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One of this summer's radio workbench projects was to refurbish my Drake 2NT transmitter for this winter's NRR event. The 2NT was introduced in 1966 with the 'novice' ticket-holder in mind, selling for $129. It was the first and only CW-only transmitter produced by R.L. Drake.


As novice transmitters go, the 2NT was a cut above some of the others out there, boasting interesting features such as a built-in antenna changeover relay, sidetone oscillator, grid-block keying and built-in low pass filter.


The tune-up procedure was simplified as well and with Drake's reputation for quality construction, the 2NT became a popular choice for Novices and Generals alike.





My own 2NT was purchased, along with the matching 2C receiver and speaker/Q-multiplier combo over 25 years ago at a Washington state ham fleamarket. Ever since then they have been patiently sitting on the shelf, trying to catch my attention.

The motivation and much-deserved attention finally arrived this year after enjoying last winter's NRR and hearing several great-sounding 2NT's on 80, 40 and 15m CW. I operated the week-long Roundup with my homebrew 'Longfeller' at 5W output, in order to qualify for the QRP category.

6AG7 - 6V6 'Longfeller'

I have to admit, the Novice Rig Roundup, was one of the most enjoyable contests I have entered in many years! Hearing many rigs from the 50's and 60's sounding so good was just a bonus. It was particularly gratifying to be able to work the midweek daytime activity on 15m ... a luxury that we may not enjoy now for several years if most of the long term solar forecasts are correct.

I eventually ended up with 68 contacts, but at 5W, it was a challenge ... most of my many 'CQ NRR' offerings were unanswered, so it was mostly a 'search and pounce' operation. With this in mind, I soon decided that next time, I'll get the 2NT ready to go and hopefully, with a little more oomph, can attract some callers.

Each entrant received an NRR certificate - a nice touch

Rather than hunt down and purchase the individual replacement electrolytics, especially the multi-unit can capacitor which was impossible to source, I ordered the '2NT re-cap kit' from Hayseed Electronics. They supply replacement kits for several boatanchors and are able to make and stuff multi-section can capacitors to match the original size and specs ... and all at affordable prices.

After cleaning the chassis and all of the switches, re-tubing with new tubes and removing / replacing all of the electrolytics, the 2NT was ready to go. Using a crystal for excitation, the following results were obtained:

         80m 103W input 75W output efficiency = 73%
          40m  92W input 65W output efficiency = 71%
          20m  92W input 65W output efficiency = 71%
          15m  92W input 55W output efficiency = 58%
          10m  92W input 50W output efficiency = 54%

Keydown voltages averaged ~520V while plate current ranged from 170-200ma. All-in-all, right on target and not bad for a 51 year old transmitter!

The 6EA8 modified Pierce oscillator in the 2NT seems particularly 'crystal-friendly', as every old style FT-243 style crystal that I tried sounded great. Even the newer ones from AF4K using a modern HC-49 crystal slab mounted inside a vintage FT-243 holder sounded great and worked perfectly.

My newly refurbished 2NT - ready to go

A couple of days later, I returned to the bench to take some blog photos of the rig delivering power into the wattmeter. When I turned the 'stby' switch to 'transmit', the plate current suddenly shot up (with no keying) and the meter on my Variac supply indicated over an amp being drawn by the power transformer ... all with zero output and no crystal plugged-in!

A look at the schematic diagram revealed that with the grid-block keying system, the final amplifier's cathode is always grounded and a low voltage negative bias applied to the grid keeps the plate current cut-off until being keyed ... with cut-off bias missing, plate current will soar, along with transformer primary current. I suspected that something had gone haywire with the bias supply.


A quick check of the 2NT's printed circuit board containing the bias system components among others, indicated a discolored silicon rectifier (D5) in the bias supply. An in-circuit measurement revealed that it was indeed shorted, basically supplying raw AC across the filter capacitor and shorting out the transformer winding, quickly elevating the transformer's temperature in the bargain ... not good.

