Tag Archives: Guest Post

Kostas explores an alternative to Morse Code that’s been used in prisons, with roots in ancient Greece

Many thanks to SWLing Post contributor, Kostas (SV3ORA), for sharing the following guest post which originally appeared on his radio website:

TAP: A Morse alternative mode for the HAM, with no need for training

by Kostas (SV3ORA)

Introduction

The thinking of this new mode, came to me when someone posted that he quit the HAM hobby because he did not learn Morse code and he did not want to use computers to do the job for him. Some time I faced a similar situation and I believe many do one day or the other. So I thought that I had to do something about it. It is too bad people quit the hobby or missing the fun of the KEY operation, because of the obstacle of Morse code. No matter what CW operators that already learnt Morse might say, the fact is that Morse requires patience, continuous practice and most importantly time. After all military had dedicated courses on it in the past, so it must be more than true. These are things not all people can, or are willing to do. An alternative that gives the same pleasure like Morse and operates with the same techniques, but requires no training and time must exist. Meet the TAP mode!

Mode description

This mode has its roots to ancient Greece. You may read the article in Wikipedia for more information on the Polybius square. A form of it, was used in the previous century in was times, for in-prison communication. A modified version is presented here by me, that fits perfectly the HAM radio. This modified TAP code scheme, is dedicated to HAM radio and includes the numbers and the letter “k”.

This is all you need to know in order to send and receive TAP. It is easy to follow and easy to generate on paper. This is a 6 by 6 table, with the first six alphabet letters placed in the first line, the next six in the second and so on. After the alphabet ends, the numbers are put in the same manner. Thats it!

Sending TAP

It is better to describe the sending procedure with an example.
To send the letter “i” you send two dots (“i” is on the second row), wait a bit and then send 3 more dots (“i” is on the third column). In other words, you first count the number of rows where the letter exists, then wait a bit and then you count the number of columns where this letter exists. Before sending the next letter, leave a bit of more time, so as to distinguish that this is a separate letter and not the time between rows and columns. Thats it!

Try it now without any transceiver! Write the TAP table on a piece of paper (you do not need to write the row and column numbers), or read it from the website. Tap on your desk with your finger and send some words to the colleague near you. See how easy it is?

There are actually four spacings involved. The spacing between adjacent dots, the spacing between the row and the column, and the spacing between letters and the spacing between words. Follow the PARIS spacing, like Morse code does, if you intent to write a software for it. However, in practice, manual operators would need to consider just two spacings, the spacing between rows and columns and the spacing between letters. These are the most important. Just make the one bigger than the other and communication should be achieved without problems.

Receiving TAP

It is better to describe the receiving procedure with an example.
To receive the letter “i” you listen two dots (“i” is on the second row), then a short scilence time and then listen 3 more dots (“i” is on the third column). In other words, you first listen for a number of dots (this is the row where the letter exists), then sense the scilence and then you listen for the next number of dots (this is the column where the letter exists). The scilence time between two letters is greater than the scilence between rows and columns and this can be distinguished easily. Thats it!

Try it now without any transceiver! Write the TAP table on a piece of paper (you do not need to write the row and column numbers), or read it from the website. Put your coleague to sent you some TAP words and you should be able to decode them by counting the rows and columns in the TAP table.

A programmer that may need to implement the mode in software, should follow the PARIS spacing to distinguish the different parts of the code, as described above.

TAP advantages

Here are some advantages I can think, of TAP in comparison to Morse.

No training is required, start using it imediatelly, even by non-HAM people and kids. This probably is the greatest advantage and this is why most would want to use TAP in HAM radio.
The encoding/decoding square can be drawn easily, it is very easy to remember how to draw it.
Decoding by hardware or software means, becomes very easy, as there are no dashes to account for. Dot lengths can be anything and can be even varying from dot to dot, it does not matter.
All you count, is how many ON-states (taps) there are and the rough timing between them, to decide between a row-column or a letter. Because of this intependency from dashes, the code can be used on any means, radio, light, pipes, walls, desks etc.
If dot lengths are kept very short (up to the point where channel noise allows it), RF amplifiers can be pushed beyond their limits (due to limited duty cycle), or otherwise run cooler within their limits. There are some mediums, like light communication, where bright pulses of light can be produced easily (eg. xenon tubes), but not kept for duration and TAP is ideal on them.

TAP disadvantages

Here are some disadvantages I can think, of TAP in comparison to Morse.

