danvel

I've built the interface cable between my FUTABA FF6 and the PARALELL printer PORT to play FMS.
I've conected pins 4 & 5 but the radio doesn't power up when I plug the cord in so I must turn it on from the main switch in order to get the pulse train trough the cable.
How can I use FMS without emmitting radio power and draining the radio's batteries???
Does anyone have this problem???
Thanks a lot, this forum is great!
Greetings to everyone from SPAIN.

jh

sorry you need the radio on to work unless you want to start hacking away in side your box which will be mess'e

danvel

I thought that it was possible to power the decoder (but not the emitter) of the radio by means of one of the pins in the trainer conector. Perhaps in other radios, not in FF6?
Thanks anyway. I've been to Manchester a couple of times and I've always found nice people there!

Wright Flyer

When I use FF6 with FMS I trun it on but remove the Tx crystal which ensures that it won't radiate RF or use huge amounts of battery power.

Cliff

danvel

Thank you, Cliff. That's a great idea. I suppose we can't damage the unit doing that... do we?
I'll try right now.

danvel

For those interested:
Power consumption with crystal installed is about 150 mA.
Power consumption without crystal is about 40mA.
So the batteries last 3 times longer if you remove the crystal from your radio and you can collapse your aerial without the problem of overheating the RF transistors.

KB9STD

My Feedback: (1)

danvel,I believe that you re correct in connesting pins 4+5 to cancel rf emission.However,as the function is intended for "Buddy Box" operation it utilizes an external power source(it gets it's power from the instructor's radio via the buddy cord).I think the system would word if you were to supply 9.6 volts or thereabout through the interface cord.

JoeAirPort

My Feedback: (41)

How hard is it to take out the crystal?

cubanflyer

If you do not remove the crystal, you also stand a good chance of damaging the RF unit.

hooleydog

My Feedback: (24)

HEH HEH, I'm using a 9 volt regulated ac adapter connected to pin 1 on the plug that goes into the buddy box connecter (from the pic serial interface). because 9 volts is going into pin 1, I don't have to turn on my transmitter to use FMS or R/C Plane Master. All I did was to add another 2 core cable into the Futaba 6 pin plug, and it goes to the adapter. Also pin 4 and 5 in my plug are shorted.

bz1mcr

Hooleydog,
Thanks for the information on modifying a PIC cable for FMS to allow operation without using the transmitter battery or powering the RF section. Where did you learn about this modification, or how did you decide this was the way to do it? I would like to do just what you did, but I need to confirm where you connected the +9v and ground from the AC adapter. As I look at the plug connected to the PIC cable I see a center pin and pins at 2,4,6,8,& 10 o'clock. I see no numbers on the plug or transmitter socket. How are the pins numbered?

As I understand your post the +9V goes to pin 1 (Is that the pin at 2 o'clock looking at the plug on the PIC adapter?) Where does the AC adapter ground wire go? (center pin? case? or one of the other outer pins?)

Finally, will I need to connect pins 4&5 together if they are not already? I purchased the PIC cable and have not looked inside yet.

KB9STD

My Feedback: (1)

Contact pin configuration viewed on female plug mating face :
1 = +V batteries (SWITCHED)
Shield = GROUND
2 = OUT
3 = IN
4 = +V (for some transmitters only). Connecting pin 4 and 5 to each other on some transmitters will stop the HF-transmission and thus the transmiiter will not send out any signal (this is the case for 9ZAP/9ZHP, probably also for the FF8/8UAP and FF7/7UAP, NOT for the Robbe/Futaba F16-FC16-FC18, for the FC28 I don't know)
6 = +5v on certain transmitters only (9ZAP/9ZHP, probably FF8/8UAP and FF7/7UAP) and is used by DSC-cable.

bz1mcr

KB9STD,
Thanks for the information, but I still need help.
Sounds like you are talking about looking at the female socket on the transmitter. Is that right?
and you did not indicate how the pins are numbered, clockwise from the top? That would make the 2 O'clock socket hole #1 and that would mate with the plug pin at 10 O'clock when looking in the end of the plug, right?

Hooleydog,
Please confirm. Did you connect the ACadapter's +9 V lead to the pin at ten o'clock looking at the pin end of the plug, and the ground lead to the shield?

BTY, I have a Tower System 3000 transmitter, I think the trainer cord setup is the same as Futaba's 4 channel radios.

hooleydog

My Feedback: (24)

bz1mcr ,


Futaba Contact pin configuration viewed from behind the male plug(solder side), clockwise (notch at the top) 1, 2, 3, 4, 5, middle 6 (6 not connected) 9 volts regulated to pin 1, and ground to the shield. Also Pins 4 and 5 must be shorted too.... I know cos I'm using a a/c adapter connected to my transmitter

KB9STD

My Feedback: (1)

bz1mcr,
Looking at the plug from the solder side(where you connect the wires),the pins are numbered clockwise-begining next to the notch.This would be the same as looking into the socket of the radio.Looking at the socket,find the notch and pin 1 is the first pin clockwise from it.

"I think I have that correct.Please,someome correct me if I'm wrong!!!"

I would advise that you use a voltmeter to double check.The correct pin (at the socket) should have around +9 volts between it and the outside of the socket(ground),when the radio is switched on.

Note:You WILL have to connect pins 4+5 together(just put a short wire across them,or you can make a solder "bridge").Without the pins connected,the radio WILL transmit an rf signal when the external power is applied.

bz1mcr

Thanks for the great information and the explanation of the pin numbering. I am on my way to make the modification now. I'll report back after I try it out.

I have only used the FMS adapter twice and I used it with the crystal in and the antenna collapsed. Thats what the instructions that came with it said to do. Besides being time limited by the battery, I noticed a smell coming from the transmitter. A hot/over heated electronics smell. It survived but I don't like using it like that. The external power supply and connecting pins 4and 5 to shutdown the RF section seems like the way to do it right.

bz1mcr

I'm up and flying. Thanks to the information in the last few posts.

4*60

My Feedback: (41)

Or use a radio with an RF module and remove it. You can then use FMS for hours and hours.

KB9STD

My Feedback: (1)

Really glad it worked out for for you,and glad we could help.Yes,using an external power source and disabling the rf output via pins 4+5 is the right way to do it.Pulling the crystal will work(and it's foolproof).But why stress the fragile crystal and it's socket again and again when the manufacturer has put in a system for just that purpose?Using a radio with a removable module works too,But not all radios include the feature.