Although the diode only has to handle a small amount of current, it was mounted with a heat-producing 2W resistor straddling its top surface. As well, the phenolic circuit board was noticeably discoloured from the heat. I suspect this was the main reason that D5 eventually failed.

My 2NT was an early one, serial #670, so perhaps this parts-arrangement was re-engineered in later models. Once the diode was replaced with a much smaller modern one, of twice the rating, everything returned to normal. The last thing I would want to do at this stage is to burn out the transmitter's unique power transformer, undoubtedly impossible to replace nowadays.

The next bench project will be to refurbish and improve the stability of my Heathkit VF-1 VFO and to mate it with the 2NT.

'55 QST VF-1 ad

There are several things that can be done to a stock VF-1 to improve its performance. Its wonderful backlit green dial will bring back a lot of memories from my teenage operating days with the VF-1 ... most, but not all of them, warm and fuzzy.



Another small quirk noticed on my 2NT is the meter mount. My early model has the meter mounted so low that the silk-screened 'PLATE CURRENT MA.' label is not clearly visible when looking straight-on.

My #670

Later models show that this was changed by moving the meter a little higher so that the label can be easily seen without having to look down inside. Nothing major, but something apparently missed during the initial panel design.

Later models

I'll have more to say about the 2018 NRR later, but if it's something that you may be interested in trying and you don't yet have a suitable novice-style rig, it's not too late to start looking, building or refurbishing.

You can read many interesting soapbox comments and see some nice NRR station photos from the previous two events here and here, but read with caution as you could easily get hooked. I find pages like this very inspiring and they remind me of the days when QST would publish photos, soapbox comments and exacting equipment descriptions used by each section winner in the annual November Sweepstakes contest.

Winner's gear in '55 CW SS - remember these?

NRR activity really skyrocketed last winter and I expect that it will be an even busier event next time. There are several CW contests that I'm looking forward to this winter and the NRR is right near the top of the list. I hope to see many of you in the 2018 NRR!

This week's Sun

Well, just when the sun was showing some nice signs of growing quiet for the upcoming winter, Cycle 24 has once again demonstrated that it's not going down without a fight.



For the past few weeks of quiet solar conditions, low band propagation, in spite of the time of year, had been performing well, with both 40 and 80m having a nice level of evening CW activity stretching out to the central states and to the east coast.

That all changed this week when the Sun let loose with a series of powerful flares, one of which was the strongest in a decade ... all very surprising for a Sun that has already shown us many days of spotless conditions as it winds its way to the bottom of the cycle.





With Solar Cycle 24 being one of the weakest on record, it has shown levels of activity on the way down that could rival the past few much stronger cycles in their waning years. Another oddity for this cycle was its 'double-peak', not unusual per se except that 24's second peak was the stronger of the two.

courtesy: http://www.solen.info/solar/

With the recent flaring and accompanying radio blackouts, HF propagation has been poor and with auroral conditions forecast for the arriving CMEs, it may take some time to recover, especially on LF and MF. But it may not be all bad.

Disturbances like this will normally affect E-W, polar and Trans-Atlantic paths more than N-S paths. Oftentimes, paths to South America on MF and HF will be enhanced as will the Trans-Pacific path, so all is not lost.

There are many websites devoted to providing a 'heads-up' to what might be coming geomagnetically-speaking. Two of my favorites are here and here.

The more northerly you are, the more disruption you will notice and for some reason, VE7 land seems particularly in-tune with solar perturbations as the slightest hiccup on the Sun seems to immediately wreak havoc here. Even amateurs a hundred miles to the south or southeast, enjoy markedly less disruption than us out here on Canada's western edge ... for some reason, we seem more tied-in to the auroral zone activity than we should, given our westerly location. Perhaps the zone dips lower in this region than it does further east but it is something I have observed on LF and MF for decades now.

