I
acquired this ugly transmitter from a guy that said it came out of a
defunct radio museum in Houston, TX. It came with a label “The Hero of
Hallettsville”. Hallettsville is a small town west of Houston. Could
this transmitter have belonged to some ham struggling to stay on the air
as a hurricane roared around him? Perhaps he provided the only
communication with the outside world as roads flooded and telephone
lines went down. The true story behind this transmitter is close to
exactly that.
In two days in late June of 1940 south central Texas had over 22 inches of rain. This caused destructive floods in the area and seven people died in the Lavaca River at Hallettsville, Texas. Property and crop losses were estimated at more than $1 million. An article in the Sept 1940 issue of QST (pg 60) reports details from the ham perspective.
On Sunday morning, June 30, 1940 Hallettsville put out a plea to hams for help. The town was completely cut off, flooded, needed boats and doctors and had no outside communications. Water was 8 feet deep in the stores in town. Houston, Texas hams responded by gathering emergency equipment and heading for Hallettsville. Along the way water was over the running boards of their borrowed Texas highway department truck. At one point they found the road gone and those attempting to cross in boats up in trees where they stayed until the water receded. There the hams stopped and got on the air. One of their rigs was W5CVQ's 6L6 transmitter made up like a QSL-40 but with a padding condenser that could be switched in for 3.5Mc. Eventually the water went down enough that the Houston hams managed to get across and into Hallettsville to setup in City Hall. They were on the air for 24 hours handling requests for help and supplies, broadcasting flood reports and warnings and sending “personal messages of safety to relatives of the marooned populace”. During this time the little 6L6 rig proved to be a valuable help.
This little transmitter is certainly that 6L6 rig. It is built along the lines of the QSL series of CW transmitters described in QST before WWII and has an extra padding condenser that can be switched in via the toggle switch on the top panel. It looks like parts were scrounged from a variety of places including the kitchen trashcan. The broken and repaired panel, hacked tin can chassis and hasty paint job all say function before beauty. View the inside to this transmitter by clicking here (160KBytes).
The
QSL-40 series of transmitters were designed by Fred Sutter (W8QBW/W8QDK). The name comes from the size. It is about the size of a QSL card and
includes one tube, a crystal, plate current meter and a plug-in coil.
The QSL series of compact 6L6 transmitter designs appeared in QST
starting with the QSL 40 in February 1938 and ending with the QSL 25 in
April 1941. The QSL Push-Pull (June 1940) ran 600 volts on the 6L6
plates and could light a 100 watt light bulb to full brilliance. The 5
watt version described in December 1939 was at the other end of the
spectrum. It was a transformerless design using a voltage doubler off of
the 110 volt AC line to get 220 volts B+. That particular article
mentions that the operator should avoid touching the metal frame of his
key. The 6L6 (and its big brother the 807) appeared in transmitter
article after article for two decades.
The 1940 QST article mentions "lessons learned" that we can relate to:
- Portable so that it can be hand carried through any place the operator might need to go
- Powerful, selective and sensitive enough to work through interference
- 50 mile range,
- Can be powered off of utility AC power or batteries,
- Include a precut antenna.
I’ve never tried fixing the Hero of Hallettsville and putting it on the air. Any repairs would destroy its character and some of the history behind it.
For more on 6L6 transmitter see Gary's, WD4NKA, article at https://q5letterpress.blogspot.com/2015/02/the-legacy-of-simple-6l6-transmitter.html
