wythall radio club

Wythall RC portable operators were bathed in the spring sunshine!

Meanwhile Ian M0LQY was using a QRPLabs QDX 5w digital transceiver and a SOTABeams bandhopper antenna to make FT8 contacts over a wide area. 

• F5VMJ (Paul in Paris) – OP Winston 2E0EGP
• VU2GRM (Ram in Bangalore) – OP Neil G1TZC
• OE4EIE (Tom Bergenland) – OP Lee G0MTN
• ON7SX (Michel in Diepenbeek) – OP Lee G0MTN
• DL8SDQ (Juergen in Nordheim) – OP Neil G1TZC

Simon G4TVR was a surprise winner in Wythall Radio Club’s Easter Contest 2025!

He topped the 2m/70cm FM section and Lee G0MTN won the all band/all modes category.

This year members made much greater use of different modes and bands. 

There were contacts on 40m, 12m, 10m, 2m and 70cm bands. 

Members made use of FM, SSB, CW, FT8, D Star, Echolink and SSTV (slow scan TV – using the Club’s MB7WL SSTV repeater). 

They also accessed the GB3WL and GB3XO repeaters (with thanks to the GB3XO team in Redditch). 

Mobile contacts were also recorded. 

And Lee G0MTN operated remote into his home station via his mobile phone while on a shopping trip.

That’s dedication!

There was even an AM (amplitude modulation) contact between Winston 2E0EGP and John M6KET!  Now, that’s real old-time radio!

Wythall RC runs club contests during the Christmas and Easter holidays. 

Members try to contact each-other, with a point awarded for each contact and a multiplier for each member worked.  

The final score for each member is calculated from their best 3 days.

COMING UP AT WYTHALL RADIO CLUB……

Tuesday 20th May 7.30 onwards

Portable radio activity on the lawn at Wythall House, and chatting in the bar later on.

Visitors welcome

Tuesday 27th May 8pm –

Lee G0MTN will be talking about the forthcoming World Radiosport Team Championship. 

In the Darts Room, Wythall House.

Visitors are welcome.

When you buy an auction lot of morse keys based on some remote auctioneer’s pictures and description, you can never be sure what you are going to find in your parcel when it eventually arrives.

Will the items be complete? Will they need extensive restoration or repair?  Would it contain a rare collector’s item?

When I took the Morse Equipment Ltd Key from its packaging, I was attracted to the gracefulness of its design, its unusual spring tensioning and contact adjustment. It was in very good condition and didn’t need any restoration apart from a clean but it certainly warranted some research as to it history.

This model 605 landline key was originally known as Great Northern Telegraph Works, Copenhagen-Denmark Key and was made in the period ~1948 to 1969. However, it turns out that the key I purchased at the auction, is a British copy, made under licence by Morse Equipment Ltd, of Tring, Hertfordshire in the UK and marketed by Sedgewall Communications Group in the 1960/70’s.

I haven’t been able to exactly find out the nature of the relationship between GNTC and Morse Equipment Ltd. Both the British and Danish versions have the same pattern numbers in the Bakelite moulding.

Figure 2 Label on GNT key

Figure 3 Label on Morse Equipment version

Looking at the base of this key I could see what looks  to be spade terminals that are designed to mate with a fixed base of some kind.

From a Google search on PA3EGH’s website, I can see that GNT keys were also supplied with a Morse Inker machine 1515 which was used by the Royal Dutch Navy and other Signal Schools to check the quality of the Morse code that was transmitted by the operator. 

The key clearly plugs straight into the base of the Morse Inker (See Figure 4).

Figure 4 Morse inker machine 1515 with adjacent Key

Figure 5 Under view of Key showing spade terminals

Three things stood out to when researching this key, which I thought, warranted further investigation.

1. Who or what was The Great Northern Telegraph Company (GNTC) and why was this design of key attributed to them?
2. Who were the Morse Equipment company of Tring UK and how did they get involved with GNTC? What other morse products did they make?
3. The unusual, and possibly unique, spring tensioning arrangement on the key and its method of contact adjustment.