It seems as though the first hit has just arrived so hold on to your hats:

It's almost that time of the year when, once again, the '29ers start preparing for the winter Bruce Kelley 1929 CW Party. A recent posting on the Yahoo AWA (Builder's) Group by Lou, VE3AWA, reminded everyone that there were only 108 more sleeps before this year's Party.



In case you're not familiar with the 'BK', it's a winter CW event celebrating the early days of amateur radio.

Transmitters used for the event must be self-excited only ... no crystals are allowed ... and the tube(s) used must be those that were available in 1929 or earlier. It's an eye-opener to hear how the band must have sounded in the early days of amateur radio CW... even better if you're making those beautiful sounds yourself.

The 'BK' usually spawns a flurry of construction, so if you think it is something that might interest you, you have until December to get ready! Unfortunately many aspiring '29ers always leave it too late and inevitably run out of time before any last glitches can be overcome.

For many builders of  '29-style gear, especially transmitters, the two-weekend December event is the highlight of the year as it gives them the opportunity to get on the air with their early-style rigs and work as many other '29ers as they can.

Every year there are numerous transcontinental CW contacts made with the simple, usually single-tube, self-excited oscillators that look as if they would have difficulty just being heard across town! Tuning in to the BK Party may be the closest thing you can find to a 'time machine' these days, as a small section of the CW bands (160-40m) take on the same sounds you would have heard when tuning across these bands in the late '20s.

When I first listened to a BK Party several years ago, I was surprised at the wide range of signal quality coming from these faithfully reproduced exhalers, running the gamut from the 'almost Collins-like' MOPAs to the unique sounding raw-AC notes coming from some of the one-lungers.

Most of the stations I have worked in past BK events were running less than 10W input yet, even with the terrible conditions experienced in the last two events, their signals were making it across the continent on the low bands ... and all were having a great time doing it!


Larry's (NE1S) TNT makes it back to the west coast every year in the BK Party.



Shown above is a fine little TNT built by Kevin, WB2QMY, in New York. It uses a very affordable UX-201A triode, originally manufactured in 1925 for radio receivers. Although Kevin's TNT puts out barely 2 watts on 80m CW, we had no trouble working each other in the BK QSO Party. If you build it, they will come!


If you've ever entertained thoughts of wanting to participate in the '29 QSO Party, this late-summer 'heads-up', could be just what you need to make it happen ... there is still plenty of time to put something together for this year's event. Here is the specific information for this year's BK Party.

There is plenty of information available right here on my blog that will answer many of your initial concerns surrounding tubes, circuits and components:

An Introduction To Building ... '29-Style

'29-Style Transmitters ... What To Build? - Part 1

'29-Style Transmitters ... What To Build? - Part 2

As well, my own website contains several detailed construction procedures on various transmitter styles used back in the day ... and an inspirational 'Gallery of '29-Style Transmitters' from other builders. In addition, there is a lot more '29-specific information in this blog, all of which can be found here, for several nights of bedtime reading!

Should you decide to take on a simple transmitter for this year's party (and there are dozens of participants hoping that you will), here are a few things to keep in mind:

You don't need much power to make contacts ... just a few watts will do it. If your antenna system is efficient and you can hear reasonably well, expect to work '29ers all across the continent.

Your transmitter does not have to 'look pretty'! You can breadboard up something with modern components and as long as the tube-year qualifies, you're good to go. Too many get bogged-down with making a showpiece ... that can always come later.

I, and others, have found Hartley oscillators to be the easiest to get going and often produce the best notes. Although the power limit this year has been increased to 25 watts DC input, just 2 or 3 watts coming from a simple Hartley will guarantee you a ticket on the BK time machine.

A wonderful source of advice, inspiration and even help with parts, can be had by joining the AWA (Builders) Group.


For now, I'll tempt you with the basic information regarding the QSO Party as published by the 'BK' sponsor...the AWA.

