 14.35 MHz, with certain license class variations. Read the PDF from the FCC: FCC ONLINE TABLE OF FREQUENCY ALLOCATIONS
CW is not the only mode allowed in the 14.00-MHz-to-14.15-MHz subband. The regulations stipulate that a number of data modes can be used in this subband. There are specific requirements that a mode must meet, in order to comply with regulations–these are known as the authorized emission types.
Gentlemen’s Agreements
Amateur radio operators, decades ago, began discussing, then agreeing to, agreements between all operators as to where specific modes can be used, so those operating the different modes do not trample on each other’s transmissions. These agreements are known as our band-plan gentlemen’s agreements. They exist to help minimize interference–QRM–and to help foster good operating procedures between the different groups.
The band plans that have evolved through the decades are not regulations, and do not mean that any particular group of amateur radio operators own any frequency or subband. A mode does not own a particular subband. Amateur radio operators are not encouraged to start transmitting a mode that is typically found in that subband, if someone else is on that frequency using a mode not expected.
Just because some other operator is using the subband for a mode not in compliance with the gentlemen’s agreement, don’t purposefully try to eject that operator. At the same time, the gentlemen’s agreements exist to help amateurs avoid interference with others that are using different modes. Thus, the operator who has chosen to use a non-standard mode for a subband known to be used for some other mode should move that operation to the subband identified to be for that operator’s current mode of transmitter emissions. In other words, do not QRM another amateur radio operator, and do not cause confusion and frustration by barging into a subband for a mode that you are not intending to use. Use the mode expected in the subband of your current operations.
This concept is especially helpful when we consider weak-signal operations. If a very strong, loud teletype transmission begins in a subband that is set aside for weak-signal propagation modes like WSPR, then it defeats the efforts of the operators making the attempt to have successful weak-signal two-way communications. Thus, the teletype transmission should be made in a subband where teletype operation is expected and acceptable. And, WSPR should stay in the subband where people expect to find WSPR signals.
This concept is also applied to VHF or higher bands. Why? If repeaters are parked on known repeater subbands, then weak-signal single-sideband communications can take place in a subband where repeaters are not allowed. By allowed, though, I mean, by agreement with gentlemen’s agreements. Regulators have stayed out of the amateur radio operations except by creating regulations at a high-level–for instance, the FCC stipulating that voice communications are not allowed between 14.000 MHz and 14.150 MHz, in the 20-Meter band.
The Frequency Grabs by the WSJT Developers, Planners, and Leadership
With several current release candidates of the WSJT-X software by Joe Taylor, the group of developers and leadership have programmed into the WSJT-X software a set of NEW default frequencies. These new frequencies are in addition to their current pre-programmed frequencies that the amateur community now identifies as, The FT8 Subbands.
The new proposed frequencies are right on top of other subbands where other modes have been operating for decades (such as PSK and Olivia, and many others). There was no community discussion, except within the WSJT community. And, when someone protested the take-over of other well-established subbands, those protests were shot down. The stated reasons included, “Well, those other modes are not very active or popular, because spots are not showing up on various spotting networks.” Such reasons break down on deeper consideration–for instance, most spotting networks are not programmed to automatically identify Olivia transmissions. CW, PSK, and FT8 are programmed into scanners, but other modes are ignored.
This behavior, considered rude, arrogant, presumptuous, and anti-gentlemanly (referring to well-established gentlemen’s agreements) has happened before, with the initial release of FT8. They (the WSJT-X developers and leadership) simply picked a frequency slice of each subband, without true collaboration with the wider amateur radio community.
When this columnist and fellow amateur radio community member, attempted a discussion, the retort from an official representative was an absolute dismissal of any protest against the choice and method of frequency options within the WSJT software. While the software marks these frequency as suggestions, only, these defaults are used without question by the operators of said software. And, the mode is so fast that there’s no human way of truly monitoring the frequency before use, to see if some other mode is in operation. Besides, weak-signals that are present but cannot be heard by one’s ear, might well be in operation. Subbands exist to keep QRM from covering up the weak signals of the mode expected at that frequency.
Enter the IARU…
The IARU has decided to step in and join the discussion. “The International Amateur Radio Union has been the worldwide voice of radio amateurs, securing and safeguarding the amateur radio spectrum since 1925.” The IARU guides regulating bodies like the FCC, regarding the administration and rule-making pertaining to amateur radio.
