TELEGRAPH KEY

I've always had a keen interest in the mechanics of speed keys and how they evolved.  I only collected speed keys to learn about their mechanics.   What follows is a summary of the many years of testing and learning about speed keys.   And what makes these speed demons tick.   During the testing process,  I came up with a  better way to slow down the dots on speed keys.    I call it the Extendadot.  Which is described in detail here and later in the journal.  

 

This summary of ideas for fine tuning your speed key is a work in progress.   I'll probably make updates to the procedure as time goes on.   I've fine tuned hundreds of speed keys and I can go through the process fairly quick.   But when I first started, it would take me days of frustration --- when I just couldn’t find the right combination of settings to produce good code. All keys are slightly different so it’s a matter of finding the keys "Sweet Spot"--- where code seems to roll off the finger pieces.    I hope this helps others to get the job done quickly --with a minimum of fussing around. 

If you found a speed key from the early nineteen hundreds, it was probably dirty and all beat up.   Most of the keys from that era eventually end up at estate sales.   After they have been stored in a musty basement for a half century, there can be rust and a heavy coating of dirt and grime.    The key parts can be removed and cleaned in an hour or two.  

Then all the parts on the key need to be lined up so that they are in perfect alignment and balance.  If you don’t have all the parts lined up perfectly, you will never be able to fine tune it for perfect code.     The key can’t be used until the rust and corrosion is removed from the straps on the bottom.   And the only way to do that is to remove the dot and dash contact posts as well as the contact posts for the keying wires.  Cleaning the corrosion off the screw heads and on the straps where the screw heads join up to the straps.   With the contact posts off the key, its then easier to clean the top painted surface with mineral oil using cotton balls and Q tips.   Mineral oil works really well to renew the paint surface without damaging it.       A lot of the older keys were stored near basement oil furnaces and you might need to loosen up the grim with rubbing alcohol in moderation. 

The nickel plating can be cleaned with some cotton balls and your choice of metal cleaner.   The nickel plating on the old keys comes off really easy, so you have to be careful to use only the slightest pressure.    The bakelite finger pieces can be difficult to remove without damage -- if the key has corrosion.   I’ve soaked them in mineral oil for a few days while still attached to the arm by placing the arm in plastic baggy with the mineral oil.   If you have one of the newer keys, the plastic finger pieces can break if you don’t first loosen the set screw before unscrewing the knob!!! 

The coil springs for the dot and dash arm can get compressed over the years.  It’s easy to uncoil them and put new life back in the spring by using a couple of small knife blades or other instrument to pull the coil apart.    This is especially true of the dot arm coil spring.  Most dot arm coil springs have a small loop on one end and a big hook on the other in order to attach it to the keys frame.   So take great care to not damage the dot arm spring.     If it should break, you can do what Les Logan did on his line of Speed X keys.   Just add a coil spring around the left side stop screw.  Take a look at the pictures of the Les Logan keys in this journal.   

After the key is cleaned and the piece parts attached back on the key, there are a few steps necessary to bring all the parts into perfect alignment.   If everything isn’t square and lined up perfectly, you will never be able to fine tune it for proper keying.  

 

The Dot contact post is fixed in position but you add or remove insulating washers under them.   The alignment of the dot contacts can be fined tuned by moving the pivot point up and down in the yoke as long as the end of the dot still contacts the damper at or below center.  I've found its best for the contact with the damper to be a little below center if possible.   