Figure 7 showing interface board fitted

Figure 6: underside of key showing matching interface board

The Great Northern Telegraph Company (GNTC)

The origins of this company, go back to the mid-nineteenth century, where the development of the telegraphy method of sending messages in morse code, initially along railway lines, became well established and the prospect of sending telegraphic messages between countries and even continents via submarine cables became a real possibility.

The first transatlantic telegraph cable became operational on 16^th August 1858, between Valentia Island of the west coast of Ireland to Trinity Bay, Newfoundland but the signal quality declined rapidly slowing transmission to an almost unusable speed. Sadly, due to an excess of applied voltage to try and improve the quality of the signal, the cable was destroyed after only 3 weeks.

A second cable was laid in 1865 with improved materials but when only half-way across it broke and was never found so repair was abandoned, A third cable was laid in 1866, luckily, they were also able to retrieve and repair the second cable so eventually there were two cables across the Atlantic.

One cannot under-estimate the impact that telegraphic communications had on the world in the nineteenth century. The ability to send and receive messages around the world in minutes rather than weeks was to have a profound effect on the commercial, political and financial life of the whole world and the race to cable up the planet was well under way by the close of the nineteenth century.

In 1868 a Dane, C.F. Tietgen, set up three small telegraph companies to connect Scandinavia, England and Russia telegraphically via submarine cables, which he did over the next three years;

1. Danish-Norwegian-English Telegraph Company to lay a cable between England and Denmark and between Denmark and Norway.
2. The Danish-Russian Telegraph Company to lay a cable between Denmark and Russia.
3. The Norwegian- English Telegraph Company to lay a cable between England and Norway.

Shortly afterwards Tietgen merged the three companies to form the Great Northern Telegraph Company, with its headquarters and main works in Copenhagen. Throughout the rest of the nineteenth century and the beginning of the twentieth century, the company continued to expand with cables being laid across Russia via Siberia to the Russian Pacific then onto Japan and China.  

The Company also started laying cables between Denmark and France and between England and Sweden and eventually between Sweden and Finland. Due to the expansion of international trade and shipping, the demand for telegraphic communications continued to grow rapidly and so the GNTC continued to expand. Figure 8 shows the 1907 route map.

Figure 8: GNTC Route map 1907

During the First World War 1914-18, the Company was able to continue its normal activities and although some cables were damaged, repairs had to be deferred owing to the presence of mines and wartime conditions in general.

Improvements in cable technology meant that the volume of traffic was able to increase despite these war-time interruptions. The GNTC was just one of many hundreds of cable companies around the world that existed to satisfy the never-ending demand for telecommunications. Some of these were to become state-owned, some remained private corporations. Some still exist and some have disappeared completely and some are known by other names.

After the First World War, all were to feel the competition from the development of radio communication circuits as an alternative to submarine cables. The Company went on to develop radio circuits in addition to their cable routes but the competition from the predominantly state-owned radio routes gradually became tough for all cable companies.  

At the same time as the rapidly increasing number of international radio circuits was limiting the volume of traffic on the Company’s submarine cables, the economics of their cables was further weakened by the decline in telegraph charge rates and by rising operating costs.

However, the Company sought to reduce the effects of these by continuous technical improvements in cable design and the development of faster transmission modes such as Telex/Teleprinter. They gave new life to the submarine cables and the use of hand sent morse started to decline.

Fortunately, during the 1930’s and 1940’s the Company developed a strategy of investing in various companies across the various industrial sectors, including batteries; radio telephones (Storno); telephones (Telematic); measuring instruments (Elmi) and hearing aids (Danavox).

In 1985, The Great Northern Telegraph Company changed its name to GN Store Nord with the aim of creating a new group identity and organising its businesses. In this process, all subsidiaries were re-named to include GN: GN Danavox, GN NetTest, GN Automatic, etc.

A major change happened in 1991 when GN was assigned the attractive GMS concession from the national Danish telecommunication authorities. In March 1992, GN’s new subsidiary Sonofon opened the first private mobile telephone network in Denmark. With the blossoming of the data communications and telephony industry, GN was back on track and enjoyed big success in the late 1990s.

In 2000, the company sold Sonofon to the Norwegian telecom operator Telenor. However, it was also about this time that the world-wide boom in telecoms companies suddenly became a bust. Many major telecommunications companies were forced to sell off subsidiaries, to avoid bankruptcy.