The Bruce Kelly 1929 QSO Party is a yearly AWA sponsored event where participants build their own transmitters using the designs, techniques, and tubes that were available in 1929 and earlier, and then put those classic transmitters on the air and try to contact as many other 1929 stations as possible.  Since they use early designs, it is a cacophony of whooping, chirping, buzzing, clicking, drifting, swishing, swaying, warbling, and other interesting signals.   This is what ham radio sounded like in 1929 and for two weekends in December its 1929 again on the ham bands.

It's almost that time of the year when, once again, the '29ers start preparing for the winter Bruce Kelley 1929 CW Party. A recent posting on the Yahoo AWA (Builder's) Group by Lou, VE3AWA, reminded everyone that there were only 108 more sleeps before this year's Party.



In case you're not familiar with the 'BK', it's a winter CW event celebrating the early days of amateur radio.

Transmitters used for the event must be self-excited only ... no crystals are allowed ... and the tube(s) used must be those that were available in 1929 or earlier. It's an eye-opener to hear how the band must have sounded in the early days of amateur radio CW... even better if you're making those beautiful sounds yourself.

The 'BK' usually spawns a flurry of construction, so if you think it is something that might interest you, you have until December to get ready! Unfortunately many aspiring '29ers always leave it too late and inevitably run out of time before any last glitches can be overcome.

For many builders of  '29-style gear, especially transmitters, the two-weekend December event is the highlight of the year as it gives them the opportunity to get on the air with their early-style rigs and work as many other '29ers as they can.

Every year there are numerous transcontinental CW contacts made with the simple, usually single-tube, self-excited oscillators that look as if they would have difficulty just being heard across town! Tuning in to the BK Party may be the closest thing you can find to a 'time machine' these days, as a small section of the CW bands (160-40m) take on the same sounds you would have heard when tuning across these bands in the late '20s.

When I first listened to a BK Party several years ago, I was surprised at the wide range of signal quality coming from these faithfully reproduced exhalers, running the gamut from the 'almost Collins-like' MOPAs to the unique sounding raw-AC notes coming from some of the one-lungers.

Most of the stations I have worked in past BK events were running less than 10W input yet, even with the terrible conditions experienced in the last two events, their signals were making it across the continent on the low bands ... and all were having a great time doing it!


Larry's (NE1S) TNT makes it back to the west coast every year in the BK Party.



Shown above is a fine little TNT built by Kevin, WB2QMY, in New York. It uses a very affordable UX-201A triode, originally manufactured in 1925 for radio receivers. Although Kevin's TNT puts out barely 2 watts on 80m CW, we had no trouble working each other in the BK QSO Party. If you build it, they will come!


If you've ever entertained thoughts of wanting to participate in the '29 QSO Party, this late-summer 'heads-up', could be just what you need to make it happen ... there is still plenty of time to put something together for this year's event. Here is the specific information for this year's BK Party.

There is plenty of information available right here on my blog that will answer many of your initial concerns surrounding tubes, circuits and components:

An Introduction To Building ... '29-Style

'29-Style Transmitters ... What To Build? - Part 1

'29-Style Transmitters ... What To Build? - Part 2

As well, my own website contains several detailed construction procedures on various transmitter styles used back in the day ... and an inspirational 'Gallery of '29-Style Transmitters' from other builders. In addition, there is a lot more '29-specific information in this blog, all of which can be found here, for several nights of bedtime reading!

Should you decide to take on a simple transmitter for this year's party (and there are dozens of participants hoping that you will), here are a few things to keep in mind:

You don't need much power to make contacts ... just a few watts will do it. If your antenna system is efficient and you can hear reasonably well, expect to work '29ers all across the continent.

Your transmitter does not have to 'look pretty'! You can breadboard up something with modern components and as long as the tube-year qualifies, you're good to go. Too many get bogged-down with making a showpiece ... that can always come later.

I, and others, have found Hartley oscillators to be the easiest to get going and often produce the best notes. Although the power limit this year has been increased to 25 watts DC input, just 2 or 3 watts coming from a simple Hartley will guarantee you a ticket on the BK time machine.

