View Full Version : Run 2 Frequencies on 1 std. controller!

02-10-2003, 09:12 PM
Okay, I have a 27, 49, and 57mhz cars. I am tired of hauling around so many controllers, and I don't wanna buy a multi (which doesn't accomodate all of these frequencies anyway.

Here's my solution... Run as many frequency crystals on 1 contoller as you want with a switch to select between them. You could run all of the frezuencies out there if you get the right switches.

02-10-2003, 09:16 PM
man dude thats one of the best mods ive ever seen thats dope dude

02-10-2003, 09:35 PM
dude thats sweet but what would be cooler id witha bit char-g booster car is to do that mod on it except with all four freq. and then buy the booster machine sets and you can use wich one when you want

02-10-2003, 09:48 PM
Yeah, but I don't have enough room right now in my booster controller because I installed my alternate booster button mod on it. Check it out in the mods forum. I agree, though. It's totally possible and if you got a multi controller, and added the american frequencies, then you'd have everything plus the booster fctn.


02-11-2003, 06:10 PM
that is awsome man!

02-12-2003, 09:19 PM
Great mod!
Two thumbs up, way up!

02-13-2003, 09:07 PM
With the proper rotary switch and the right crystals, you could do all available frequencies!
(I don't know how small it would be though)

Again, really great mod.

02-14-2003, 12:43 AM
You should just use two crystal sockets, one for the car and one on the controller.

03-10-2003, 08:43 PM
Can you use two freq's at once by soldering the crystals in parallel? I know it would only limit the number of people I could race. I broke my controller, but I have the crystal.

03-11-2003, 08:48 AM
Excellent mod chelboed!

Just wanna clear up a few things though.

BillyP: you can't solder them in parallel, it just won't work. I think the low freq crystal will cancel out the higher freq one.

Nathan: the car isn't crystal controlled, but based on what is called a tuned circuit. This is determined buy R, L & C values in teh receiver stage of the circuit.

In fact I'm trying to design a new receiver circuit that can have multiple freq's.

Check it out
here (http://www.ausmicro.com/topic.asp?TOPIC_ID=254&FORUM_ID=9&CAT_ID=2&Topic_Title=RF+mod+%2D+more+controller+channels&Forum_Title=BCG+%2D+Technical) at ausmicro.com


03-12-2003, 04:16 AM
Is it possible to get those crystals somewhere? Rather than to just pull them from another controller?

It would be great to not have to buy whole controllers just to have other frequencies!

Also, I had a question, perhaps one could install a switch to reverse the forward/backward controll so that you could drive both zips and bits with them?

any input on that would be great!

03-13-2003, 03:03 AM
Your LHS should have the crystals.

And it would probably be possible to wire in a switch that inverts your forward and backward control. If I wasn't tired I'd start trying to figure it out now

03-13-2003, 01:55 PM
local hardware store?

03-13-2003, 02:55 PM
LHS = Local Hobby Shop


03-13-2003, 03:17 PM
You can get all the electronic stuff you'll ever need (almost) at this (www.allelectronics.com) site, hence the name, All Electronics.

03-13-2003, 05:40 PM
thanks payaso and billyp

03-13-2003, 05:45 PM
It's about time this thread goes where it belongs...

03-13-2003, 05:56 PM
can someone give me a quick overview.

I'm sitting here trying to figure this out, and I can't remember for the life of me...


(or is Joules power?)
Watts is power, right?
Amps is current?
What's Volts?
and the conversions for each?

(I used to remember all this from Physics, but my brain is shot!)
(also this is really sad, considering i'm studying to be an engineer)
(but don't cringe yet, i'm only in the first year, i've yet to take an engineering class!) hehe.

03-13-2003, 07:36 PM
Watts is Power, SI (Standard Index) is W.
Voltage is potentail difference, SI is V.
Amps is current across this difference.
Resistance is measured is Ohms.