Speed limit issues probably. TAP beginners achieve for sure faster speeds than Morse beginners. However, a trained Morse HAM, can achieve greater speeds with Morse.
Learning the table by heart, can be tricky in comparison to Morse. However war prisoners had tricks to learn by heart the 5×5 TAP square.
Not known (yet) among the HAM community, like any new mode. Why not change that by let HAMs know about it?

TAP common points to Morse

There are some common points shared between TAP and Morse code.

Both are relatively slow modes.
Both are ON/OFF keying modes, efficient class-E amplifiers can be used.
Both share the same channel bandwidth and noise-related characteristics.
Both are human-oriented, although TAP does not require training. Both share the PARIS timing when implemented in software.
Both allow for the “joy of the KEY”. You send TAP with the same equipment as Morse.
Both are ideal for homebrew QRP, due to efficiency and transceivers simplicity.

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You and the ionosphere: Share your propagation stories!

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Many thanks to SWLing Post contributor, Jock Elliott, who shares the following guest post:

You and the ionosphere . . . a reader participation post

By Jock Elliott, KB2GOM

Here’s a shocker for you: we live at the bottom of the sky. Above us there are multiple layers of the atmosphere, pressing down on us at 14.7 pounds per square inch.

Of particular relevance to us as shortwave listeners and hams, there is a special layer of the atmosphere, not shown on the chart above called the ionosphere. The ionosphere starts around 30 miles above us and extends up to about 600 miles and includes parts of the layers above.

The Sun’s upper atmosphere, the corona, is very hot and produces a constant stream of Ultra-Violet and X-rays, some of which reach our atmosphere. When the high energy UV and X-rays strike the atmosphere, electrons are knocked loose from their parent atoms and molecules, creating a layer of electrons.

Now, here’s the cool part: this layer – the ionosphere – is important because radio waves bounce off of it.

The sun, however, is not constant in its action on the ionosphere. The amount of UV and x-ray energy (photon flux) produced by the sun varies at by nearly a factor of ten as the sun goes through an 11 year cycle. The density of the ionosphere changes accordingly, and so does the ability of the ionosphere to bounce radio waves. When the sun is at peak activity, and the ionosphere is “hot,” SWLs and hams are likely to experience excellent long-range propagation. When the sun is quieter, long-range propagation diminishes.

Every 11-year solar cycle is unique, but early indications are that we may on the verge a cycle that favors long-range propagation: https://swling.com/blog/2022/03/termination-event-may-indicate-solar-cycle-strength/

The results can be spectacular. Decades ago, during a particularly hot solar cycle, I once spoke from my station near Albany, NY, to a station in the state of Georgia on a mere 4 watts. On another occasion, I conversed with a ham in Christchurch, New Zealand – a distance of over 9,000 miles – with 100 watts single sideband transmit power. During that same period, I would routinely listen to shortwave stations halfway around the world.

And now, it’s your turn – what’s your favorite long-range propagation story, either as an SWL or ham? Please comment!

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The conclusion to “Off the Shortwaves: Unhappy & Despondent”

From SWLing Post contributor, Troy Riedel:

I’d like to thank the SWLing Post Nation for their input re: my EMI/RFI issue (see: this previous post). It’s been a long 4-months and I’d like to share the results and outcome of my situation.

I will pick up where the last post ended and if anyone needs a review of the situation you can re-read the link to the original post in the previous paragraph.

At my expense, I hired an independent Master Electrician outside of the pool contractor. He and I reviewed everyone’s suggestions (I hope I’ve remembered to capture them all below but if not, rest assured it was fully explored and investigated). I have copied reader comments exactly as they left them back in October: Continue reading →

Guest Post: Peter’s FM CB Update

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Many thanks to SWLing Post contributor, Peter Laws, who shares the following guest post:

Thomas – Still Famous

by Peter Laws

We’re getting closer to the first legal FM CB on the market in the USA. President Electronics USA has announced that the President Thomas FCC CB radio will hit dealers in early 2022.

When first reporting on this, the assumption was that the Thomas FCC was going to be an FCC-spec Thomas ASC, a somewhat long in the tooth European multi-norm set. As the release date has approached, and President has released marketing collateral, it’s apparent that this new product is, in fact, a rebranded President Barry II, a current-production state-of-the-CB-art AM/FM European multi-norm model.

Richard, G0OJF, a pipe organ restoration and two-way radio expert from Lincolnshire, England, runs a wonderful YouTube channel “UK FM CB radio servicing”, where he restores old UK-spec CBs and then tests them on air. He also tunes up newly-released UK-spec CBs … and occasionally demonstrates restoration of 150-year-old pipe organs. He recently covered the Barry II so if you are curious about the Thomas FCC you are strongly encouraged to watch his video about its European counterpart.