1. After the dot arm contacts are square and in perfect alignment, then the moveable dash contact can be centered in perfect alignment with the dash contact post. 
2. Most everyone wants a very light touch to the key.  But the only way the dot arm stores energy to the make the dots--  is with the dot coil spring tension.   So you need to have a pretty heavy spring tension in the dot arm coil spring or you wont be able to send error free dots.   If you have been using a paddle, it will take some time to get used to the extra spring tension needed for the mechanical dots.   Getting the dot arm spring tension correct is the most critical part of the process of fine tuning.   In this case, more is better up until the point where it causes fatigue.   Thats why you see so many of the commercial CW operators screwing the key to the desk. So it wont move around and you can slap it has hard as you want to make good code :-)  The Vibroplex keys from the early part of the century came with a hole already drilled in the base for a mounting bolt :-)
3. Set the dot arm right adjust screw so that the arm just barely makes contact with the damper. Its very critcal to have the dot arm just barely touching the damper while at idle.    Set the dot arm left adj screw so that the dot arm travels about 1/8 inch or so.   The official Vibroplex adj procedure calls for using an old analog type of VOM across the dot contacts.  Adjusting the dot contact spacing so that you have 50% deflection of the VOM.    And that does provide close to the correct weight to the dots.   When I first started fine tuning keys, I did it that way.    But now I just listen to the sound of the dots by keying the rig or code practiceset.   Depending on band conditions, there are benefits to having a very light weight sounding dot. When signals are weak and background noise is loud, it can be easier to pick out light -- well defined dots.
4. The quality of the dots depends on several factors. 
1. The main spring material makes a big difference in dots.  If the dot main spring is very stiff, then the dots produced will be very high speed -- even with several weights at the far end of the dot arm.   It’s the luck of the draw.  Some keys have weak main springs and some have very stiff main spring. If you’re lucky, your key will have a moderately stiff main spring and allow slow speed dots with just two weights.  Far too many keys were produced with main springs so stiff that the slowest dots were over 30wpm with two weights.  And that’s one reason why you hear so many hams sending such high speed dots with long dashes.  If the main spring isnt strong enough, then the dot arm can tend to  flop around on the damper and causes erorrs.  So the quality of the dot arm main spring is critical for good code.

 

1. After you get a good dot arm coil spring tension, --- the dot arm is just resting on the damper, ---you have about 1/8 “ or less spacing in the dot contacts.  Then listen to the dots produced and adjust the contact spacing till the dotshave the proper amount of make and break time for good sounding dots.  You might have to move the left dot arm stop screw in or out till you find the correct settings.  Then use an old analog VOM to have 50% deflection or listen to the dots on a code practice oscillator.  When I was first learning how to adjust speed keys, I would work for days and days and never find the correct settings for good dots.   And it was very frustrating.   The secret is having everything in perfect alignment and balance.  With all the parts square with the other parts.  And then a pretty heavy dot arm coil spring pressure.   After adjusting speed keys for many years, I can now adjust a key by just watching the parts and listening to the clicking of the dot contacts.  And it comes up really close to the correct amount of weight to the keying.  

The biggest problem with speed keys is:  the slowest speed of the dots using two weights is usually way too high.  And when you’re first learning the speed key, you need dots down to about 18wpm or lower.   If you add 3 or 4 weights to the dot arm, it can become unwieldy and that causes errors.  The best way to slow the dots down is to use a dot arm extender---  to place a small weight further out on the arm,  like in a pendulum.   One way is too use a  sliding extender -- that places the weight to the rear of the dot arm at slow speed.  At high speed, the entire length of the dot arm is the same diameter.  And that allows for higher quality -- high speed dots.    Its very slender and light weight and allows sending perfect code.    There are pictures and a full description of the Extendadot later in this journal. 

The final test of speed key performance is too compare the quality of the dots produced at the lowest and  highest speed.  If the key dosnt have any issues and its adjusted correctly, it will produce high quality dots at all speed ranges.   Try moving the finger pieces up an down and there should be no movement at the end of the dot arm. Wobble of the pivots or other issues with the dot arm cause the dot quality to change with speed.    There are a few keys you run across with such weak main springs that there is no way the key can make proper dots.   When the main spring isnt strong enough, the dot arm will flop around on the damper, and that causes dot errors.   I've seen some keys that someone had used a grinding wheel or file in an attempt to remove part of the main spring to slow it down.  In the end that sort of mod just causes it to flop around more on the damper. 

I’ve noticed the Vibroplex keys had consistently better main springs than most other keys.   Around 1940 Vibroplex started making deluxe speed keys with Jeweled Bearings.  If the Jeweled Bearings in the deluxe Vibroplex's are adjusted correctly, it can allow the key to be used with a lighter touch and that in turn usually produces better code.   What other keys have been sold with Jeweled Bearings?   Yep, there is none other than the Vibroplex Deluxe Jeweled Bearing! 

