| I built my first RC ship, a STERLING MAMBO, in 1955. It was
powered with a K&B TORPEDO "15", no throttle, just full bore. the
receiver was a home built, made from an ESSCO LORENZ TWO SOFT TUBE
KIT, voltage "B" battery of 45 volts, made from cutting down a
portable AM Broadcast battery, rated at 67 1/2 volts. Buy two
batteries, cut both down, and have pieces to put together to make a
third. "A" battery was a couple of pencells in parallel, or one
"D" battery. These receivers were "CARRIER" only operated;
transmitter carrier "ON" for control, "OFF" for whatever-else. At
this time, single channel "TONE" operated radios were on the
market, usually only as magazine schematics. Early SCHMIDT
mult-channel tone radios were on the market and the original
BRAMCO five channels also. The SCHMIDT was based upon ED
ROCKWOOD's early pioneering efforts. I believe the first MULTI
CHANNEL servos for general over-the-counter sale were made by DMECO
(Harold DeBolt).
The transmitter I used, I also built from a kit by the little
outfit in Higginsville, "ACE". It was a ground based box, about a
foot long, eight inches deep and 8 inches high with a nine (9) foot
whip antenna (three screw thread joints). The transmitter power
was rather exotic for the time. I used a BB54-A 2 volt wet cell
powering a filtered output, vibrator power supply, supplying 135
volts of "B" and used a length of nichrome wire, wrapped around a
form, to make a dropping resistor for the 1 1/2 volt "HARD" tubes,
a 3A4 and a 3D6. A lot of guys were using what they called a "MAC
II" transmitter in those days, a power amp rig putting out 5 watts.
But they had drawbacks, such as fracturing the crystals, if you
powered up without all your antenna up and stuff like that there.
Mine only put out 2.5 watts and was called a "MOPA" circuit, MASTER
OSCILLATOR, POWER AMPLIFIER. WORKED GOOOOOOD!!!
For the control in the airplane, the receiver triggered a
"NEOMATIC" relay which in turn, activated a "NEWX" escapement,
motive power being a wound up rubber band back to the tail of the
airplane. RUDDER ONLY, not even ENGINE CONTROL. And this
escapement was not one-position self-neutralizing. You had to
remember what the last command you gave the airplane because
control was right-left-right-left and on and on. Rmember the last
command or you might get the next one wrong! We thought it was
GREAT, just GREAT!
That MAMBO was a nice ship, but I had built U-CONTROL and free
flights for years and knew the wing was designed week. I put a
couple of plywood spar joiner reinforcements in it and had no
trouble. A lot of guys broke wings on this airplane and "AUGERED"
hard! Just think, the BABCOCK MARK II Compound Escape was just
about on the scene, and between it and the CITIZENSHIP COMPOUND
Escapement, there was only ONE NEUTRAL. One push on the MICRO
SWITCH 6 foot long keying cable I held in my hand would in the
future, ALWAYS give me RIGHT RUDDER.
Can you imagine, unassisted ROGs, straight flight, turns, rolls,
split S's and, even spins, all at FULL THROTTLE ('cause there ain't
nothin' else) and EVERY LANDING a "DEAD STICK". A lot of guys had
fly-a-ways because of receiver trouble, wound-down escapement
rubber, sticking escapement "CLAWS", nervousness at spiralling a
bird down that had too much altitude, disorientation with high
altitude and just plain naot able to make headway against a stiff
wind with an airplane that wanted to climb steeply all the time.
P.S., I NEVER HAD A FLY-AWAY. Just lucky I guess.
Oh, yes, and then there were those guys that flew CITIZSHIP (brand)
rigs on 465 MHZ. 27.255 MHZ and 465 were the only legal
frequencies non-hams could use. (That was CITIZENSHIP brand, from
VERNON McNabb, one of the first pioneers in production RC gear;
actually the first, I believe, and the ONLY guy for a long time
that produced stuff on 465. BABCOCK came along later with his.
CASCADED ESCAPEMENTS IN THE NEXT FILE REPLY, with BABCOCK MARK IIs,
yet, in a DeBolt CHAMPION, circa 1956?????????