Power = Voltage * Current

P = V * I
P = I^2 * R
P = V^2 / R

(I^2 = I * I, or I squared)

Voltage = Current * Resistance

V = I * R
I = V / R
R = V / I

If only this forum had an equation editor, *sigh* :p


03-13-2003, 08:14 PM
thanks so much~

lol, I could only remeber a VIR thing from school... but i rememberd it wrong (MVP mass, velocity, and potential) and made it a VIP... Voltage, amps, and Potential and it confused the crap out of me~!

(that's the kind of guy i am... a few frenchfries short of a happy meal you might say)

Thank you so much!

03-13-2003, 08:20 PM
could you also help me with a few things?

I know that if you have two batteries, you add the voltage.

ie. 1.5V battery in series with another 1.5V gives 3V
(end to end)

How does it work if you wire them in parallel? does that keep the voltage, and effect the amperage?

and is resistance done the same way?

could someone give me the basics? or at least point me somewhere that I can find the basics? (the sad thing is I used to know all this, now it's just a big jumble of uncertainties.)

Like if you wire two 4 ohm resistors in series you get 2 ohms...and if you wire two 4 ohm resistors in parallel you get an 8 ohm resistance right? (or is that backwards?)

I want to say series you add, parallel you divide for resistance?

i can't wait for my basic circuits class next semester

*very frustrated*:(

03-14-2003, 10:28 AM
Batteries in Series = Add the Voltages
Batteries in Parallel = Add the Amperage

Resistance in Series = Add the Ohms
Resistance in Parallel = Multiply all the ohms, then divide that number by the sum of all the ohms (aka "Product over the Sum")

03-14-2003, 05:04 PM
...and you can only use that formula for two resistors at a time. If there's more than two (in parallel), you have to add the recipricals:

1/a + 1/b +1/c ... = 1/R

04-07-2003, 12:47 AM
I have a 49 Mhz transmitter will a busted forward switch -- it's permanently pressed in. Anyway, so I thought that I would try this mod with my 27 Mhz controller. Now I have the center poles of a DPDT switch attached to the PCB of the controller where the crystal was, the 27 Mhz crystal attached to the right poles, and the 49 Mhz crystal attached to the left poles:

|============27 Mhz
|===============49 Mhz

When I throw the switch to the right, it drives the 27 Mhz cars, but when I throw it to the left, it will only drive the 49Mhz cars if they are right next to the controller and upside down (no wheel resistance). The left and right turning seems to work, but the motor sputters.

I took the 49 Mhz crystal out and put it in a Motor Works controller that I had that no longer had a crystal. I had to mod the PCB on that controller to switch the forward and reverse, but the controller will drive my 49 Mhz Microsizer. Is it possible that a 27 Mhz controller has something else filtering the frequency besides the crystal?

04-08-2003, 04:05 PM
I have an extra 27mhz crystal. Anybody want to trade for it?

04-15-2003, 12:38 AM
Here's a schematic, kinda...

04-15-2003, 09:36 AM
I had a DPDT switch, so the center poles both go to the transmitter board and each side of the switch has a crystal attached to it's two poles ( again refer to text graphics :D ), but it's essentially the same. Still doesn't work though -- I must have a short. People have been telling me that there is nothing wrong with how I wired it, so it's time to get out the meter and check the leads. Just haven't had a chance yet.

08-03-2003, 10:41 PM
What if u did that to the car so u only need 1 remote for multiple cars. Think of the combanations if u had two cars with switches and 2 remotes withthe switch!

49 remote/ 2 49 cars
27 remote/ 2 27 cars
49 + 27 remote/ 1 of each (SP)
1 alternating remote/ 1 of each
and so on

That would be perfect for riggin a race, take control of the other car for a second! Lol ;)

09-24-2003, 03:44 AM
Do the crystals have + and - sides? If so, how can you tell?

02-25-2004, 09:33 AM
Originally posted by Madcat
Do the crystals have + and - sides? If so, how can you tell?

No they don`t...