Solved the problem but the solution will not help others.
I bought a Turnigy 9xr Pro. This uses the er9x firmware. What a difference. All of the switches now work. They were really easy to programme as well.
I have now purchased the Smartieparts programmer add on and fitted it to the 9x. The goal is to upgrade it to the er9x firmware also. So far I cannot get my laptop to recognise the programmer but I am sure it is only a driver issue.

Hello kmbcsecretary or another who may be able to help..
I have changed to helicopter but still can only get two switches to programme, gear and throttle hold. Please can you tell me which setting you used for the third.
Thanks. Peter.

Thanks. I will give it a try.
If possible, could you tell me how your 4 channel switcher works. My next project has multiple additional features to deal with. Which one is compatible with the 9x. Thanks again.

My apologies I have had another look at my radio, set the mode to Heli and this will give you your third switch. ( Not used my radio for a year due to health)

Thanks for the help. I need three switches to function. So far I have managed to get two to work using the auxiliary function. This has five possible settings, two of which are switches, the others being potentiometers. Please can you tell me which other switch is usable and how to connect it to say channel 7. I have got two circuits to work on the gear switch and the throttle cut switch. I found out about the mode setting and have change it to normal aeroplane. 🤔 Thanks.😀

hi what mode do you have the radio set ie glider /heli/prop? as it is this that sets the use of the switches, i have a 9x my self and purchased mine for the same reason as you as was using 12 channels for one of my tugs using all 8 channels plus a 4 channel switcher on the right stick.
you are best setting the mode to prop (will see plane icon on screen) to give you best use of all the switches and then you will have use of three switches as i had lights on one, radar on second and water pump on third.
hope this helps

Peter,here i put photos of simple servo switch., constructed by Petr Hajek (ufon 13).I use the same switch for switching sound modules (siren + foghorn) Channel 2 in my model ps Lulonga.
I do not know why you are not using channel 3 (throttle) to control the engine via ESC....
Regards Tom 😊

I have now connected the batteries and entered into the Aux channel mode on the TX. I have set gear to channel 5 and throttle hold to channel 6. Two of my lighting circuits now work perfectly using the gear switch and the throttle cut switch on the Tx. I just need one more to enable the third circuit to light. there are still two or three two position switches available to use but are not supported in the Aux channel menu. I am told that they can be used by altering the mix menu but I am afraid this goes beyond me at this time. Any help would be greatly appreciated.
Regards, Peter.😊

Thanks Tom.
I think I can choose between five items for each of channel 5 to 9. Two I believe, Gear and one of the others, are controlled by on/off switches on the Tx. The others are routed via potentiometers. There is, apparently, a way of changing one of these choices to be operated by a third switch using

mix

settings but I have no idea as to how.
I will try to get my LED`s working on the two switches that are available through the Turnigy rc switches I have wired to channels 5 and 6 on the receiver. I will post how I get on.😊

Hi,
As I see, there is a problem. The basic question is - what you need to control, and the other - whether this type of RC kit will allow this.
Especially .. this type is mainly designed for aircraft control. You need to choose compromises to control the ship model. This type does not allow simple switching of functions - only by means of another switching module, or by means of end switches on the modified servo. in the base allows only
proportional control of servos or ESC.
There are RC sets, that have switching functions, such as Graupner - e.g. Graupner mc-20 12-Channel HoTT
but these are far more expensive...
The basic wiring is the 3rd throttle for engine control (ESC), channel 4 for control of the rudder.
there is a possibility to use channels 1 and 2 for switching the added end switches but it is not possible to switch them permanently (perhaps with the help of the added relay)-.
channel 5 can be used - setting> AUX> GYR> PIT TRIM - (rotary potentiometer control.) similarly
channel # 7. AUX settings> HOV THRO
Channel No 8 - AUX Settings> HOV PIT
Operate again using rotary potentiometers - see function descriptions.
These channels again allow only proportional control.
Switching can be done (maybe) using channel # 6
settings >AUX>FLP> Gear ON/OFF (I did not try this)
It is good to get familiar with the setting of the individual elements and check this on the display for the test (without the connection of the receiver !!) before you all plug in the model.
I hope it helped you a little bit..

Tom