galloping ghost circuit

[brucej]

hi all
i am looking for a circuit of a very old r/c system
called galloping ghost
has anybody got a copy in an old magazine that they may be able
to scan for me please
any help appreciated
thanks brucej

[Sparky Paul]

The fun I had with Galloping Ghost...
All it requires is a variable pulse width and rate circuit, running a Mighty Midget motor.
I'm afraid the rules demand the MM, anything else and the authenticity police will come a'knockin'.. :)
A couple 555 timers and pots should do it.

[BMatthews]

If you are trying to fix an old system a brand name and model would be helpful. If you're trying to build up a new system to relive the old days then some info on what you have so far would help.

[Mr.RC-CAM]

Attached is the GG circuit from the Sep-Oct 1966 Grid Leaks Magazine (a wonderful magazine in its day). This article was authored by Don Baisden. World Engines sold this pulser add-on as a kit for $14.98 (about $85 in 2003 dollars) and it was very popular.

The area in yellow is the RF modulation circuit of a Controlaire Mule Tx. Just sub your Tx in its place.

The 75K pot selects pulse rate for the elevator. The 10K pot is for rudder duty cycle. The N.C. and N.O. switches are for throttle control (silent carrier or solid tone). Other than the UJT, the parts are not critical.

[Mr.RC-CAM]

The board layout:

[Mr.RC-CAM]

The PCB foil pattern:

[brucej]

to mr rc-cam thank you very much for posting the gg pulser
cct, very much appreciated
by any chance would you have the receiver circuit ?
thanks
cheers brucej

[Mr.RC-CAM]

With a GG system there is no decoder in the Rx. The output stage is buffered (via transistor or relay) in bridge fashion and connected to the actuator. Rudder, elevator, and throttle is mechanically "decoded" using spring biased levers and wheels.

Some of the easiest methods used a Rand or Controlaire GG actuator (popular devices in the 1960's-1970's). Or, tough it out and use the good old Mighty Midget motor like Sparky Paul suggested. The Mighty Midget was another popular component in the old days (I recall it first appeared sometime in the 1950's). I was never thrilled by them and much preferred the Rand Actuator (very easy to use).

For extensive help with GG you should visit the Vintage Radio Control Group at http://groups.yahoo.com/group/VRCS/

RC-CAM

[brucej]

to mr rc-cam, thanks for the reply
yes i understand about the mechanical "decoder"
what i was trying to ask about was do you still
have the actual receiver schematic
that drives the relay or actuator ?
i am very interested in that part of the system
i have joined the vrcs group, thanks for that
brucej

[Mr.RC-CAM]

If you are looking for an old 27Mhz design then the folks at VRCS should be able to help out.

RC-CAM

[Bob Chiang]

Here are scans of an article to build an albin receiver. It was the micro system of its time.

-Bob Chiang
Ithaca, NY USA
(still have an EK pulse system with dual Rand actuators)

[Bob Chiang]

pg 2

[Bob Chiang]

pg 3

[Bob Chiang]

pg 4

[Bob Chiang]

pg 5

[Bob Chiang]

last pg

[brucej]

to bob chiang
thank you very much for posting the scans of the GG system
i appreciate the time you spent doing this
it is a great help
cheers brucej

[brucej]

to bob chiang
bob did you ever build the Albin kit ?
brucej

[Bob Chiang]

Hi Bruce,

No, I never built the Albin though I dreamed of it and its associated Bentert actuator. I did build a Controllaire single channel receiver kit and installed it with an escapement into a model, but I never flew with that system.

On the subject of galloping ghost and mechanical "decoders", there was an alternate system to the torque rod and wire loops usually used. Picture a rudder hinge line that is slanted out at the top. It will provide some up elevator force as it swings to the sides. When the pulse rate is slow, the rudder spends relatively more time out to the sides and provides relatively more up elevator.

And before there were electronic pulse "encoders" for the transmitter, people made mechanical ones. One system used a rotating cylinder with a wedge shaped conductor around the circumference and a wiper contact connected to the transmit function. When the wiper was moved to one side, it would contact the wide part of the wedge and transmit a longer pulse, when moved to the narrow part of the wedge it would transmit a shorter pulse. Vary the speed of the cylinder rotation to change the pulse rate.

Clever stuff eh?

[brucej]

hey bob thats a smart idea about the wedge "encoder" i have seen a sorta same thing for sending morse code.
on monday one of our indoor flyers was flying a receiver with a albin frontend and opamp driver for the coil. flys very good
brucej

[brucej]

i have bulit some of the pulser cct, getting a nice saw tooth pulse from the UJT i used a 2n2646
funny thing though, the pulse slows down to a stop with only 15k ohms, that leaves a lot of pot travel left useing a 75 kohm pot
brucej

[Dave Wulff]

Bob,
Thanks for posting this article. With the help of Fritz, I built several of these, along with some crude BIRA type actuators. It was in the early 90's, pre internet, and getting information was tough and slow. What a difference now.
Dave

[jfmthor]

Excelent Post !!!

congratulations!!!


Thanks

[jfmthor]

hello all

is proportional old east radio system control?

Thanks

J.F.

[brucej]

for those interested i have made an albin receiver based on the modern deseign and it works extremely well for the minmum number of parts that is in it
brucej

[Mr.RC-CAM]

How about posting photos of the finished device and a schematic?