 

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This posting was just meant to be about speed keys. I seldom use a paddle on the ham bands.  I only included these paddles that I have owned for GP.  I'm sure there are many fine but expensive paddles available today.  Including the new single lever Schurr that just came out.   Here is the Schurr Profi and the V2L sitting side by side.  Both top of the line paddles.   W9WBL is very inventive with a lot of mechanical ingenuity.  As the paddles he produced were very unique with advanced mechanics.   Indicating he was a working at an entirely different level than most everyone else.  This particular V2L has Mastodon Ivory finger pieces.    The Profi key is lengendary for being the worlds best.  I was surprised at how well it did work.     I might have kept both of those paddles if they were non-iambic.    They both found new homes.     Same for the Bencher hand key and Bencher Iambic paddle.   The Bencher Iambic was one of the best paddles available when it first came out many years ago but today the design is dated and you dont have to look very far to do better.     I still own the March magnetic iambic paddle with ebony finger pieces.   The feel of the paddle using repelling magnetics makes it  easy to send with.  I'm not saying its the world best paddle but I enjoy using it and thats all that matters in your shack :-)    Its very easy to adjust the magnetic tension (very broad range), but the contact spacing and pivot bearings adj should have used fine threaded screws as they can be difficult to adj.  Its just fine if you dont change your contact spacing or pivots once its set correctly.   The only reason I have kept the March paddle is its built like an 1800's clock movement and  its very magnetic :-)   I dont care for Iambic keys and thats why the Vibrokeyer Gold Presentation Non Iambic is my favorite today.   I owned the Begali Simplex Iambic but I just didnt care for its ergonomics.  The K8RA paddle is very cost effective, there is no play in the very well engineered pivots and it has more tactile feedback than most other paddles.  The K8RA P2 Iambic paddle is a great value for the price.  http://www.k8ra.com/index_018.htm

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The Vibroplex Lightning was produced from 1927 through 1980.  There were different versions of it such as the less expensive Champion and various variations of it made by Bunnell and Lionel during WW2.  I've owned all of the Lightning style keys. Including the WW2 knock offs.   Something I noticed about the Lightning was the tendancy to have more critical adjustment range.  There was slightly narrow range of adjustment compared to the Original keys.  After I looked over the mechanical design -- trying to figure out why, I noticed the difference was the articulated dot contact assembly and the use of a dot arm coil spring that attached to a moving rod rather than directly to the keys dot arm--  as in the Original.  Also, the damper on the Original provides better damping with its articulated damping assembly.   The Lighting is capable of producing good code if adjusted correctly, but I think you will find the adjustments on the Original keys less critical.   The coil spring could be replaced by using a coil spring around the left side adjustment screw like shown on the Les Logan picture in this Journal.  That might help give a wider adj range for dots.  There were a lot of Champion keys sold to beginniners due to being so inexpensive.   When Bunnell made their version of the Lightning under license from Vibroplex during WW2, Bunnell improved on the design by using part of the features of the Lightning, and some features from the Original.  But it wasnt perfect since they used a tiny little damper wheel that isnt all that great.

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The roaring 20's were good years for the Vibroplex line of keys.  They had no competition since they had driven everyone else out of business or bought them out. During the 20's they produced some very good hand made keys.  Around 1920 Vibroplex switched to the Bent Lug design for the Pivot.  Up till then they had used the Pinned Double Pivot, where the dash and dot arm have separate pivots.  I consider the Pinned Double Pivot a superior design -- which allowed for more controlled sending.     Unfortunately, most all other key manufacturers copied the Bent Lug design.      The Model X  is a very ingenious design but when I first tried to send with one, I found it awkward.    After it had been the market for a number of years, they came out with an improved version of the Model X (around 1920) but it was soon discontinued. The model X uses a very long dot contact assembly that is extended all the way from the rear of the dot arm. Its sort of mechanically unwiedly.   I finally took some time to fine tune a 1916 Model X that was in like new condition. But first I fitted it with an Extendadot so it could be adjusted for dots below 32wpm.  It came equipped with such a light square weight, that its slowest speed was 32wpm. It was a long process of experimenting to find how the adjustments interact and what the key was capable of.   But after a few days of experimenting I managed to adj it so that it sends perfect code from 15 to 30wpm using slide on vertical weights. I managed to get the contact spacing down to about 1/32" for the dots and I was surprised at the high quality code it produces after  its set up correctly.   I had to tighten the main spring in its mounting--  as it had worked loose slightly.  And I also had to use an added screw to tighten the 2 1/2" long dot contact assembly.    Up till then the dots it produced were unacceptable.  I also had to use a different length screw to adj the dash stop travel so it provided less travel.  After I made those mechanical updates, its now a pleasure to send with.   After you get used to the feel of a properly adjusted Model X, it sort of grows on you.  I have it equipped with slide on vertical weights so that its not necessary to move  the square weight on the dot arm.   I can understand why the Model X  lost favor with telegraphers.  It has to be in perfect adjustment in order to produce good code and not everyone would have been inclinded to spend extra time with it since the Vibroplex Original is so much easier to keep in adjustment.    Your timing has to be more controlled when using the Mod X.  And thats why the code produced by the Mod X key has a more consistant dot to dash ratio.   Another way of describing it is, the Mod X is self correcting for poor operator habits.     