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| I enjoyed hearing your RC nostalgia stories. Hope you continue,
and others with such experiences should speak up too. I've been
following Eloy Marez's commentary in Model Builder on Wee RC,
where some folks are building the smallest systems possible --
one fellow has a hand launched glider with a wingspan of about 12
inches, and a weight of just a few ounces (I know that Ken
Willard built a peanut-sized RC using modern equipment). The
"glider" is just a stick with wings! So there is some interest
in keeping the old equipment going, and there is a place for that
still.
My first try at RC, in 1959 or so, aborted on the workbench. I
sent away for an "amazing" RC radio kit, cost all of $20. That
was as big a chunk as I could afford, being enlisted in the Air
Force at the time. The kit was called the Vanguard. It used a
little sub-minature tube (not the gas tube, the other one) that
soldered into the receiver PC board (pc boards were futuristic
back then). The transmitter was a 12" long about 3" square box
with a button on it (actually I think it was a switch). Anyway,
the whole dream went south when I hooked the receiver up for a
power on test and reversed the B+ and filament connections.
Couldn't find anyone who knew anything about it, couldn't find
replacement parts in the hobby shop; they didn't even stock
escapements. Very embarassing, since I was a radio tech at the
time.
I never forgot that though. I decided then that RC was just too
complicated and that sooner or later the technology would work.
Played with sports cars and sailboats (believe me, on the skip a
meal to buy oil for the car end of the scale) for 20 years while
my life settled down so I could go back to model planes -- I
watched the technology for that time, though, never got too far
from it all.
A lucky break came just a few months ago when a friend gave me
the last 20 years of RCM -- including the first issue! I read
every one cover to cover, and even built a single channel .020
job, the DQA from about 1964. Haven't flown it yet as the
Colorado winds have been present -- in the fall and winter they
die down, and I will fly it then.
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| Sort-of----1956.... I said that DeBolt probably had the first
successful multi-servos for radio control flying and, indeed, I
think he did. But there were lots of homemade rigs seen in the
magazines; never any plans, just pictures. One of these was by a
fellow named Taylor. His did get into limited production I
believe, mainly on the east coast. However, DeBolt marketed his
nationally and everybody flew (some crashed) until Howard Bonner
came along with his first mult-servos, completely enclosed in a
square can, in about 58??? They were tremendous, except for one
little fact. He had a motor that ran its armature shaft on steel
ball bearings which circulated in a plastic race that was part of
the motor case. When a little wear in the plastic occurred, the
armature wobbled, struck the internal magnet and FROZE right there;
INSTANT CRASH. They were recoverable by changing the motor or
pressing in an oilight bearing instead of the ball bearing.
Bonner's SERVO came along after his former compund escapement and
regular escapement. His compund could activate his regular through
third position contacts and Stuart BABCOCK invented and air bleed
system gimmick that could be used to obtain two speed engine
control.
Bonner never let grass grow under his feet and came out with the
VARICOMP, using a cam plate and torquerod with cam follower. Since
John Worth and others were working with what they called "CASCADED
ESCAPEMENTS, which were two compound escapements electrically
hooked and switched together so that one push of the transmitter
button gave right rudder, two gave left rudder, three gave up
elevator and four gave DOWN elevator. A quick blip gave engine
control. I quickly took two of the NEW BABCOCK MARK II COMPUND
ESCAPEMENTs and made my own switching to do the same thing, still
with NO engine control.
About this time a place callled COBB HOBBY in Georgia (now it's
LANIER Arf Models) brought out one of several servomechanisms they
marketed with a four-position compund escapement, complete with an
add-on stick box for the transmitter. With this, you pushed the
stick to where you wanted and it gave the right control. Real
NEAT; and still I had no engine control. By the way, I was flying
the original DeBolt Cahmpion with inverted K&B 15. Wouldn't fly on
a 10-3 T.F., but would fly fine a 10-2. Later I put a torp 19 in
it and had a real tiger. Still flying a LORENZ CW receiver,
although it was a new one I had built; now called a CASCADE QUAD.