A wonderful source of advice, inspiration and even help with parts, can be had by joining the AWA (Builders) Group.


For now, I'll tempt you with the basic information regarding the QSO Party as published by the 'BK' sponsor...the AWA.

The Bruce Kelly 1929 QSO Party is a yearly AWA sponsored event where participants build their own transmitters using the designs, techniques, and tubes that were available in 1929 and earlier, and then put those classic transmitters on the air and try to contact as many other 1929 stations as possible.  Since they use early designs, it is a cacophony of whooping, chirping, buzzing, clicking, drifting, swishing, swaying, warbling, and other interesting signals.   This is what ham radio sounded like in 1929 and for two weekends in December its 1929 again on the ham bands.

HM - 221 kHz Hamilton, Ontario

This coming weekend will see another CLE challenge. This time the hunting grounds will be all inclusive: 190-1740 kHz. As well, there are two options, HOME and DX as explained below.



For those unfamiliar with this monthly activity, a 'CLE' is a 'Co-ordinated Listening Event', as NDB DXers around the world focus their listening time (usually) on one small slice of the NDB spectrum.

Summertime CLEs can often be challenging, not because of poor propagation but more likely, summer lightning storms ... hopefully it will be quiet for your location.

When tuning for NDBs, put your receiver in the CW mode and listen for the NDB's CW identifier, repeated every few seconds. Listen for U.S. NDB identifiers approximately 1 kHz higher or lower than the published transmitted frequency since these beacons are modulated with a 1020 Hz tone approximately.

For example, 'AA'  (Fargo - ND) transmits on 365 kHz and its upper sideband CW identifier is tuned at 366.025 kHz while its lower sideband CW ident can be tuned at 363.946 kHz. Its USB tone is actually 1025 Hz while its LSB tone is 1054 Hz.

Often, one sideband will be much stronger than the other so if you don't hear the first one, try listening on the other sideband.

Canadian NDBs normally have an USB tone only, usually very close to 400 Hz. They also have a long dash (keydown) following the CW identifier.

All NDBs heard in North America will be listed in the RNA database (updated daily) while those heard in Europe may be found in the REU database. Beacons heard outside of these regions will be found in the RWW database.

From CLE organizer Brian Keyte, G3SIA, comes the usual 'heads-up':


Hi all

Our 222nd Co-ordinated Listening Event, 'DX and HOME', starts on Friday
and runs for an extra day. First-time CLE logs will also be very welcome
of course.

Days: Friday 25th August - TUESDAY 29th August
Times: Midday on Friday to Midday on Tuesday, your LOCAL time
QRG: Normal LF/MF frequencies (190 - 1740 kHz)
NDBs: Normal DX and 'HOME' ones (not DGPS, Navtex or Amateur)

There are two parts (you can listen for either or both of them):

DX:
Please try to log NDBs that are over 2,000 km / 1,250 miles from you.
(If you don't have details of the distances of NDBs from you, please see
the end of this email)

HOME:
If you have any, please log the NDBs in YOUR OWN radio country.
For listeners in AUS, CAN and USA, that means your State or Province.
Our full list of radio countries can be found at:
http://www.ndblist.info/ndbinfo/countrylist.pdf
(If you also mention any of your home regulars NOT heard, it will help
others to know about NDBs, maybe DX to them, that may not be active)

Please post your CLE log to the List in a plain text email if possible,
with 'CLE222' at the start of its title and showing on each log line:

The full Date ( e.g. 2017-08-25 or just the day number 25 )
UTC (the day changes at 00:00 UTC).
kHz - the nominal published frequency
The Call Ident.

Please put those four main log items FIRST, with any other optional
details such as location and distance LATER in the same line.

Your log will be more interesting if you keep the two parts, DX and HOME,
separate in it. Any UNIDs that you come across will also be of interest -
in a separate, third, part of your log please.
If you send interim logs, please make sure that you also send a 'Final' log
showing ALL your loggings for the CLE.