The IARU states, on their website,
The radio spectrum is a priceless natural resource. Because radio waves do not respect borders, the use of the spectrum must be regulated internationally. This is accomplished through the International Telecommunication Union (ITU), a specialized agency of the United Nations. Through World Radiocommunication Conferences (WRCs) held approximately every four years the ITU revises the international Radio Regulations which have the force and effect of a treaty. The Radio Regulations allocate the spectrum to different radiocommunication services such as broadcasting, mobile, radar, and radionavigation (GPS). The most recent WRC was held in October-November 2019. The next one is not yet scheduled but is expected to be held in 2023, so it is usually referred to as WRC-23.
New uses of the spectrum are being developed every day. This puts enormous pressure on incumbent users who are called upon to share their spectrum access with new arrivals. The allocation process is extremely complex, especially when satellite services are involved.
Reportedly, from first-hand communication from one IARU representative,
WSJT-X RC3 has 14074 kHz again for FT8. IARU is intervening. Stay tuned. I am asking for further suggestions.
73 Tom DF5JL
IARU R1 HF Manager
This is very welcomed news!
What ought to take place, as quickly as possible, is to rally the different interested parties, like the Olivia group, the PSK groups, the various CW groups like CWOps, FISTS, and the SKCC, and many others, for ideas and suggestions. A discussion must take place in the hope that new gentlemen’s agreements can be made, that include the FT8 and FT4 operations, without stepping on the subbands of other digital modes.
As Tom says, STAY TUNED.
If you have suggestions, please comment. This columnist will summarize the main ideas of the comments and forward them to Tom. You may also contact the IARU managers and let them know your suggestions.
Discussions in the Olivia community are ongoing, too. Join in at OliviaDigitalMode.net even if you are not yet an Olivia operator.
On Facebook, you may also discuss your thoughts, in either the Olivia Digital Modes on HF group or in the Digital Modes on HF group.
If you use FT8 and FT4, voice your concerns and ideas, too. Open dialog, without declaring war, is welcomed and hopefully will prove productive.
This article is the first in a series focusing on band plans, and gentlemen’s agreements. Please stay tuned for more installments.
Tomas Hood, NW7US, is a regular contributor to AmateurRadio.com and writes from Nebraska, USA. Tomas is the Space Weather and Radio Propagation Contributing Editor to ‘CQ Amateur Radio Magazine’, and ‘The Spectrum Monitor’ magazine.
How Did You Fare in CQ WW CW Contest Weekend?
Man, lots and lots of Morse code on the ham bands, this weekend. The CQ Worldwide CW Contest weekend was hopping with signals!
How did you do this weekend? How were conditions on the various contest bands?
Comment here and your report may make it into the propagation column in an upcoming edition of the Radio Propagation column in CQ Amateur Radio Magazine.
Here are a few moments as heard at the station of the CQ Amateur Radio Magazine propagation columnist, in Lincoln, Nebraska (yeah, that’s me, NW7US).
