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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!

On Saturday the NAQP CW contest was on and it's a great what I call "mini contest". For me it started at 2pm local time which is great as it allows me to get some things done before I get on the air. This is a 10 hour contest unless you are a multi-operator station then you can work  the full 12 hours. As I said the contest began at 2pm local time but I never got started until around 2:30 as I was BBQing lunch for Julie and I. I entered this contest as QRP and with it being basically a North American contest even with the propagation conditions being low there was lots of contacts to be made. Most of the code is sent at a decent contest speed but there were there those that were just pounding it out. I just skip by those and look for slower speeds (15-25 WPM) I find the time I take to figure out their call and exchange I could had made at least 2 other contacts, so I opt to make the other 2 contacts and let the high speed CW contester work those who can copy them. This year I only spent an 1.5 hours in the contest and netted 12 contacts. With my setup here at VE3WDM I'm thrilled to just get on the air and make some CW contacts. For this contest I used N3FJP's contest program and it was great, in the past I have always used N1MM+. Nothing against N1MM+ it is a great program and by no means did I stop using it because of any issues. I found N3FJP's contest programs easy to navigate since I have been using his logging program for ages. With my simpler station since I had moved I really don't need all the bell's and whistles N1MM+ has. So with my 12 contacts all on 20m my humble score was 120. I still submitted the score cuz you never know!!

On Saturday the NAQP CW contest was on and it's a great what I call "mini contest". For me it started at 2pm local time which is great as it allows me to get some things done before I get on the air. This is a 10 hour contest unless you are a multi-operator station then you can work  the full 12 hours. As I said the contest began at 2pm local time but I never got started until around 2:30 as I was BBQing lunch for Julie and I. I entered this contest as QRP and with it being basically a North American contest even with the propagation conditions being low there was lots of contacts to be made. Most of the code is sent at a decent contest speed but there were there those that were just pounding it out. I just skip by those and look for slower speeds (15-25 WPM) I find the time I take to figure out their call and exchange I could had made at least 2 other contacts, so I opt to make the other 2 contacts and let the high speed CW contester work those who can copy them. This year I only spent an 1.5 hours in the contest and netted 12 contacts. With my setup here at VE3WDM I'm thrilled to just get on the air and make some CW contacts. For this contest I used N3FJP's contest program and it was great, in the past I have always used N1MM+. Nothing against N1MM+ it is a great program and by no means did I stop using it because of any issues. I found N3FJP's contest programs easy to navigate since I have been using his logging program for ages. With my simpler station since I had moved I really don't need all the bell's and whistles N1MM+ has. So with my 12 contacts all on 20m my humble score was 120. I still submitted the score cuz you never know!!

Setting up

This is the first (but not last) year I participated in this contest, I have Larry W2LJ to thank as his blog posts regarding this contest inspired me. Both Julie and I made plans for this day, for me it was contesting and she hauled along all her cameras and gear and had a blast with her hobby photography.  The weather was fantastic with it being 31C in the shade but we were right on Lake Ontario with a nice breeze off the lake made it pleasant. I operated from Humber bay shores park which is just outside our condo. We brought along camp chairs and a portable table as we knew the park would be very busy and finding a picnic table would be out of the question. The contest started at 1pm local time which gave Julie and I time to pick out something to eat. (fruit crepes with maple syrup) Once we found our spot in the park and setup we sat and enjoyed the crepes as one has to fuel up before the contest.

The view from the op table

The rig I used was my Elecraft KX3 on external battery power, the antenna was the Chameleon CHA P mag loop antenna and my key was the Palm mini paddle   I was very happy with the Chameleon CHA P antenna, it only took me 5 min's to setup. It was very easy to tune but it was not until 1/2 way through my outing that I realized the KX3 had the preamp off! Once I put the preamp on finding the noise peak was much easier. I was very pleased with the setup and performance of the antenna. I was only able to operate for 2 of the 4 hours of the contest as Julie and I had dinner guests we had to be back home and prepare for. I only operated on 20m as this band was open and the QRP contacts were being heard. I was pleased that I made 11 contacts and I did have about 5 folks stop and ask questions about what I was doing. One gentleman told me that his dad was a ham and one of the young people that stopped told me she read about morse code in her history class! The band was in great shape and I was able to hear and work QRP stations all over the U.S. I made 2 contacts into New Jersey and for some reason I have never in the past made it to that state when doing portable field op's. I really enjoyed this contest and am looking forward to it next year.

Setting up the loop

The outdoor shack.

Chameleon CHA P

Fuelling  up before