Vernon Tolson Posted January 23, 2016 Share Posted January 23, 2016 I am in the process of resurrecting a FVK ASW24 slope soarer with a old Multiplex Cockpit set up. As I want to teach my sons as well, I have researched a bit and got a multiplex lead 85122 and an old Pico-line transmitter. Apparently this is the only set up which will allow the Cockpit transmitter to be the Teacher, and the 85122 lead is the only one I should use in order to connect it to a Pico-Line as the Student. The basic description of the 85122 lead is : "Connecting lead for MULTIPLEX PiCOline and COCKPIT MM transmitters for Trainer mode (teacher / pupil) operations. The lead is connected to the MULTIPLEX multi-function sockets (charge sockets) which are fitted as standard. The control functions are transferred by operating the ON/OFF switch on the Trainer transmitter, i.e. a separate switch for transferring the control functions is not required. The basic requirement for Trainer mode operations with this lead is that both transmitters must be capable of controlling the model independently, i.e. both transmitters must be on the same frequency band, operating on the same channel. All other settings (servo and mixer values, trims, ...) must also be identical." I also read somewhere that when you switch off the Cockpit and the Pico-Line is activated, then the Pico-Line takes its power from the Cockpit battery. Apparently the Pico-Line LED might/will glow red when in this mode. The Multiplex Cockpit is all set up and the glider ready for its maiden flight. The Pico-line came with no battery or crystal. When I connect the two transmitters with the 85122 lead, there is no red light on the Pico-Line. Maybe a bit of a long-shot but has anyone used this set up (or understands how it works) who can advise whether a red light should show at this point ? I don't think I need a separate battery for the Pico-line (or do I?!) and I haven't got round to getting the extra matching crystal for the Pico-Line until I'm confident I'm at least heading in the right direction and getting some power on the student transmitter..... Quote Link to comment Share on other sites More sharing options...
Former Member Posted January 23, 2016 Share Posted January 23, 2016 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
Vernon Tolson Posted January 23, 2016 Author Share Posted January 23, 2016 Appreciate your reply Percy. From what I understand, the Cockpit only has a Student mode. As it is my main set, it led me down a path of seeing if there was a way to make it the Teacher set. I found some old material online about the 85122 lead and using it with the Pico-line. Unfortunately it is old archived material on the web mainly in German !! The information seems reliable and the advice originally came from Multiplex at the time. I think the 85122 lead is not the same as the standard buddy lead and was made specifically for the purpose of using the Cockpit as the teacher and the more entry level Pico-Line as the student. Unfortunately I can't find much about anyone actually setting it up or using it themselves I think completing the Pico-line with a battery and then a crystal is worth a shot. Then I've done all I can to get it going!! If anyone can talk me me out of pursuing the set up because it is flawed before further expenses - please let me know! Quote Link to comment Share on other sites More sharing options...
Former Member Posted January 23, 2016 Share Posted January 23, 2016 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
Frank Skilbeck Posted January 24, 2016 Share Posted January 24, 2016 you could also try Mike Ridley at modelradioworkshop.co.uk Quote Link to comment Share on other sites More sharing options...
Former Member Posted January 24, 2016 Share Posted January 24, 2016 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
Frank Skilbeck Posted January 24, 2016 Share Posted January 24, 2016 Re-reading this thread, these are quite old transmitters and it sounds like the buddy box set up is very much like the old Digifleet set up, where you had to have both Tx's on the same frequency and same set up, using the on/switch on the master Tx to ON switched off the trainer Tx and switching the master Tx off switched on the pupil Tx. So yes both Tx's needed to be powered and be on the same frequency. Quote Link to comment Share on other sites More sharing options...
Former Member Posted January 24, 2016 Share Posted January 24, 2016 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
Max Z Posted January 24, 2016 Share Posted January 24, 2016 I found this thread (in German) describing the system. It is not really mysterious, basically it is like Vernon described it in the opening post. Both the trainer and student Tx's must have full transmitting capability to control the training airplane, i.e. set up with the same frequency crystals, and be trimmed to control the model in exactly the same way. Apparently there is no possibility for transmission of the PPM signal over the buddy box cable, as is usual for more modern systems. The Multiplex transmitters have a general purpose, 5-pin DIN connection, with pin 2 assigned to external power. A feature of the Multiplex Tx's that I know is that the on-off switch will transfer power from internal power (on) to feeding external devices (off). Additionally, in the on position the charging pin is disconnected. The way I understand this particular cable works is as follows: - when the trainer Tx is switched on, the external power pin is disconnected - when the trainer Tx is switched off, the trainer Tx battery is connected to the external power pin, which transfers the power through the buddy box cable to the student Tx charging connection, and it will start to transmit. - the student Tx (the Pico-Line) does not need to have its own battery, as it is powered by the trainer Tx. - the student Tx shall be switched off, otherwise the charging pin will be disconnected. There is some stuff in the German site that I don't quite understand (and I don't mean the words), about using the MM as the student Tx, in which case it does need it's own battery, even though it remains switched off. But since you don't intend to use it that way, it is not important. Note that the cable plugs are marked "Lehrer"(Trainer) and "Schüler"(Student). I'd say all it needs is a good test before you take off! Max. Edit: pin functions revised, I got it wrong the first time (always helps to get the documentation out....) Edited By Max Z on 24/01/2016 11:03:33 Quote Link to comment Share on other sites More sharing options...
Former Member Posted January 24, 2016 Share Posted January 24, 2016 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
Max Z Posted January 24, 2016 Share Posted January 24, 2016 What is the worst that could happen? Admitted, you have two Tx's operating on the same frequency, but they are operated from one power source with one switch controlling both. As long as you leave the student battery-less, there is no risk of him accidentally switching on and transmitting on the same frequency. All he will achieve is that he cuts his own control of the airplane, and it will be the task of the trainer to retake control (but that is his task anyway). Max. Edited By Max Z on 24/01/2016 11:18:06 Quote Link to comment Share on other sites More sharing options...
Former Member Posted January 24, 2016 Share Posted January 24, 2016 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
Vernon Tolson Posted January 24, 2016 Author Share Posted January 24, 2016 Appreciate your feedback and comments on this. I had a good read of the link you included Max so thanks for that. My set up might not be the best solution but I will give it a good test !! Keen to get the kids outside more and with the Peak District on our doorstep, I want to try and get something set up where they feel involved. My original post came about because I got the Pico-line TX off ebay and sourced the 85122 lead from a model shop in Germany. When I connected it up, I expected the Pico-Line to shows signs of life taking power from the Cockpit battery. With no signs of life (like a red LED light or anything), then I'm wondering what else I need to get it going. Either just an extra TX crystal or both a battery and TX crystal. Or if I have sourced either a faulty lead or a faulty TX. I think I will give the extra TX crystal a go and keep my fingers crossed!! I will hold fire on the Pico-line battery as the link suggests it should work without one. Then actually Frank's post makes sense and that suggests I will need a TX battery. I will go off and think it all through as it may be worth getting a battery for the Pico-line anyway. Thanks again and I will post an update.... Edited By Vernon Tolson on 24/01/2016 11:45:15 Edited By Vernon Tolson on 24/01/2016 11:54:57 Quote Link to comment Share on other sites More sharing options...
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