Could Agent Sonya Have Done It? (It: QRP CW on 40 meters in 1939)

The Soldersmoke blog pointed out an interesting post that was a focal point of a larger book review for "Agent Sonya: The Spy Next Door". The post's author was quite convinced that the key protagonist of the nonfiction tome could not and did not construct her own QRP communication rig in the 1930s as stated by the book's author.

I beleive Agent Sonya could have constructed the rig

More about the book on the publisher's site

The Soldersmoke post

The focal review post

The 1936 Radio Handbook

So, as I was saying:

I, for one, believe. I'll admit up front, I didn't have time to read the entire linked post. The following assumes that the issue was Sonya being able to build a transmitter in 1939 for use from Switzerland to Moscow. The short version? It should have been the picture of simplicity.

As an aside and a bit of a bona fides, we routinely QSO from San Francisco to Texas and beyond. That's the same distance as Switzerland to Moscow.

I grew up in a small town in New Mexico that had radio books for kids from the first half of the 20th century. The number of times I cursed the impossible to find "B battery"! That battery obsession inspires my belief that Sonya coulda done it though.

I looked up one of the books of the ilk that populated the Hobbs, NM library: the 1936 Radio Handbook. That informs everything below.

Let's start addressing Sonya's supposed issues till I run out of time.

The rig itself

First, I present to you the single tube CW transmitter from the 1936 Radio Handbook.

Here's the wiring layout

Soldering? Screws, a pair of pliers, and terminal lugs might have been just the thing!

The power supply:

The 6A6 requires a minimum of180 Volts on its plate circuit. Simple. Two B batteries for the plate current for a 6A6. Sonya would have needed another battery here and there, (e.g. the tube's heater filament), but this would have been the biggest deal, and it was available.

What about crystals?

Could they be had? Yeah, in 1936, they could.

I don't have time to look up the historic perspective, but assuming crystals existed for household radios of the 1930s, this seems like absolutely no big deal. (And I did take the time to leaf through the 1936 radio handbook and it wasn't a big deal as it turns out.) As a kid in the '70s, our hardware stores had tubes and crystals of all sorts for repairing household electronics.

I don't think the exact frequency is of any huge importance. The author seems a bit put out by the four decimal places. When we run Project TouCans, we start out at a frequency of 14.0575 MHZ, not because that level of precision is important, simply because that's the number. As we operate, we drift down to a stable frequency of 14.0573 MHz. If I write the frequency as 14057.4 kHz, we're down to a single digit of precision which might seem far less impressive, but would still be the same number.

The antenna:

Actually, the antenna set up sounds fine. The post's author seems to have intense feelings about banana plugs. We've used them for antenna connectors on Project TouCans. They work fine. Oh, and guess what? One of the ads in the 1936 handbook was for a crystal holder with??? You guessed it, banana plugs!

Morse code:

She needn't have learned all of Morse code, she was sending groups of five numbers. If you're going to learn Morse code with dots and dashes (the worst, yet most seemingly obvious way), the numeric digits are the easiest to make a system for.

Wood and metal working:

I mean, my radios are housed in a pineapple can. I realize these would have been tube rigs, but I still believe they could have operated without a case. Most of the rigs on soldersmoke podcast episodes of late have been mentioned as not having cases. And, oh! The transmitter in the handbook is pictured mounted to a board.

The recieve side of things:

First, who needs a receiver? She needs to find out once that the transmitter works. After that, it can be send and forget.

But let's play the game though and say she had to have a receiver. I turned on the Utah SDR, switched over to AM and listened to CW this morning. Sure enough, the strongest signals were clicks not tones. A series of clicks would communicate 'Listening' as well as anything else. Also? We're spies! Do we really have to use CW because we're being sent CW? Can we just pulse a tone three times?

I think she coulda done it :)

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