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Les Logan produced a large number of Speed X keys from his machine shop in San Francisco.  The keys that he produced were unique in that the dot arm coil spring was added around the outside of the left side adjustment screw.  If your Vibroplex needed a new dot arm coil spring you could use this method to attach any type of coil spring without having to modify the dot arm.  Over the years the adjustment screws on Les Logans can seize up in the cast iron T handle frame.  When they do seize up, its not easy to loosen them without marking up the screw heads.  Re-thread the cast iron and apply some anti-seize compound and it wont happen again.  All of the T handle bugs I've come across had adjustment screws seized up in the frame.  The thing I have noticed about the Les Logan/Johnson keys was the tendancy for the dot arm main spring to be a little on the weak side compared to Vibroplex.   I was lucky to find a Deluxe Chrome model that was new in the box.  Its the one with replaceable contact points and was found at a church rummage sale.   Exactly how it came about being new in the box is a mystery.  Les Logan and some others produced keys using 4 rubber feet.  If one foot was slightly different sized, the key would wobble.   Vibroplex  keys use 3 rubber feet and that means they are self correcting no matter the size of the feet. It would be extrodinarily rare to find a Vibroplex that wobbled on its feet :-)  Enclosed is also a picture of 3 Les Logan T handle keys at the operating position.   Each one adjusted for a different speed range with custom wood  finger pieces.  I used them in several CW contests with good success.   One of them came from the Telegraph Museum of Tom,  W1TP and its pictured on his CD rom of telegraph keys as key #7330.   Try this link to see the pictures of this key and other keys in his extensive collection on the web.     http://w1tp.com/m8000.htm

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I was shocked when I came across this 1943 Braniff Airways key in the original Vibroplex carry case.   I noticed the key had never been used.  And when I tried to fine tune it, I wasnt able to get a good keying line out of the key.  To my surprise, Vibroplex factory had installed the insulating material up side down under the  metal straps on the key bottom.   A few  minutes later I had it producing code for the first time.   So it had sat on a shelf somewhere.  Probably waiting to be repaired for many years.   Since it was manufactuered in the year I was born,  I've kept it on display in the shack but never used it on the air.   A very rare thing to find such an old key and it had never been used.  Although I did come across a brand new,  never used Les Logan Deluxe chrome key at a church rummage sale that was also new in the box, never used.  I'll post a picture of that gem later :-)   EF Johnson bought out Les Logan and his line of Speed X keys and after that they were made under the Johnson/Speed X name.  

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I've owned a number of Ted McElroy Deluxe speed keys.    There has always been a lot of hype around Ted's line of keys as "The worlds fastest Telegrapher".  The deluxe mac keys are beautiful with their marble painted base and "T" handle.   The "T" handle allowed the key to be picked up easily -- when the work shift was done for the day. 