I will send the usual 'Any More Logs?' email at about 17:00 UTC on
WEDNESDAY so you can check that your log has been found OK.
Do make sure that your Final log has arrived on the list by 08:00 UTC
on Friday 1st September at the very latest.
Joachim hopes to complete the combined results on the Saturday.

Good listening
Brian
----------------------------------------------------------
From: Brian Keyte G3SIA ndbcle'at'gmail.com
Location: Surrey, SE England (CLE coordinator)
----------------------------------------------------------

(If you wish you could use a remote receiver for your loggings,
stating its location and owner - with permission if required.
A remote listener may NOT also use another receiver, whether
local or remote, to obtain further loggings for the same CLE.
The HOME radio country and the distances would be based on
where the receiving equipment is located)

DISTANCES TO NDBs FROM YOUR LOCATION

The Great Circle program GcmWin by SM3GSJ can produce a nice great circle
map centred on your location - see http://www.qsl.net/sm3gsj/

Users of Michael's NDB Handbooks will already have their distances and
bearings to the NDBs.

Alex's WWSU program has a facility to create a map showing the areas
inside the 2000 km circle.
To create this,
click on 'Tools'
click on 'Station Radar'
select Range from “2000” to “10000” km
select “show NDB stations”
click on “Generate Image”
click on “Save To File”
That will create a text-file containing information on the selected NDBs.

The REU/RNA/RWW Database provides a powerful way of finding which
NDBs to search for:

1) Go to the signals screen using -
http://www.classaxe.com/dx/ndb/reu?mode=signals
If you are in North America, replace the reu above with rna
If you are not in Europe or North America, replace the reu with rww

2) On the Range line, put your *Locator in the 'From GSQ' box (e.g. mine
is IO91tg) The DX fields become enabled when a GSQ is entered.

3) Enter 2000 in the first DX field, leave the second blank and leave the
units as 'km' (or use 1250 and 'miles', if you prefer)

4) Select 'Only Active' and press 'Go'.
Now you only see NDBs that are over 2000 km from you.

Change 'Show' in the top line to 'All Results'.
The other fields are also active - e.g. you could enter specific States or
Countries in the Location line to limit the search to the NDBs there.
And/or you could click on 'Map', then on 'Go' and uncheck 'Clustering'

*If you do not know your Locator you can quickly find it from your
Latitude/Longitude (and vice versa) by using:
wingrid.exe V4.1 - freeware from W4SM 

These listening events serve several purposes. They:

• determine, worldwide, which beacons are actually in service and on-the-air so the online database can be kept up-to-date

• determine, worldwide, which beacons are out-of-service or have gone silent since the last CLE covering this range

• will indicate the state of propagation conditions at the various participant locations

• will give you an indication of how well your LF/MF receiving system is working

• give participants a fun yet challenging activity to keep their listening skills honed

Final details can be found at the NDB List website, and worldwide results, for every participant, will be posted there a few days after the event. If you are a member of the ndblist Group, results will also be e-mailed and posted there.

The very active Yahoo ndblist Group is a great place to learn more about the 'Art of NDB DXing' or to meet other listeners in your region. There is a lot of good information available there and new members are always very welcome. As well, you can follow the results of other CLE participants from night to night as propagation is always an active topic of discussion.

If you are contemplating getting started on 630m, listening for NDBs  is an excellent way to test out your receive capabilities as there are several NDBs located near this part of the spectrum.

You need not be an ndblist member to participate in the CLEs and all reports, no matter how small, are of much value to the organizers. 

'First-time' logs are always VERY welcome!

Reports may be sent to the ndblist or e-mailed to either myself or CLE co-ordinator, Brian Keyte (G3SIA), whose address appears above.

Please ... give the CLE a try ... then let us know what NDB's can be heard from your location! Your report can then be added to the worldwide database to help keep it up-to-date.

Good hunting!