GN Store Nord’s headquarters are currently in Ballerup, North of Copenhagen, Denmark, focusing on its two core businesses; hearing aids and headsets, where it has demonstrated continued success in developing new technologies.

The Morse Key

I have not been able to conclusively establish who this key was designed by. I have to assume that GNTC themselves designed the key and originally manufactured it in its Copenhagen Works.  

Given that GNTC established themselves as manufacturers and designers of numerous telecommunication and audio products, this would seem plausible. However, I have also seen it referenced as the Danish Ericsson Style Long Lever Key on some websites. But how did it come to be manufactured by Morse Equipment Ltd and marketed by Sedgewell  Communications? What was the relationship between these three parties?

I found an advert for Morse Equipment Limited of Tring in a 1973 issue of The Wireless World, which I have reproduced below. During and after the Second World War, there was a huge demand for telegraphy equipment such as teleprinters, telex machines, inkers, undulators, perforators, tape transmitters and morse keys and the advert  clearly demonstrates this. (See Figure 9)

Figure 9 Morse equipment Ltd Advert from Wireless World 1973

The morse key itself is quite stylish, being housed in a fully enclosing Bakelite cover.  These keys would have been used to key valve transmitters so hence the need for the safety cover to avoid touching the terminals, where there might be 50-60V at a few mA.

It has no weight to it so would have to be screwed to something substantial to avoid drifting around the operating table. This why it was designed to mate with something else via the spade terminals and fibre board arrangement. Like many morse keys from Scandinavia it has a long lever arm.

The contact points are easily adjustable from a slotted screw accessed from the top. Contact is made when the lever is pressed, and the lever arm contact rises to connect to its mating contact. The gap is easily visible through the housing so setting the gap using a feeler gauge is possible. (see Figure 10).

Figure 10 Contact access

Unlike most straight keys the lever arm tension spring is mounted horizontally rather than vertically and is connected to a spigot which forms part of the lever arm pivot arrangement. The spring tension is adjusted via a knurled knob which sits just under the lever arm. (see Figure 11)

Figure 11 Spring Tensioning

I connected the key to my morse oscillator to get a feel for how it would be to use. It was ok. I could probably spend some time in getting the contact gap and spring tension more to my liking but to do that requires some time on a long QSO.

For that I need to find a suitable heavy base to give it some steadiness. I probably won’t do that, but either keep it in the collection or pass it on to another collector. I doubt it will take the place of my Marconi NATO key as my preferred straight key for operating.

Chris G0EYO

April 2025

References:

I used a great many resources to research this article. I am unable to identify individual sources but the following were very helpful;

https://atlantic-cable.com/CableCos/GreatNorthern/index.htm

https://www.tronico.fi/OH6NT/keys.htm

http://w1tp.com/imwyn.htm

http://w1tp.com/iperkcol.htm

https://www.webx.dk/oz2cpu/key6.htm

https://www.pa3egh.nl/morse-keys-from-europe/morse-keys-denmark/

https://www.facebook.com/groups/1232401453542260/ (CW Bugs, Keys & Paddles)

It’s always fun to receive a recording of one’s signals. 

Even better is to receive a video!

So I was delighted to have an e-mail from Dimitris (aka Jim) SV8ANW with a video of our recent 10 minute CW QSO on 30m.

Click here to see the video of our QSO

I could tell that Jim was using a bug key as they have a distinctive sound. 

Having owned a Vibroplex in the past, I was intrigued to see him clip a clothes peg on to the vibrating ‘dots’ arm during our qso. 

He tells me that this increases the weight on the arm, so slowing the oscillations that produce the dots.

You can hear that the timing of the dots relative to the dashes is better once the clothes peg is used.

That’s high tech CW!

I wish I’d known of this trick when I had my Vibroplex bug, as I always found my dots being produced faster than they should have been – despite following lots of advice on how to set up the key.

Restoring the RAF/Air Ministry Type D Morse Key ref:10F/7373

Figure 1: RAF Type D Morse Key as purchased

I bought this key, along with two others of the same type, from an Auction House in Newcastle in 2024. This one was in the best condition and complete, the other two had no interconnecting leads and one of those was missing the bakelite cover.