I found the T handle Mac keys to be difficult to adjust and sort of crude.   The parts are large and it requires a very heavy hand to slap them around in order to send good code.  Also pictured is a like new Deluxe, with Ivory finger pieces and a leather carry case.  The Deluxe Mac keys had platinum contacts and a dot stablizer.  A picture of the dot stablizer is also included.  I also used to own the included picture of a P500 Mac key that is in like new condition.   The P500 was one of the last keys he produced before selling out to TAC.  The like new condition P500 in the picture has a very thick and heavy base of cast iron.   The last of the TAC bugs had a very large heavy base and all the ones I've tested sent dots way too fast even with both weights.  It would be best to slow them down by using a dot arm extender.  As just adding more weight causes the dot arm to become unwieldly -- heavy.   All the Mac keys are very collectable and a part of history.  But because they required such a heavy hand to slap them around,  I dont own a Mac key today.   You can do better :-)  But they do look good sitting at the operating position :-)   A very impressive hunk of steel :-)    Take a good look at the paint job on the P500.  Its the best paint job I've ever seen on any key.  Almost like velvet. 

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When I joined the Navy in 1962, I could already receive code at 40wpm.  So when I attended radio school, & graduated first in the class, I was allowed to pick any duty assignment in the world.   I picked Whidbey Island to be near home.  Big mistake.   I got Whidbey Island Naval Station but I was attached to a Seaplane Tender out of Whidbey Island.    I was soon to learn that Whidbey Island was home base for a large Naval Seaplane Squadron.   Then I was put on a plane for a 3 day trip to meet the ship in Okinawa. A six month deployment overseas.  Big surpise.   But the biggest surprise was yet to come a year later.   I spent that first six months overseas taking CW position reports from Seaplanes while they tracked submarines.   After six months of using a hand key, I had had enough of that already!!!   When we went back to the states for some R&R,  I bought an old Les Logan speed key.  Cut off the dot arm so there was some free space at the rear of the modified key for an electronic keyer.    I built a transistor multi-vibrator keyer taken from QST magazine -- onto the back of that Les Logan.  With a relay output so it could key the ships high voltage keying lines. The good part was the easy way to change the speed when required.    Then I took the Navy speed key test.   They didn’t make it easy to use a speed key and you had to provide your own key.  That next 6 months overseas was a piece of cake using the electronic keyer --sometimes up to 16 hours a day during operations.    But then we got hit with the really big surprise.   After the first rocket attack on the Army barracks near Saigon, our ship got underway for DaNang to set up a Seadrone.  Using Seaplanes to patrol the Viet Nam coast line for gun runners.   Which meant 16 hours a day of nerve racking operations.    We set up Seadrones all around the coast line of Viet Nam till I finally  ended my association with the Navy in 1967. I left the Navy as an Radioman Second Class.   In 1967 the Navy decommissioned the 3 Seaplane Tenders in the Pacific and that marked the end of the use of Seaplanes.  That four years was such a difficult time, I took the key and threw it in the trash soon after my discharge.    So, no picture of that key…. but I will post some Seaplane pictures later.   Your probably wondering why I didnt just use a speed key on Naval circuits.    The Seaplane radio operators were Airdales and most of them couldnt send or receive over 12 wpm.  And no speed key can be adjusted that slow.  Plus, the Navy keying lines on those old tube transmitters caused quite a shock if you came across the contacts -- such as can happen when your moving weights on the dot arm.   I only used CW for one year in the Navy.   After the top secret clearance came through, I spent the next 3 yrs working  in the only room aboard ship that was air conditioned.  The Crypto Center :-)  The A/C was just to protect the sensitive eletronics equipment :-)   When I attended Teletype Repair school at San Diego, they gave me a temporary assignment aboard the USS Constellation Aircraft Carrier.  And during the 3 weeks I was aboard that 6000 man ship, we were on a training mission where planes were landing 24 hours a day on the flight deck.   The sleeping quarters for the radio crew were directly under the steam catapult that launched the aircraft.  So for that 3 week period I got only a few winks of sleep as the non stop catapult noise was earth shaking.   My heart goes out to those that had to endure life aboard Aircraft Carriers during constant 24hr day ops in war time conditions.   I can tell you they kept the chow halls open 24hours a day in order to feed 6000 crew members. And the food wasnt too bad :-)    The only time we had to send an SOS with CW was taking the great circle route to Japan via Alaska.  At 3am in the Aleutain Islands we lost the power to one of the screws in 45ft seas which caused the loss of steering.  So at 3am the ship went to general quarters.  We had no RTTY communications that night due to poor propagation so the only way to send a distress message was via CW.  NPG in Sfran was the only station would could copy on a freq around  2.7 Mhz.    By daylight they had power restored and all was well but we took in lots of water through the ventilator shafts.  Anyone who has ever sailed through the Aleutain Islands knows how rough those seas can be at any time of year...  And how sea sick a person can be even for an old sea dog :-)   On March 28, 1964,  I came back to the ship at Whidbey Island after 3 days of liberty to find it was GONE.  The ship had gotten underway to Alaska after the Good Friday Earthquake on March 27.  So I was stranded on Whidbey Island with nothing but the clothes on my back for 5 days till they flew me to Alaska to meet the ship at Kodiak.  The tidal wave that hit Kodiak completely destroyed the power generating capacity so our ship provided power to the city for almost 2 months.  The earthquake was a 9.2 and took 10 ton sea buoys and threw them far inland like they were match sticks.   After that we visited Alaska every 9 months during the summer R&R back in the states.   