Your humble reporter, who, perhaps surprisingly, has not followed the CB radio market since, (checks notes), 1977 or so, was amazed to see that the MSRP will be $109. In 1976 terms, that’s just under 25 bucks and had CBs been that price then, your reporter would have bought three because he’d been saving his pennies and that was the amount he’d saved!

Undoubtedly, the reduction in cost is from using components that are readily assembled by robots. If you watch G0OJF’s video above, you’ll note that the unit is almost completely made of surface-mount components. Remarkable.

Watch for dealers to begin offering these in the next few weeks. Your reporter plans to buy one and will be hanging out on Channel 31 FM once it’s installed in his radio room. Presumably, President (and other vendors) will be watching to see how these units sell in order to make plans for releasing other CBs that include FM. An AM/FM/SSB CB would be quite versatile!

Let’s play a game: Spot the differences!

Full manuals for both versions are here:

President Thomas FCC operating manual

President Barry II operating manual

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Off the Shortwaves: Unhappy & Despondent

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Guest Post by Troy Riedel

Every radio enthusiast or ham operator knows this definition – something we all dread. Electromagnetic interference – also known as radio-frequency interference when in the radio frequency spectrum – is a disturbance generated by an external source that affects an electrical circuit by electromagnetic induction, electrostatic coupling, or conduction (Source: Wikipedia).

I’ve been “off the shortwaves” (in fact, off ALL bands!) for a few weeks (a reminder to those who do not remember – I’m an SWL’er, I’m not a ham operator so I’m a listener only). Here’s my story:

My house was built in 2004 thus the home’s electrical is “modern era”. I’ve never, ever had a significant problem with RFI … except when the dishwasher is running (if it’s running, I have ZERO reception).

I didn’t want this (I acquiesced only in an attempt to become grandfather of the year), but an in-ground (vinyl liner) pool has been installed in my backyard (yeah, I’ve probably lost everyone’s sympathy with this statement). If it’s any consolation, construction started long before the summer and won’t be fully completed until [hopefully] next Spring (and what’s left of my yard is a disaster zone and something that will cost a fortune to mitigate – maybe I’ve gained back just a little bit of sympathy?).

Pools are required to be bonded (the process by which the electrical and metallic components of the pool are joined together with a wire to form a non-resistive path between the components. The goal of bonding is to connect, contain and prevent the transmission of any harmful electrical voltage to pool equipment, people and pets).

I’m not an electrician, but essentially the pool is grounded by a copper wire … and a copper wire “ring” encircles the pool (now covered by the concrete pool deck). The copper wire runs underground and resurfaces where the pump & filter are installed. That copper bonding/grounding connects to the remote master switch at the pump & filter (pictured here – note where the copper line connects to and grounds the unit):

Electrical power line(s) run underground from the pump/filter area until resurfacing just outside the garage wall where they enter my home’s main breaker box inside the garage.

There is an unfinished electrical component. A conduit was installed to add a pool light when the project is completed next Spring (see below), but at this point there’s nothing connected thus a “pool light” is not yet present.

Throughout the dig, installation of the steel walls, pouring the concrete bottom & steps, liner installation, the bonding, and covering the bonding “ring” with the concrete pool deck – all of this had zero negative effects on my SWLing.

Once the pool electrician connected power (connected the pump/filter) to the house, ALL radio bands were knocked out due to very extreme RFI. All bands – the complete spectrum (choose your letters … AM/MW, FM, SW, VHF, UHF – all bands).

I’ve easily spent double-digit hours trying to isolate the EMI. This is what I’ve done & discovered:

(1) Disconnected the pool grounding: no effect.

(2) [Only] Powered-off the two main breakers for the pool pump & filter: no effect (the pool equipment was tested, then the pool was winterized so nothing has been running).

(3) We used a handheld EMI detector over every inch of the interior and exterior of the house. Yes, there are sources but nothing to the level that should cause a radio blackout.

(4) Turned off the main breaker, all power to the house: this is the only thing that eliminated the EMI/RFI.