Still used 45 volts, but had a screen grid bias of 22 1/2 volts and
two diodes in the circuit; still an RK61 front end and XFY1 relay
driver. Still used this receiver when I built a BABCOCK BREEZY JR.
with extended wing and a lot os sheet balsa and with a TORP 15
instead of the requested .049.... What a bomb. Flew it on
proportional rudder at 1957 NATS at WILLOW GROVE, Pa. Got shot
down by MACII tuning up in hangar. Lots of airplanes bit the dust
that day because of that.
Bonner and his VARICOMPS had a problem; the nylon cam swelled with
heat and age and jammed the cam follower;.....CRASH!!! But he
fixed it and you could do a lot of good flying with it, regular,
with kick-up elevator, and cascaded for both up and down, with
engine control. Ken Willard modified a BABCOCK MARK II with
special claws and followers and using the COBB STICK BOX, won a
NATS in INTERMEDIATE with his "POOR MAN'S MULTI!
The problem with MULTI CHANNEL to this time was many faced.
Besides the failure of the servos, the "REED" Radios were just not
dependable. These radios, dating WAY, WAY, back used what we call
a "resonant reed relay", or as it was shortened to be called, a
"reed bank". Using the audio signal out of the last stage of
amplification of the receiver, this was passed through a many turn
coil, which had a Permanent magnet at its core. This created a
pulsating magnetic field at the frequency of the audio tone. The
metal frame of the unit directed this field to influence a line of
narrow, thin Swedish steel metal blades, all cut to a different
length, the length corresponding to a resonant frequency of the
audio frequencies coming through the coil. When the right
frequency came along, say, UP ELEVATOR, the metal blade
corresponding to the UP ELEVATOR direction of the ELEVATOR SERVO
would vibrate, bouncing against a contact which had a DC potential
on it. This would cause pusating DC (poor man's AC) to go across a
filter network and cause a relay (UP ELEVATOR RELAY) to close.
VOILA, the aircraft pitched it nose up, or into the ground, if you
were inverted on the deck!
Since these systems were so neat, but rather unreliable, with
controls dropping out (not useable), only the hardiest and most
masochistic persons (not to mention loaded with $ and time) kept at
it. People said they were voltage unstable, temperature unstable,
HUMIDITY UNSTABLE! The truth is that the transmitter TONES were
unstable and when BOB DUNHAM built his first REED MULTI CHANNEL
rigs, he beat this problem and true, dependable MULTI RC WAS BORN.
The story is that Bob wanted to build a rig and he looked around
for a suitable transmitter circuit. COLBY EVETT had an audio
circuit he had found in an ARRL (AMERICAN RADIO AND RELAY LEAGUE)
article (ARRL IS THE HAM'S BIBLE). It used a 3A4 audio oscillator,
stabilized with a TOROID. IT WORKED' fantastically so! For years
after this, DUNHAM'S equipment had the only reliable tone stability
to set it and forget it. I had many of his units, could tune and
set them up myself and never once had a lost command due to radio
failure; SERVO FAILURE, yes; Power Pack failure, yes; but NO
RADIO FAILURE! Dunham showed the far-reaching world his rig at the
1957 NATS, flying a TORP 35 with BRAMCO THROTTLE, BONNER SERVOS and
a BONNER SMOG HOG aircraft. Seven foot airplane at 5 1/2 pounds!
I watched him win with it and it was SMOOTH!
WALT GOOD came in second with his WAG (WALTER A. GOOD) "MULTIBUG"
flying his own radio, the TTPW (two tone pulse width or as some
called it, too tough to piddle with). It was a very critical radio
with five subminiature hard tubes and three relays, for
proportional (wriggling surfaces) of elevator and rudder and three
position escapement engine control; most axial rolls I had seen,
better than DUNHAM's AILERON ROLLS! ACE RADIO was due to kit this
radio, but most people had an ACE contracted radio man build them
for them. LOT of fiddling to make work and the servos were running
in a stalled condition continuously and the high current drain,
vibration and arcing made for fairly short servicable life. No PM
equals CRASH! All of these guys were still using pencells (AA) for
servo power. All the time you could find them changing battery
boxes, complete with cells, between flights. The LR-1 Yardney
Silvercell was just around the corner (Low Rate, 1 ampere hour,
rechargebale, vented at $6.00 per cell, 1.4-1.5 volt per cell).