The Type D key was made by The Marconi Company and was a big ground station key with heavy duty replaceable contacts for use with high power RAF/Air Ministry transmitters both land based and those at sea. Because they were often used keying high voltages, the key is fully enclosed to protect the operator.  Early versions have “ MARCONI’S WIRELESS TELEGRAPH Co Ltd. No xxxx LONDON inscribed on the base, later ones have unmarked bases. This example has an unmarked base and dates possibly from the 1970’s.  (fig:1)

The key is made of brass and has adjustable contact spacing and spring tension. It is a precision design with zero side play. The 11m thick ebonite base has two through holes for hold-down screws and a hole for a threaded brass bush with knob for securing the bakelite cover. There are two holes for the cover locating pegs and the key has brass clamps for securing up to 8 cables. The key measures 101 x 90 x 183mm and weights about 1kg. The ref 10F/7373 is a UK Air Ministry Stores  reference identity, originating from 1918 and in 1952 was replaced by the NATO Stock referencing system, for the Armed Services, which is a 13 digit NATO Stock Number (NSN) consisting of a 4 digit classification code (NSC) and a 9 digit National Item Identification Number (NIN). The first 2 digits of the NIN identify the country of origin (99 for UK).

         Figure 2: Key with cover removed

When starting a restoration, I always several photographs of the unit, with and without cover. (fig 2).

As I disassemble the key, I put groups of parts in small plastic bags which I then mark up with a number and short description. I annotate a picture where the part goes with the same number. By using this numbering system on disassembly; 1,2,3,….8 etc, I then know the order in which I need to assemble the parts when building the key back up.

This particular key was rather dirty and it was hard to tell that it was made of brass. To clean  brass I use a metal polish with very fine steel wool, then clean off with cotton wool pads and give it a buff up with a “Dremel” fine brush.  Some people would rather leave the “kay’s patina” as it is rather than “clean and polish it”. I respect this view, but I enjoy the knowledge gained from the disassembly and re-build because it forms more of an attachment with the key. Everyone to his own, I guess.

The disassembly was relatively straight forward. The ebonite base has a glass fibre board screwed in place which gave access to the key fixings when removed. The cover, base and key knob were washed in soapy water. There is a mark on the cover where the impressed key identity label is, that I couldn’t remove without resorting to stronger chemicals and I feared irretrievable damage if I experimented with it so I left it as is. I cleaned the brass parts as best I could and gave a light rub on the silver contacts with very fine steel wool.  Some of the fixing screws and washers are steel and are showing signs of corrosion, I cleaned those up as best I could but decided not to replace them.

 In common with armed service morse keys, there is the facility for connecting a SPACE contact which is normally closed when the key is at rest. (figure 6)

 figure 6: SPACE contact at front of key

This was not wired into the jack plug fitted, which looks original and still has the On Her Majesty’s Service Label attached. It cleaned up rather well and I felt it was worth the effort. I don’t know whether to keep this key. It was the best of three identical keys that I purchased and one of those doesn’t have a cover so that one should be sold on at least. Compared to my Marconi Nato key I find that it feels less comfortable to use in long QSOs and I already have a nice Kent brass key that was my favourite SK before the Nato key along. I think if I was to sell the RAF Type D key I have just restored I could get around £90+ for it on EBay. Ones with damaged covers seem to regularly reach £70. ( I have signed up for MKA (Morse Keys Anonymous).

“ Hello my name is Chris and I am addicted to buying morse keys!”.

73

Chris G0EYO

Restored RAF Type Morse D key

Key after clean up and restoration

  Key after restoration : top       view

COMING SOON:

TUESDAY 1ST APRIL : OPEN COMMITTEE MEETING -8.00

THURSDAY 17TH APRIL-MONDAY 21ST APRIL: THE GREAT WYTHALL RADIO CLUB EASTER CONTEST

FRIDAY 18TH APRIL: FRIDAY MORNING CLUB 9.45-11.45 (OR POSSIBLY EXTENDED FOR WORLD AMATEUR RADIO DAY?)

RadCom ‘Club News’ for April reported on Wythall Radio Club.

Here’s an edited version…..

It’s been a busy Spring at Wythall Radio Club.