HAKUNA MATATA

It may not have been the YASME but the recent voyage of the HAKUNA MATATA had all of the radio fun that one might ask for during the mid-summer doldrums! (more later for those too young to recall the YASME)



Crewed by Mark (VA7MM) and YL May (VE7MAY), Toby (VE7CNF) and XYL Nancy, the 31' Benateu recently completed a 14-day circumnavigation of Georgia Strait's Gulf Islands. This is a yearly adventure that has been successfully completed for the past few summers and looks as though it may now be an annual tradition.

Normally, the crew kept up regular radio contact on HF as well as on VHF when possible but this year saw a major departure.

In previous summers, near the end of the voyage, the crew has always visited us here on Mayne Island for an afternoon of vittles and libation before heading for home. There is always a good amount of time spent recalling the past-year's radio activities, winter projects and reminiscence of the 'good old days'. Last year, just as the party was ending, I jokingly suggested that 'next year', it would be cool to work them from the boat on 630m.

Although there was no immediate commitment, I knew that the seed had been planted, and with three of the four crew being engineers, I suspected it might be hard for them to resist, and ... just before departure, the local bunch of 630m ops were put on alert to be watching for CF7MM/mm on 475 kHz CW as they would be attempting to work us from three different overnight anchorages during their summer voyage!

Evidently Toby had been working quietly during the winter to make this become a reality. Here are some pictures of the system along with Toby's (the system's builder) comments.

Variometer and matching transformer

I have attached photos of the CF7MM/MM 630m setup on Hakuna Matata. The lower black toolbox holds a variometer with selectable taps and a matching toroidal autotransformer with selectable taps. At the base of the antenna is another series loading coil.

Wire vertical and loading coil

The antenna wire is 14 ga 38 ft long with plastic Unadilla "END-sulators" at each end. Ground was the boats's cast steel keel and a couple of 30 ft wires near the gunnels. The rig is an IC-746 with my power-mixer transverter. Transmit power was about 20W TPO.

Toby (VE7CNF) working the pileups!

Tuning and matching was done with a resistive voltage divider setup, signal generator, and portable oscilloscope. Once the matching was figured out, I could re-tune the variometer to give a dip on the transverter's RF voltmeter and check that we had the same RF voltage as with a dummy load connected.

Tuneup

The antenna equivalent circuit is approximately 100 pF in series with 27 ohms. Coil losses were 23 ohms for about 50 ohms total load resistance, so the matching autotransformer was not used. The base loading coil is approximately 170 uH and the variometer is 950 uH, for 1120 uH total inductance.

The route, heading north from Vancouver

We tried disconnecting the gunnel ground wires and leaving only the keel, and found that the antenna capacitance and resistance did not change. When we disconnected the keel and left only the gunnel wires, the antenna capacitance dropped to about 87pF and antenna resistance dropped by a few ohms. It appears that the keel provided most of our ground coupling to sea water and it would have been a sufficient ground on its own.

More details of Toby's 630m transverter as well as a practical 630m antenna tune-up procedure can be found on his website here.

All-in-all, I think the 630m operation was a great success and very likely the first-ever 630m marine mobile operation on that band, as I don't recall this happening anywhere else over the years. It was also a great way to pay homage to the band's original maritime heritage where its quality groundwave and skywave capabilities were used to advantage for so many decades safeguarding mariners worldwide.



Maritime mobile operation on the amateur bands has some great history behind it, including the yacht YASME. In the mid-50's, Danny Weil was the first ever amateur to undertake DX'pedition style operations via sailboat, as he visited numerous rare islands in the Caribbean and South Pacific.

Danny on the YASME - courtesy: www.gm3itn.co.uk

Original YASME QSL -  courtesy: http://hamgallery.com/

His exploits were regularly published in CQ magazine at the time and always made for exciting reading as Danny would eventually wreck three YASMES over the years! His adventures laid the groundwork for future island-hopping DX operations such as those undertaken by Gus Browning (W4BPD), Don Miller (W9WNV) and all that followed ... I'm sure they would all have enjoyed working the HAKUNA MATATA as well!