RC-CAM

[brucej]

ok let me work on it
brucej

[Juanjo]

I am working very hard building a GG system.
It is a debt that I have with myself from the 70's.
I used old Ace schematics and everything is working fine.
At this time I am building the Tx final version, designing a new pc for the Rx, beause the test one was very large and I am cleaning the servo design.
I used a lot of time (money too) but now I am very happy.
The next step is to build a old time sailplane and try everything together.
I used the Albin receiver schematic, a servo and a servo switcher schematic from R/C Modeler Magazine, the Wee Tx schematic and the pulser schematic from Ace.
I tried a lot of transistors, coils and circuits and I will be very happy to help to the people who want to recreate this experience.
I have got a solid conection in the ground, in the downtown, of about 200 meters, about 700 foots.
That is enought to me.

[brucej]

juanjo
well done on your GG project, 200 meters is good.
its a lot of fun playing with the old circuits, keep up the good work
brucej

[vintage1]

Be careful: That Albion receiver is NOT very temperature stable..I built one using that arrangement of biassing the audio stage years ago, and its a BIT dodgy..you need to select the base bias resistor to suit the actual transistor..and hope the temperatire stays more ore less what it was when you slected it.

[Juanjo]

Thank you for your advice.
When I use the old Ace Albin Schematic, I tried with a potenciometer to find the best resistor value.
Then I used the values of a new schematic, that I could find in this forum, I tried the BC108c as osclilator, and everything began to work. Is very important to match the audio tones of the Tx and the Rx. This make the difference.

[brucej]

juanjo
you say you used a servo switcher schematic from R/C Modeler Magazine, and the Wee Tx schematic .
If possible could you please post the circuits here, i would be very interested in them thanks
and what frequency was the audio tone you used ?
brucej

[Juanjo]

Here are the switcher and wee schematics.
In the switcher I use the bc328 and the bc 338, r1 was 150 ohms and I replaced the 32mf6v by a 3,3volt 1/2 watt zenner diode.
The coils in the Tx werw the Digital commander coils from Ace. If you want I can give more information about that.
The Albin that I built works about 500/700 cycles, so I changed the 22k resistors in the Wee multivibrator section by 33k.

[brucej]

juanjo

Thank you very much for posting the circuits, i collect old circuits.
the wee TX circuit is nice and simple, and should be easy to make.
interesting that it works best at 500/700 cycles, i should be able to make the coils ok.
thanks
brucej

[Juanjo]

I used 3 mps6531 in the wee rf section and now I will try with a bc108c in oscilator section because it has a very high hfe.

[vintage1]

The best S/C tone TX I built used a single BFY51 (TO5 can) as RF output decvice, and on 18v with NO emitter resistor pulled a nice sort of 250mA out of the batteries..4.5W input and about 4W out judging by the heat of the BFY....

That was on 27MHz..the BFY was a HF transistor rated at aboutr 70Mhz I think.

Yes, we were legally limited to 1.5W in those days..the average OS pixie put out about 100mW. My transmitter could control any superregen on the field, and up to a couple of miles off it.

Never had any interference problems at all.

[Juanjo]

Do you think the BFY51 will improve the Wee RF amplifier section?

[vintage1]

Do you think the BFY51 will improve the Wee RF amplifier section?

There are probably better ones these days..any NPN RF power transistor in a good TO5 can with a clip on heatsink will net you a bit more power..you can vary the size of the emitter resistor(s) to get more current, up to the the point at which the transistor gets too hot or you go to illegal power levels.

[Juanjo]

Thank you very much.
I will try the orginal MPS6531 with other emitter resistor and I will let know you what happened.

[brucej]

juanjo
in your switcher what battery voltage did you use for the centre tap batteries
brucej

[Juanjo]

I use 4,8v center tapped.
By the way, do know about some kind of GG deco to use 2 actuators?
I have the Lathi schematics, but I did not have luck with it.
I belive that Rand have one but as a comercial item the schematics are hard to find.
I read in this forum about a book "Low cost proportional", but it seems to be losen in the time.

[brucej]

hi Juanjo
thanks for reply, so you use 4.8 volts, so two nicads 2.4 volts each side.

"some kind of GG deco to use 2 actuators" do you mean like one actuator for rudder and one for elevater, ?

i have seen circuits that do this , they use a pulse "rate"detector that goes across the relay and operates another "motor or actuator", i can scan a circuit to see if that is what you need.

"Low cost proportional" i dont know this book but will look out for it
brucej

[Juanjo]

Hellow Bruce,
Yes, I was talking about one actuator for rudder and one for elevator.
I would like to use it with the Albin relayless receiver.
I made an actuator with a Futaba 1/4 scale motor servo and with the mechanical decoding it can drive rudder and servo, but I would like to use two actuators, based in smaller servo motors.
I think that the book is an English book, and I found one of it (web) in a used book store in England, bit it was solded.

[brucej]

so you mean something like this ?
i hope this picture is attached ok
its big

brucej

[brucej]

if you cannot read the values let me know and i will email you a hires pic
brucej

[Juanjo]

Thank you Bruce
It seems like the one I wsa looking for.
I will check it as soon as possible.
Thank you very much again
juanjo