Our annual Christmas Contest attracted keen competition between members.  Lee G0MTN, our contest supremo, announced the results to an expectant meeting in mid-January, with the top scorers only separated by a few points. 

David G7IBO won the 2/70cm FM section, and Mike G4VPD found a couple of extra multipliers to gain first place in the all-bands/all-modes section. 

The 6-day competition involves Club members contacting eachother on various bands and modes, with bonus points and multipliers leading to keen competition – although there is always time to chat!  We are delighted to report increased activity from members compared with previous years.

Lee GoMTN made remote QSOs from Poland, Munich, and the centre of Birmingham, using his mobile phone to access his home rig.  There was much greater use of CW, with 5 members active most days. 

Some QSOs were on 12 meters, where ground wave propagation enabled contact between members 10-15 miles apart.  Good use was made of the Club 145.225MHz frequency and GB3WL repeater.

Our new members are making a very positive impact in the Club.  Martin, who joined the Club in 2023 as an SWL, has made rapid progress through the exams with the help of tutoring by our training coordinator Chris G0EYO and the Bath scheme, and now has his full licence – M0XFI. 

Like several other members, he participated in the Club’s ‘How low can you go?’ QRP month in January. 

Impressive results were achieved using a maximum of 5 watts on CW and 10 watts on SSB/digital, including working north and south America and Asia.

In our ‘miles per watt’ challenge, the top scorers were John 2E0XET with a stupendous 3543 miles/watt for his 1-watt CW qso with Virginia USA and Lee G0MTN’s 713 miles/watt from his 10-watt digital contact with Argentina.

The Club has a growing group of CW operators, many of whom used this mode to work other members during the Christmas Contest.  Clive M0KNP, having recently achieved his full licence, is  participating in the CWOps training programme (and just completed the first module – well done, Clive!) and made his first QSOs on the key, as has Neil G1TZC. 

And not just CW operating!  Chris G0EYO has continued the restoration of his historic Morse code key collection…. as you can read here.

In February, a large gathering of members welcomed Jamie M0SDV, to talk about the 8R7X dxpedition to Guyana that he co-led in 2024. 

Jamie obtained his Foundation licence through our training scheme and is now a highly experienced contest and dxpedition operator and leading advocate for younger amateurs.  His talk provided an amusing and insightful look at this very successful operation.

Our re-established Friday-in-the-Shack, held monthly, has a good attendance.  The focus is ‘bring and show’ hands-on activity and technical discussion. 

Recent sessions have covered John G3VRF’s modular QC100 rig and Phil 2E0WTH’s mag loop.

Amateur television is an interest of Derek G1INC and Neil G1TZC’s – both also new members – including home-brewing gear.  Thanks to their work, the Club has applied to host a SSTV repeater using the existing collinear on the chimney and spare 2-meter FM rig (this is now active, details here).

Club meets every Tuesday evening and visitors are always welcome here and at our special events, the programme for which is here and on our web site.

Wythall Radio Club is pleased to announce its new SSTV repeater is now live on-air.

Operating on 144.500MHz FM, this ‘store and forward’ repeater will give good coverage around the south Birmingham/north Worcestershire area.

Neil G1TZC and Derek G1INC have been working hard in the Club’s shack to get the repeater on air. 

It uses a 2 FM meter mobile rig (kindly donated by John G3OIC) running 5 watts to the Club’s collinear mounted above the GB3WL 70cms repeater array on Wythall House chimney. 

The system is controlled by a computer in the shack with remote management by repeater keeper Neil G1TZC.

A 1750 hz tone of 1 second is needed to open the repeater.  It will respond with a fast morse ident.

Then you have 5 seconds to start uploading your frame.

After the frame is received, the repeater will re-transmit it on the same frequency.

You can find Neil’s presentation about how to use the repeater here…..

Here are some images from the first days of the repeater’s operation…..

The Marconi Nato Morse Key
…..or to give its proper nomenclature 5805-99-541-1439 Key Telegraph. This is a
serious morse key, clearly for use in a military or service environment.