[embedyt]https://www.youtube.com/watch?v=eWCbtIOJmLI[/embedyt]
Here are the results of my dabbling with the Icom rig and this contest:
NW7US's Contest Summary Report for CQ-WW Created by N3FJP's CQ WW DX Contest Log Version 5.7 www.n3fjp.com Total Contacts = 55 Total Points = 8,979 Operating Period: 2019/11/24 10:23 - 2019/11/24 22:51 Total op time (breaks > 30 min deducted): 3:58:46 Total op time (breaks > 60 min deducted): 4:45:17 Avg Qs/Hr (breaks > 30 min deducted): 13.8 Total Contacts by Band and Mode: Band CW Phone Dig Total % ---- -- ----- --- ----- --- 80 8 0 0 8 15 40 7 0 0 7 13 20 25 0 0 25 45 15 15 0 0 15 27 -- ----- --- ----- --- Total 55 0 0 55 100 Total Contacts by State \ Prov: State Total % ----- ----- --- 52 95 HI 3 5 Total = 1 Total Contacts by Country: Country Total % ------- ----- --- Canada 6 11 Brazil 5 9 USA 5 9 Argentina 3 5 Costa Rica 3 5 Hawaii 3 5 Bonaire 2 4 Cayman Is. 2 4 Chile 2 4 Cuba 2 4 Japan 2 4 Mexico 2 4 Aruba 1 2 Bahamas 1 2 Barbados 1 2 Belize 1 2 Curacao 1 2 Dominican Republic 1 2 French Guiana 1 2 Haiti 1 2 Honduras 1 2 Martinique 1 2 Montserrat 1 2 Nicaragua 1 2 Senegal 1 2 St. Kitts & Nevis 1 2 St. Lucia 1 2 Suriname 1 2 US Virgin Is. 1 2 Venezuela 1 2 Total = 30 Total DX Miles (QSOs in USA not counted) = 151,407 Average miles per DX QSO = 3,028 Average bearing to the entities worked in each continent. QSOs in USA not counted. AF = 83 AS = 318 NA = 124 OC = 268 SA = 137 Total Contacts by Continent: Continent Total % --------- ----- --- NA 32 58 SA 17 31 OC 3 5 AS 2 4 AF 1 2 Total = 5 Total Contacts by CQ Zone: CQ Zone Total % ------- ----- --- 08 13 24 03 7 13 09 7 13 07 6 11 11 5 9 13 3 5 31 3 5 04 2 4 05 2 4 06 2 4 12 2 4 25 2 4 35 1 2 Total = 13
Olivia Digital Mode (1000 Hz) on Twenty Meters – A Simple Video
The Olivia digital mode on HF radio is a mode capable of two-way chat (QSO) communication (keyboard to keyboard, like RTTY) over long-distance shortwave (HF) ionospheric propagation paths, especially over polar regions.
If you are interested in more than a logbook QSO (such as is typical with FT8 and other propagation-checking modes) but want to chat with other hams around the world using digital modes, consider Olivia as one option.
This video captures a few moments of two-way conversation on the Twenty-Meter band, up in the sub-band where 1000-Hz digital modes are commonplace. More narrow-bandwidth settings are used in a lower subband in the digital slice of Twenty Meters. More details about the mode are in the files section of this website: http://OliviaDigitalMode.org.
[embedyt] https://www.youtube.com/watch?v=FUjiBVsXrzE[/embedyt]
In 2005, SP9VRC, Pawel Jalocha, released to the world a mode that he developed starting in 2003 to overcome difficult radio signal propagation conditions on the shortwave (high-frequency, or HF) bands. By difficult, we are talking significant phase distortions and low signal-to-noise ratios (SNR) plus multipath propagation effects. The Olivia-modulated radio signals are decoded even when it is ten to fourteen dB below the noise floor. That means that Olivia is decoded when the amplitude of the noise is slightly over three times that of the digital signal!
Olivia decodes well under other conditions that are a complex mix of atmospheric noise, signal fading (QSB), interference (QRM), polar flutter caused by a radio signal traversing a polar path. Olivia is even capable when the signal is affected by auroral conditions (including the Sporadic-E Auroral Mode, where signals are refracted off of the highly-energized E-region in which the Aurora is active).
Currently, the only other digital modes that match or exceed Olivia in their sensitivity are some of the modes designed by Joe Taylor as implemented in the WSJT programs, including FT8, JT65A, and JT65-HF–each of which are certainly limited in usage and definitely not able to provide true conversation capabilities. Olivia is useful for emergency communications, unlike JT65A or the popular FT8. One other mode is better than Olivia for keyboard-to-keyboard comms under difficult conditions: MT63. Yet, Olivia is a good compromise that delivers a lot. One reason for this is that there are configurations that use much less bandwidth than 1000 Hz. 16 tones in 250 Hz is our common calling-frequency configuration, which we use lower down in the Twenty-Meter band, with a center frequency of 14.0729 MHz.
Q: What’s a ‘CENTER’ Frequency? Is That Where I Set My Radio’s Dial?
For those new to waterfalls: the CENTER frequency is the CENTER of the cursor shown by common software. The cursor is what you use to set the transceiver’s frequency on the waterfall. If your software’s waterfall shows the frequency, then you simply place the cursor so that its center is right on the center frequency listed, above. If your software is set to show OFFSET, then you might, for example, set your radio’s dial frequency to 14.0714, and place the center of your waterfall cursor to 1500 (1500 Hz). That would translate to the 14.0729 CENTER frequency.