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Most Telegraphers were paid by the word,  so sending fast was important.  Most speed keys send dots way fast and thats one reason why you hear speed keys being used on the ham bands sending dots at 35wpm and dashes at 20wpm.  If you just add more and more weight to the dot arm, it becomes unweidly heavy and that causes dot errors.  The  Extendadot designs that I have come up will allow easy adjustment as slow as 10wpm and it works as a sliding extender.  It replaces the weights on the dot arm and requires about 1 1/2" of room behind the key when its extended for slowest speed.  I've found the sliding extender works much better than just loading up your dot arm with heavier weights. Its very slender, light weight and works by extending the average weight past the end of the key when sending slower.   Some bugs send so fast they require 2 or 3  large 1oz weights to slow them down and then there is no way to change the speed with so many weights on the dot arm.    The Extendadot is very easy to adjust --- simply by sliding it back and forth on the dot arm.   The end of the Extendadot is taped for either  8-32 or 10-32 screw threads.  So a small weight can be easily added to the end in order to  slow it down for 10wpm -- if you wanted.  If your always changing the speed range, then the Vertical design allows easier speed changes by slipping on or off a small weight.  After many months of testing I finally came up with designs for the Original style keys (with the round dot arm) or the Lightning style keys with the flat bar dot arm as well as  the McElroy/TAC keys.    With the Lightning style keys, the extender attaches directly to your existing rectangular weight provided it has screw threads all he way to the bottom.  A few square weights dont have threads all the way through the weight.   See the pictures for the different designs. In a few months  I'll be making a  Trombone section that increases the slide length and makes it easier to fine tune it for your speed range.  Athough when the trombone section is fully extended it requires up to 3 inches of free space behind your key. The Trombone requires more hand fitting labor and I wont be making any of that type for a few months.   More pictures and other info at www.extendadot.com  I can make the Extendadot in various configurations for a very reasonable cost if you contact me via email @ (email spelled out to prevent spammers)

  SALES AT EXTENDADOT.COM

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This 1916 Vibroplex Original with Pinned Double Pivot is the best key I've ever sent with.   It has a very slow speed range (with two weights) and has perfect balance. I bought it from an estate sale and it had been sitting in the persons basement for over half a century.  And surprisingly is in very good condition mechanically.  As most of the keys that old had been really beat up. The person that owned this key was really partial to it as he inscribed the words "Hands Off" near the dot contact--  as you can see the pictures.    Between 1920 to 1923, Vibroplex changed the mechanical design to Bent Lug Single Pivot.  I've found the Pinned Double Pivot to be much more forgiving to send with and others who are lucky enough to own a Vibroplex with the pinned double pivot tell me the same thing.   I carved some finger pieces out of Murtle Wood and then used a drum sander to hollow out the centers.  It has a very light touch and is the key I use on the air most of the time.      If you look closely at picture #1 you can see the separate pivot for the dash arm used in the Pinned Double Pivot.  I own three Pinned Pivot Vibroplex Originals and they are all top of the line keys.  Most all other key manufactuers copied the Bent Lug design of Vibroplex after 1923.   If you have a chance to pick up a pre-1920 Pinned Pivot Vibroplex, dont pass it up :-)   The test of a great key is if it will produce the same quality dots from low to high speed.  Some keys can be adjusted for good dots at slow speed but the dots slowly fall apart as the speed is raised.  That occures if the key is out of alignment or there is wobble in the dot arm due to other issues.   

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