(5) Multiple times, I’ve painstakingly turned-on one breaker at a time (isolating each circuit, on/off then proceeding to the next breaker). I’ve found that for whatever reason, extreme RFI returns (and is present) on these three circuits: (upstairs) Master Bedroom (my Listening Post), the other upstairs bedrooms (combined on another circuit), and the (downstairs) Family Room circuit. Note: Even if everything is unplugged on one of these circuits, just turning on the breaker introduces the extreme RFI (thus it must be coming from the breaker & not introduced from a device plugged-in). Ferrite chokes have been installed on nearly everything plugged-in to outlets on the three “trouble” circuits. I’m not saying the house was an RFI-free zone before the pool – but these three circuits only produced light-to-manageable RFI prior to the pool equipment being connected to the house’s main breaker box. After 6000+ days of living in this house with no significant RFI issues, I’ve been in a complete radio blackout with very extreme RFI since the moment the live electrical line was connected between my pool pump/filter and my main breaker box.

And before you ask: No, there have not been any new electronics, no new devices, no new appliances, no LED lights, and all big screen TVs and other notorious RFI unfriendly devices are unplugged – nothing new has been plugged-in or added to the household except for the pool equipment. There have been no new utilities in my area that could have caused a coincidental problem (no DSL, no fiber optic – nothing). I cannot see how this situ could be caused by a neighbor, because the problem ceases when my power is off. And “no”, I can’t move my Listening Post because even though the majority of the RFI is introduced over those three circuits, the entire house is impacted and it’s a complete radio blackout.

To reiterate, I had no radio-related problems during the entire construction (I listened to my radios as I pleased) and the problem did not start until the pool’s electrical line was connected to the main breaker.

Could the new wiring – at/inside the breaker box – be improperly shielded? Could something be touching(?) that shouldn’t be? Could something be loose inside the breaker box? The three circuit breakers that are introducing the extreme RFI are in close proximity to each other in the breaker box and in close proximity to the two new pool breakers – could there be contamination from one to another?

I don’t make it a habit to play with electricity. The pool company could frankly care less about my radio woes (it’s my problem, not theirs). My power company supposedly checked their utility line coming into my house (I didn’t see them here, but they said the problem is not on their end). And local electricians all essentially say, “[from their prospective] EMI sources are hard – if not impossible – to find”.

I have an electrician lined-up but we both thought it might be best to “put this out there” because someone may have an idea that he hasn’t thought of. Thus far, I’ve done almost everything myself that they stated they would do (minus opening-up the breaker box). I’m hoping to solicit ideas from the SWLing Post Nation before I put the electrician on the clock. And on the clock = $$$.

Thanks in advance for your input. If I can’t get this mitigated, a liquidation event may be in my future.

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Guest Post: Peter discovers the first FM-capable CB radio for the US market

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Many thanks to SWLing Post contributor, Peter Laws, who shares the following guest post:

Thomas is Famous!

by Peter Laws

A few weeks ago, a summary of the recent change to Title 47 of the Code of Federal Regulations, Part 95, Subpart D — better known as the rules for the CB Radio Service — was published here. That change, following a successful petition for reconsideration of a previous petition allowed FM as an additional mode in the CB Radio Service. The original petition was the one that caused the FCC to do away with the nearly-impossible-to-enforce “DX Rule” that prohibited communications of more than 250 km. For one, the ionosphere had a long history of ignoring the rule entirely, at least for part of the Sun’s eleven-year cycle.

In that article, the author speculated that it may not be too long before manufacturers brought radios that were capable of FM to market, since they already existed in other markets, namely countries that were members of CEPT.

That author has been watching the FCC OET site to see who will be the first out of the gate to get an FM CB approved. The Office of Engineering and Technology is the FCC’s line office that handles, among other things, Equipment Authorization. They also handle Experimental Licensing, i.e., “Part 5”, like the recent 630- and 2200-m band projects that resulted in new Amateur Radio allocations and the ongoing 8-m band experiments under WL2XUP (see that license’s details at https://apps.fcc.gov/oetcf/els/reports/CallsignSearch.cfm).

OET also provides a public database of equipment authorizations. If you know a radio device’s “FCC ID” (usually an alpha-numeric string found on the label of a device or in the device’s documentation), you can look up the details in the database. A manufacturer’s ID — the first 3 to 5 characters of a product’s ID — will show all the devices that have been authorized. Fortunately, you can limit the search by date as by frequency range. https://apps.fcc.gov/oetcf/eas/reports/GenericSearch.cfm Authorizations available online go back into the 1990s but the further back the results go, the less detailed they become.

So who won the race to bring the first FM-capable CB radio to the US market or at least to get a product authorized? Our benefactor, Mr Witherspoon, will be thrilled to hear that the first radio to gain FCC authorization is the President Thomas FCC!

The President Thomas ASC model in Europe.

As soon as President Electronics can get stock to distributors, the radio should be available. This writer has no information about when that may happen.