The standard Olivia formats (shown as the number of tones/bandwidth in Hz) are 8/250, 8/500, 16/500, 8/1000, 16/1000, and 32/1000. Some even use 16/2000 for series emergency communication. The most commonly-used formats are 16/500, 8/500, and 8/250. However, the 32/1000 and 16/1000 configurations are popular in some areas of the world (Europe) and on certain bands.
These different choices in bandwidth and tone settings can cause some confusion and problems–so many formats and so many other digital modes can make it difficult to figure out which mode you are seeing and hearing. After getting used to the sound and look of Olivia in the waterfall, though, it becomes easier to identify the format when you encounter it. To aid in your detection of what mode is being used, there is a feature of many digital-mode software implementation suites: the RSID. The next video, below, is a demonstration on how to set the Reed-Solomon Identification (RSID) feature in Ham Radio Deluxe’s Digital Master 780 module (HRD DM780).
I encourage ALL operators, using any digital mode such as Olivia, to TURN ON the RSID feature as shown in this example. In Fldigi, the RSID is the TXID and RXID; make sure to check (turn on) each, the TXID and RXID.
Please, make sure you are using the RSID (Reed Solomon Identification – RSID or TXID, RXID) option in your software. RSID transmits a short burst at the start of your transmission which identifies the mode you are using. When it does that, those amateur radio operators also using RSID while listening will be alerted by their software that you are transmitting in the specific mode (Olivia, hopefully), the settings (like 8/250), and where on the waterfall your transmission is located. This might be a popup window and/or text on the receive text panel. When the operator clicks on that, the software moves the waterfall cursor right on top of the signal and changes the mode in the software. This will help you make more contacts!
RSID Setting:
[embedyt]https://www.youtube.com/watch?v=lBIacwD9nNM[/embedyt]
+ NOTE: The MixW software doesn’t have RSID features. Request it!
Voluntary Olivia Channelization
Since Olivia signals can be decoded even when received signals are extremely weak, (signal to noise ratio of -14db), signals strong enough to be decoded are sometimes below the noise floor and therefore impossible to search for manually. As a result, amateur radio operators have voluntarily decided upon channelization for this mode. This channelization allows even imperceptibly weak signals to be properly tuned for reception and decoding. By common convention amateur stations initiate contacts utilizing 8/250, 16/500, or 32/1000 configuration of the Olivia mode. After negotiating the initial exchange, sometimes one of the operators will suggest switching to other configurations to continue the conversation at more reliable settings, or faster when conditions allow. The following table lists the common center frequencies used in the amateur radio bands.
Olivia (CENTER) Frequencies (kHz) for Calling, Initiating QSOs
It is often best to get on standard calling frequencies with this mode because you can miss a lot of weak signals if you don’t. However, with Olivia activity on the rise AND all the other modes vying for space, a good deal of the time you can operate wherever you can find a clear spot–as close as you can to a standard calling frequency.
Note: some websites publish frequencies in this band, that are right on top of weak-signal JT65, JT9, and FT8 segments. DO NOT QRM weak-signal QSOs!
We (active Olivia community members) suggest 8/250 as the starting settings when calling CQ on the USB frequencies designated as ‘Calling Frequencies.’ A Calling Frequency is a center frequency on which you initially call, ‘CQ CQ CQ. . .’ and then, with the agreement of the answering operator, move to a new nearby frequency, changing the number of tones and bandwidth at your discretion. Even though 8/250 is slow, the CQ call is short. But, it is narrow, to allow room for other QSOs nearby. It is also one of the best possible Olivia configurations for weak-signal decoding.
Opinions About ARRL Petition to FCC: Expand Technician HF Privileges!
In this video, I expound on another point of view regarding the ARRL petition to the FCC. The petition requests an expansion of operating privileges of Technician-class operators in the USA. The ARRL believes that giving broader shortwave access, using digital communications, to Technicians, will better entice the Techs to upgrade to General or Amateur Extra. In this video, I discuss this a bit.
