The following story is true. It is mentioned here because it may be
relevant to why people believe low Q parasitic suppressors are the leading
protectors from amplifier destruction. It is a war story, so it may be of
interest to those who like to hear them. It is also a radio story of a ham
operator.
During WWII, a German U-Boat was based in Singapore. Prior to leaving, a
German SS agent came aboard for an unspecified reason, wearing a suit and
carrying a black umbrella. Immediately, a buzz began aboard the submarine,
because submariners were superstitious by nature (with good reason, 95% of
them did not return) and black umbrellas were very unlucky. From the start,
this mission was in great danger, according to the majority of the crew.
The skipper, Heinrich Pahls, was not superstitious and ignored the crew.
After being out to sea for some time, it became necessary to refuel. Their
assigned refuel was in the Indian Ocean. They were #7 and last on the list
to be refueled. Because the Allies was searching everywhere, Henry stayed
submerged during the day and surfaced at night. All the others were finally
refueled and left. Then, the refueling ship was spotted and sunk, with no
other ships nearby and Henry left with almost no fuel.
According to protocol, Henry was simply to remain there and check into the
German net at Singapore at the assigned time and frequency. For three days,
he tried to do that. However, communications was never established. After
a couple of days, the German Navy assumed he was sunk and simply forgot
about the submarine and crew. Things were getting desperate, and the crew
grumbled even more that the black umbrella was the problem. However, Henry
had been an amateur radio operator in high school back in Germany and
remembered the formula for antennas. He calculated the length of an
inverted vee antenna and found things to make it, supported by the
periscope.
At the next time Singapore was on the air, Henry had the inverted vee
connected. He was standing on deck waiting for word from the radio
operator. Suddenly, a crew member burst onto the deck with the SS agents
black umbrella. He opened it and the wind carried it off. It was seconds
later that the radio officer yelled that radio contact was made with
Singapore. The crew cheered. All the crew members, except for Henry,
"knew" releasing the black umbrella was the reason for contact with
Singapore. Henry did not charge the sailor who stole the umbrella, and in
fact told the SS agent that he did not recognize who it was. If you asked
the sailors, probably 95% or better would have assured you it was releasing
the black umbrella that saved the ship.
Fuel did come. Heinrich Pahls survived and came to the United States,
becoming K7MMK. He died peacefully last year due to old age. He told me
this story, and others, while sailing in various spots around the world as
we did on many occasions.
I mention this story, because using nichrome wire in parasitic suppressors
may be similar to getting rid of the black umbrella.
K7FM Colin
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