Unlike most morse keys which basically have two terminals that you connect via a jack plug to
your transmitter KEY socket, this beast has a 6 way terminal block under the cover
and an internal wiring loom. But before we get into the detail, why did I purchase this
particular key? Well it was on my list of “always wanted” keys together with the
Vibroplex semi auto bug; the Eddystone Semi-auto Bug; the Marconi Marine 365
straight key and a Kent straight key. I have promised myself that, apart from the
Marconi 365, the list has been satisfied, and it will have no further additions. There
were also historical connections of a past life working for the Marconi Company,
where we made the communications systems equipment for the Navy that these
morse keys worked with. 

Nato key with cover removed

This key was designed for use by NATO forces by Marconi S & R Systems and
made by Pryce Edwards Ltd in the 1970-80s and has the serial number PES 022 85
which would indicate a manufacture date of 1985. The key weighs 3 ½ ls (1.6kg) and
the cover measures 8” x 3.25” (203mm x 83mm) with an overall length including key
of 10.5” (268mm). My key has an ABS cover, others with slightly different NATO
numbers had covers made of brass or steel painted battleship grey.

The key is based on the Swedish Twin Contact design key c1940 by Lennart
Petersson, which is also known as the Swedish pump key; It uses a spring plate for
the support and spring tension on the main rocker/sending lever arm. There is a
spring tension adjuster, using a spanner and an allen key, that can only be accessed
by removing the cover.  The key has preset contact gap adjustments using a round
black knob on the top marked 0 -9. 0 being closed contacts; 9 being widest open.

Swedish Pump Key Spring action

I bought this key at an auction in Newcastle, so had no opportunity to examine
before bidding on it. It was with a collection of 5 other morse keys. Some few months later I took it off the shelf and decided to have a close examination of it. The first thing I noticed was that it had a ON/OFF switch which is unusual in a morse key.
Second, there did not seem to be any cable entry point, although there was a blank panel at the rear of the cover. Two thumb screws hold down the cover which slides off the base, revealing the key, the terminal block, contact adjustment knob, and ON/OFF switch. This was clearly a complex piece of equipment. Behind the terminal block there was a removable aluminium panel which could be removed and have a hole drilled for a cable gland. This made me think that the key had never been usedin service or modified for amateur use.

The Terminal Block can be seen at the rear of the key and it has the following label
markings;

6- C
5- S
4- LINE
3- MK (MARK)
2- SP (SPACE)
1- E (EARTH)

As this is a “two contact” key, I assumed that key lever was LINE and the UP contact
when key is pressed is MARK. When the key is at rest (down) this connects the LINE
to the SPACE contact. Trying to prove this with a continuity meter proved
problematical for reasons I will explain later. I could clearly see stand-off insulators
interfaced between the terminal block and the base of the key. Further investigation
led me to unscrew the base from the bottom place. This turned out to be some
hollowed out plastic material containing a pair of Capacitor – Resistor Key click
filters. (See below for a comment on Key Clicks). Faced with this and the continuity
problem, I decided to trace out the wiring diagram for the key, but I still couldn’t be
sure how the key click filter was wired into the circuit. Fortunately FISTS member Bill
G0ELZ sent me a circuit he had which confirmed everything. The circuit is shown  below.

C & R Key click Filter in base

I made some enquiries on the FISTS forum and Facebook about the key and was
told that the ON/OFF switch on the front of the key, is for switching the key out of
circuit of any transmitter, thus giving the operator control, and can prevent
accidental keying of the transmitter by knocking the key. Given that these keys would
be controlling transmitters located somewhere else on the ship or establishment this
seemed a reasonable explanation. Dave M0VBY another FISTS member said that
the S and C on the terminal strip probably stood for Screen and Common.

Dave’s first encounter with the Marconi NATO key was late 1972/73 when he served on
HMS Bristol taking the new Integrated Communication System 2 (ICS2) to sea for
sea trials and later as a fully operational capability. (Dave was a maintainer, not an
operator).

Dave said he had no evidence that this key was used anywhere other than the RN
and that the Nato stock number plate has given rise to the assumption that it was
Nato use. All naval equipment had a Nato stock number, replacing the old Admiralty Pattern no. The two digit 99 was the indicator that it was manufactured in the UK. In ICS2 the key was fitted in a comms bay on a sliding tray and could not be removed. It was connected by a Switch Unit Radio to the KMM control system, (Thanks for that
information Dave)

The continuity problem I referred to earlier concerned the MARK contact. When I
pressed the key lever the LINE contact on the lever should make with the MARK
contact and complete the circuit resulting in the key tone. There was nothing.
Eventually I realised that there must be corrosion on the key contacts so I removed
the screws holding the lever arm to get access to the contact points on the lever and
the key base.