Later on, when I would purchase some for Bonner Servo Power, I
found they self destructed when you crashed.
Pylon Racing (AMA, not NMPRA...remember, this is 1957) was won by
KEITH STORY of the FAST Club of California (F.A.S.T. stood for
FIRST ALL SPEED TEAM and was primarily a TEAM RACE U-Control club;
its most well-known member is probably GRANGER WILLIAMS of Williams
Brothers of Belleflower, Ca.). KEITH flew a semi-scale BONZO with
OLIVER TIGER Diesel 15 and Bonner Servos with Dunham Radio. Harold
DeBolt came in second with of all things, a smaller version of his
MULTI-BIPE, with BRAMCO REED EQUIPMENT and a FOX 15. DeBolt always
was an ENGINE MAN. He could get lots more power out of any engine
than anybody else, and ex speed man! I have slides of this contest
and DeBolt was posing with his Big Bipe and the candidates for MISS
MODEL AVIATION. Very NICE, but remember, this was 1957 and these
cuties are around 50, now!
Next time////// CITIZENSHIP gets into MULTI CONTROL; ECC/CG/Frank
Hoover also. Transistors take over. Mad scientist Herschel Toomin
doing something out in California. Johnnie Brodbeck sees need for
another engine.
|
| Sure have enjoyed this journey thus far! Yer' almost (not quite)
up to where my R/C involvement began: in the Frank Hoover F&M era.
I invite you to read through note 239, "RAMBLINGS FROM THE DESERT
RAT" for lots more nostalgia, though, admittedly, of more recent
vintage.
I tried on two occasions to make single-channel w/escapement work
with limited success and had pretty much decided that radio wasn't
a viable commodity, at least yet. After being discharged from the
Air Force, finding that I was disenchanted with U-control, I built
a Goldberg Junior Falcon, then a 1/2A Skylane controlled by Control-
laire (sp?) Mule Tx and superhet Rx built from kits, but still with
a Bonner compound-escapement. To keep the story short and to the
point, I still had only moderate success getting anything approaching
reasonable reliability from the escapement and, again, decided that,
unless things changed drastically, I could see no future for me
in R/C.
About a year an a half after my discharge, probably 1963, I ran
into a long-time U-control buddy who was flying a Senior Falcon
with an F&M 4-channel PROPORTIONAL radio. That was IT!..now a model
could at last be realistically controlled and I WAS HOOKED!! BUT,
what about the cost?...a new one of these marvels cost nearly $600!
AND...we're talking 1963 dollars here.
Then I learned that another modelling buddy, Ted White, was working
for Frank Hoover (F&M) in Albuquerque, NM and could "fix me up"
with a used set. $425 of these '63 greenbacks bought me a 4-channel
rig (only 3-ch.'s trimmable - no throttle trim) and, was I proud?!
I learned on hand-me-down Mambo's, Beams, Stormers and Falcons before
completing my first bird, a Kazmirski/Top Flite Taurus in around
'64-'65.
The F&M rig used Bonner trans-mite servo's, converted from reed-to-
proportional use, and had to be disassembled and CLEANED about every
4-5 flying sessions. To neglect this meant the feed-back pots would
gunk-up, the servo quit and adios airplane....but what a pain in
the A__! We sure take a lot for granted nowadays. Later, Frank
upgraded to the Titan Servo with frictionless inductive feedback that
eliminated the PM routine and was a giant step on the road to improved
realibility.
Before wrapping this up...did you know that F&M stood for Frank
& Mary (Hoover that is)?? Also, the F&M line of multi-channel reed sets
were dubbed C.G., not for Control Guidance as was thought by many
at the time, but for Frank & Mary's son, C.G. Hoover. I was very
close to Frank and C.G. for over 10 years 'til Frank sold out and
the business was subsequently mis-managed down the toilet. C.G.
was an expert pilot, on a very near level to Ted White and had a
devilish streak in him (see the nostalgia notes on the Albq. Fun-Fly
in note 239). He and Doug Spreng used to drive each other to the
brink of distraction with pranks like hiding the other guy's wing
just before the next round of a pattern contest...but that's another
story.........
Gotta' go, keep 'em comin,
Al Casey
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