If you are wondering why I’ve made a few videos about this topic, when the topic has been the hot item on many forums already, I believe that the drama will not cease until well after the FCC makes a decision, because this is a relevant topic, and one that has a significant impact on the amateur radio community at large. It is not a trivial conversation about which type of coax is best suited for Arctic field activity.
After some replies came from various viewers, I clarify my point. I stand corrected.
I failed to mention that there are a limited few slices of VOICE (SSB) spectrum on HF that the petition seeks for the Tech licensee. The ARRL states, “ARRL has asked the FCC to expand HF privileges for Technician licensees to include limited phone privileges on 75, 40, and 15 meters, plus RTTY and digital mode privileges on 80, 40, 15, and 10 meters.”
More specifically, “ARRL proposes to provide Technician licensees, present and future, with phone privileges at 3.900 to 4.000 MHz, 7.225 to 7.300 MHz, and 21.350 to 21.450 MHz, plus RTTY and digital privileges in current Technician allocations on 80, 40, 15, and 10 meters. The ARRL petition points out the explosion in popularity of various digital modes over the past 2 decades. Under the ARRL plan, the maximum HF power level for Technician operators would remain at 200 W PEP. The few remaining Novice licensees would gain no new privileges under the League’s proposal.” Reference: http://www.arrl.org/news/arrl-requests-expanded-hf-privileges-for-technician-licensees
My point holds: give some reason to desire to upgrade to a higher class. Do this by granting HF operations on lower bands (lower in frequency than 10 Meters), with more than a CW-only privilege.
If a tech can only use CW on 80m, but doesn’t know CW, then it is likely she won’t ever try making contacts on 80m. Hence, no exposure to the magic of 80-meter DX. If, however, the Tech can dabble with digital or limited SSB, on 80m, then she gets a real, practical exposure to the magic, and may well upgrade. Why do you think a General, who has limits, would ever upgrade? What am I missing here?
The following video expands this idea:
[embedyt] https://www.youtube.com/watch?v=83I3EEQxfZA[/embedyt]
The truth is, I see a strong argument for just ONE license, permanent. Or a temporary entry-level training ticket, then the permanent. But, that would make us like some other countries. That can’t be good.
The original video to which this new video continues is here:
[embedyt]https://www.youtube.com/watch?v=BWSAvDWE3Js[/embedyt]
Some viewers are asking me why I am making a video while driving. They try to convince me that talking while driving is too distracting. My answer is here:
[embedyt]https://www.youtube.com/watch?v=pyNHKViyCGE[/embedyt]
73 de NW7US
Travel Footage: 3Y0Z Antarctic Bouvet Island DXpedition 2018 Expedition (by EY8MM)
Here is video footage of the journey to Antarctic Bouvet Island, made by the 3Y0Z amateur ham radio team. This footage caught a few moments on the deck of M/V Betanzos.
As you can see in the last moments of this footage, the weather conditions contributed to the decision to abort the DXpedition, as it was far too dangerous to continue this expedition.
As reported by ARRL:
“Our captain has decided that it is in the best interest of safety and expediency to proceed directly to Capetown, South Africa, rather than Punta Arenas, Chile. We are now heading north to avoid the possibility of encountering ice. Currently, there is no ice in sight or on radar. In due time, we will head easterly toward Capetown. Our entire team is safe. Most are resting in their bunks and in good spirits. We will keep the amateur radio community and our families informed, as we continue our journey.”
In a huge disappointment for the DX community and the members of the 3Y0Z Bouvet Island team, the DXpedition’s leaders announced at 2000 UTC today (February 3) that a decision had been made to abort the DXpedition and head back to Chile.
“During the last 72 hours, we continued to experience the high winds, low clouds, fog and rough seas that have prevented helicopter operations since our arrival at Bouvet,” said an announcement on the 3Y0Z Bouvet Island website. “No improvement was predicted in the weather forecast for the next 4 days. Then, last night, an issue developed in one of the ship’s engines. This morning, the captain of the vessel declared it unsafe to continue with our project and aborted the DXpedition. We are now on our long voyage back to Punta Arenas. As you might imagine, the team is deeply disappointed, but safe. There is already talk about rescheduling the DXpedition.”
Bouvet Island currently is the third most-wanted DXCC entity, behind Kosovo and North Korea. The 3Y0Z DXpedition, comprised of top operators with considerable DXpedition experience, has been in the planning stages for 2 years and had attracted contributions from clubs and individuals around the world.