The President Thomas FCC is an older design (c.2013), meaning that whatever R&D costs President Electronics had for the bulk of the design will have been amortized years ago. As noted in the previous article, changes for conformity with the FCC Part 95 rules are expected to be minimal and likely have to do with locking out the “multi-norm” ability in the new model’s European counterpart. Following FCC rules, this is an AM radio that has FM as well. The new Part 95 regulations require AM in every radio with FM as a possible option.

Several websites have details on the existing President Thomas ASC (ASC is automatic squelch control). [See photos above.] It’s a multi-norm radio as is common in the European market and offers CEPT channels, UK channels, and Polish channels among others. CEPT channels are identical to the FCC allocations, UK channels are completely different though still between 27 and 28 MHz, and Polish channels are exactly like the FCC channels except that they are all 5 kHz lower (i.e., our Channel 19 is 27.185 while their Channel 19 is 27.180). Here is an example of a site with data on the European version: http://www.cbradio.nl/president/thomas.htm

FCC authorization was long ago turned over to contract labs. Here is the Equipment Authorization for the President Thomas FCC:

https://apps.fcc.gov/oetcf/tcb/reports/Tcb731GrantForm.cfm?mode=COPY&RequestTimeout=500&tcb_code=&application_id=AgTi5CpzImyrjI5Oicfj2A%3D%3D&fcc_id=2AEOCPC208

Peter Laws

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Keepa extension & Eton Bundle

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Guest Post by Troy Riedel

Click to enlarge the photo

I decided to compose a post that ‘kills two birds with one stone’.

Almost every time a post appears here that states something like “Amazon its selling WXYZ Shortwave Portable for the lowest price I’ve ever seen”, I typically post a comment “doesn’t everyone use Keepa”?

Okay, lets kill the two birds:

Bird #1: Amazon (3rd party seller fulfilled by Amazon) started bundling the Eton Elite Field BT Radio, a carry satchel & the Eton Elite Mini 30-days ago (how do I know, I’ll explain that below with bird #2). The bundle was introduced at a price of $179.95. Frankly, given the street prices of the Elite Field with satchel & the under $25 street price of the Elite Mini, $179.95 wasn’t a great price. But at the time I start writing this post, 3-hours ago the price dropped to $139.00. That’s a pretty good price IF you’re looking to buy all 3 in this bundle (or even if you want the Field with satchel but choose to gift the Mini as a Christmas gift).

But this opportunity brings me to:

Bird #2: Keepa.

Click to enlarge the photo

Keepa is a great extension (pictured above loaded on my Safari browser). I have Keepa loaded into multiple browser applications. With Keepa loaded, I have a complete history of Amazon pricing. All-time Amazon pricing! Take a close look at the graphic (click to enlarge).

Keepa tells me this item has been listed on Amazon for 30-days. It tells me the starting price was $179.95. It gives me a day-by-day graph of the Amazon price. It shows me that the price dropped to $149.00 on October 26th at 16:56 EDT. And it tells me that, 3-hours ago, the price dropped to $139.00.

Want the average Amazon price over the last 90-days? Easy. What about the average Amazon price for the past 180-days? Easy – I get that, too (note: this item has only been listed for 30-days, so the 90-day & 180-day average pricing is the same).

Some of what I am telling you – re: the exact time of the price drop – is only visible when you’re [live] on the product page and you move your cursor over the graph (that info pops into view).

And here’s the best part: you can Manage Price Watches. What does that mean? I can set a target price and Keepa notifies me if/when the product’s price meets or goes below my target price (what I want to pay for it). I cannot tell you how many times I have had items with price watches set … and a few days … or a few weeks go by and <Ding>, I get an email notification that tells me my desired item has dropped below my target price. I set price watches for radios, tools, tents – even my contact lens solution! I Manage Price Watches for anything that can wait days, or weeks or even months to buy (I let the price dictate when I buy the item). Keepa even gives you 24-hours advance notice of an Amazon Lightning Deal.

In summary, this bundle is a pretty good deal as it includes two SW portables & a carrying satchel for the Field. But this also gave me an opportunity to show everyone how I use Keepa. I use Keepa for every item I view on Amazon. And if you look closely, there is an eBay link in Keepa … with a click of my mouse/track pad, I can compare eBay pricing to Amazon. If this item had ever been listed as “Used”, I could graphically track used pricing. Keepa also tracks Warehouse Deals & even the date, time & price of past Lightning Deals. Why would anyone not use this handy little extension? It’s like tracking a stock’s price history except I’m tracking a specific product’s price on Amazon.

But then again, if everyone did use Keepa … there’d be no point in readers sending Amazon deals to Thomas!

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