Up/Down contact

The contacts proved easy to clean up with a light file and when I re-assembled the
lever arm back on the key I was able to get a tone when the key was pressed. The
contact spacing knob is very stiff to turn so that could also do with a check out.
Seeing how it is put together, its looks to be a very fiddly job so I will leave that for
later.

I haven’t restored this key yet. It only needs a good clean to remove marks and dust.
I also haven’t modified the rear cable entry plate behind the terminal block, I will
defer a decision on this until later. What I have tried to do in this article is to find out
how the key works and how it was used in operation. I have learnt a few things which
is never a bad thing. Until the next one!
Chris G0EYO 31/1/25

Key Clicks – a perpetual problem
Nothing can be more annoying (and a quick way to ruin your reputation) to your
fellow operators, when, unknowingly, you generate key clicks on your signal. Clicks
are generated by any transmitter whose RF carrier amplitude rises or falls too
rapidly, (which essentially is what a square wave CW signal is). They are heard as
clicking in time with the CW but audible on many frequencies right across the band
and are nothing to do with the operator keying speed. They arise because of the
rise-time of the carrier when the key is depressed. A very fast rise-time can be
thought of as a small part of a high frequency audio signal and it produces very wide
side bands. Conversely, a slower rise time equates to a lower frequency audio
signal. Key clicks can be reduced by a simple CR timing filter in the keying stage
which will round off the edges of the CW square wave. See Figs 7.3; and 7.4 below 1
Note 1: copied from the RSGB Intermediate Training Manual 2nd edition

No, it wasn’t the Flowerpot Men wot done it!

But my Flowerpot antenna – a ‘single’ band vertical dipole for 12 meters.  Those ‘inverted commas’ are significant – read on!

This is an antenna that’s cheap and easy to build (you just need to be able to strip some coax and solder on a PL259 or similar), and it’s hardly noticeable.  It can be hung from a pole, tree, window, etc.  It doesn’t have radials or a counterpoise.

I like experimenting with homemade antennas, and I wanted to take advantage of this sunspot maximum to work as much DX as possible on 24MHz.  My doublet works quite well, but perhaps a vertical would help by giving me greater low angle radiation?

The Flowerpot antenna is a centre fed vertical half-wave dipole made from coax. 

It comprises a quarterwave radiator made from the centre of a length of coax, below which is a quarterwave of complete coax that is then wound into an rf choke.  The tail of the coax beyond the choke forms the feeder.

The antenna radiates from the top quarterwave section of coax core, and from the outer braid of the bottom quarterwave section.  The choke prevents the outer braid from radiating further along the feeder.

There’s lots of material on-line about how to make one.  

It didn’t take long to measure up some RG58 and expose the inner core at one end.  I then marked a further quarterwave for the position of the choke, which I wound around some 40mm plastic pipe.

I used a dipole length calculator for my measurements.  As I usually do with my antennas, I cut it a bit longer than the calculated figure so I had room for adjustment.

I tied the top to my 8 meter Sotabeams telescopic mast, and pushed the mast up between the branches at the bottom of my garden.  The radiating section cleared the fence on one side and the shed on the other.

The antenna analyser showed there was a dip at about 24.9MHz and an swr of 1.7:1, easily resolved by my rig’s ATU.  To my suprise, there was a bigger dip on 28.5MHz and an swr of 1.1:1 that covered the CW and SSB sections of that band.

So it looked like the antenna wasn’t too long, but too short!  Perhaps this was caused by the close proximity of tree branches?

Two bands for the price of one!

My K3 has dual antenna sockets, so switching between the Flowerpot and doublet on receive, I immediately noticed signals were affected by up to +/- 2-3 s-points on both bands.  Presumably signals ariving by different paths.  There was not much difference in the noise floor.

Now I can alternate between antennas when I put out a CQ call, and also choose the antenna with the strongest receive signal when I call someone.