A dependency of Norway, Bouvet is a subantarctic island in the South Atlantic. The last Bouvet activation was 3Y0E, during a scientific expedition over the winter of 2007-2008.
Video Author: Nodir Tursun Zade, EY8MM
This copy is used BY PERMISSION from EY8MM, given in writing on 23 February 2018
Let’s Call CQ – QSO Today Episode 184 with NW7US
I got a Skype call a few weeks ago from Eric, 4Z1UG–the creator and host of the QSO Today Podcast–during which he asked me about how and why I got into amateur radio. Here’s the result.
Eric writes,
We talk a lot about the band conditions due to the Sunspot cycle. Most of it on Facebook and other places is about how “dead” the bands are at this point. We all can’t wait until the cycle starts to rise and we will be making contacts with little effort. I remember in my conversation with Chuck Adams, K7QO in Episode 58, that he really enjoys operating is “Pigrig”, one watt, CW transceiver on 20 meters. When I asked him, (I liberally paraphrase) “but Chuck, the bands are dead. How does that work for you?”. His reply was that while most hams are listening to the bands, he calls CQ until he gets a reply. Works every time.
My QSO this week is with Tomas Hood, NW7US, who has years of expertise in propagation and Solar activity. He is the propagation editor of more than a few radio magazines and websites. In our post-recording conversation we discussed this phenomenon of listening and not calling CQ. I even had this idea that maybe one of the reasons that the digital modes are so successful is because they “beacon”, as part of the whole digital experience, the same as calling CQ. This is why they make contacts. From what I see, looking at PSK Reporter, hams are making lots of contacts worldwide using the digital modes. While SSB may not be working so well, CW and the digital modes seem to work fine.
I like to work on my bench or make the podcast while listening to the bands. Jeff Damm, WA7MLH, in Episode 177, says that he will put his keyer in CQ mode while he is working on a new radio. Invariably, sometimes after many minutes, he gets a reply. Great idea Jeff!
73,
Eric, 4Z1UG
Episode 184 can be found here: https://www.qsotoday.com/podcasts/nw7us
Highlights of Episode 184:
Tomas Hood, NW7US is the propagation editor of a number of shortwave and amateur radio magazines, and has a wide variety of websites, that grew out of his love for all things radio, and for listening on the bands to far off DX and commercial broadcast stations. Tomas shares his understanding of propagation and the lessons we can learn from listening, really listening to the QSOs and exchanges during contest operation.
All of the QSO Today episodes are great. I enjoy hearing about many different hams. Do check out all of the episodes that Eric has published.
73 de NW7US dit dit
What Got You Interested in Radio? What Hooked You? (Story Time, with Video)
What got you interested in radio? What hooked you?
I’ve been asked, “What got you interested in radio, space weather, and the science of radio-wave propagation?”
Here’s a short answer as to why (and when) I became a radio enthusiast. It all started…
[embedyt] https://www.youtube.com/watch?v=0XBth62JgwA[/embedyt]
https://www.youtube.com/watch?v=0XBth62JgwA
The following picture is of my first shortwave radio, discovered in my home sometime between 1971 and 1973: a Sony portable transistorized four-band radio receiver. This was my very first shortwave radio (well, truthfully, it was my dad’s). This radio is responsible for my love of radio, electronics, and communications.
I still use this, sometimes, when listening to late-night AM-broadcast-band-radio DX. It is horrible for shortwave radio listening, as it has no noise blanker. For MW (Medium-wave) AM Broadcast DXing at night, it is excellent. The internal bar antenna is very directional so I can rotate the radio around until I get the best reception of some station. Back when I was a child, that made the radio very fun to use.
This next radio is a really capable military surplus radio circa WWII or shortly after (the late 1940s, early 1950s). This radio was my world starting around 1975. From Medium-wave to Shortwave, this radio could hear a pin drop around the world! Many late nights when I was supposed to be sleeping, I was up with the light dimmed and the tubes singing signals from exotic places.
What is your story?73 de NW7US
Addendum:
https://www.youtube.com/watch?v=y8bBM9Dy38o
[embedyt] https://www.youtube.com/watch?v=y8bBM9Dy38o[/embedyt]