Juhunio 6830 Posted September 5, 2020 I'm restoring and rebuilding a 58211 Mini Cooper that came with a Tamiya MSC and two Acoms servos. No radio gear. Ideally I would like to keep the MSC and twin servos, but use it with my regular radio gear (basic Absima stick radio and receivers) Both servos have regular 3 pin plugs so they fit fine, but the MSC switch has a two-pin plug where the receiver only has 3 pin sockets. Does anyone know if there is an adapter to enable the two-pin MSC switch to fit a 3 pin receiver socket? Or, seeing as the whole MSC switch cable is detachable, a replacement switch that can be plugged into the 2-pin connector from the MSC, and into the 3 pin socket on the receiver? Or are these two worlds completely incompatible? Cheers! Share this post Link to post Share on other sites
Fuijo 880 Posted September 5, 2020 I'm pretty sure you just plug it into the receiver as it is, making sure the red and black wires are lined up with the red and black wires from the servo plugs. Black and red are positive and negative, and the yellow wire is the signal wire which you don't need for an MSC. Hence only a 2-pin plug is required. 2 1 Share this post Link to post Share on other sites
Juhunio 6830 Posted September 5, 2020 11 minutes ago, Fuijo said: I'm pretty sure you just plug it into the receiver as it is, making sure the red and black wires are lined up with the red and black wires from the servo plugs. Black and red are positive and negative, and the yellow wire is the signal wire which you don't need for an MSC. Hence only a 2-pin plug is required. That sounds ridiculously straightforward! I'll give it a go, thanks! 1 Share this post Link to post Share on other sites
Juhunio 6830 Posted September 7, 2020 Update; that didn't work! Initially plugged the MSC into CH3 on the receiver, and the servos into CHs 1 and 2. Only 1 servo would ever work, the one in CH2. Both servos worked, but never at the same time. So I moved the MSC to CH1, put the servos in CH2 and Ch3, and there was a crackle, a puff of grey smoke and a terrible smell. The receiver fried, the back of it melted a bit Ooops! Can anyone help me out, what am I doing wrong? Or is it simply a case of incompatible technologies from different eras? Share this post Link to post Share on other sites
catman79 346 Posted September 7, 2020 did you make sure the red wire went to positive and black to negative? Share this post Link to post Share on other sites
Juhunio 6830 Posted September 7, 2020 4 minutes ago, catman79 said: did you make sure the red wire went to positive and black to negative? Yup, lined the wire colours up with the wires on the servo plugs, which were fitted the right way round There's no BEC on the receiver...not that I fully understand what that is, but is that an issue?? Share this post Link to post Share on other sites
catman79 346 Posted September 7, 2020 unfortunatley i'm no expert either, i think bec means battery eliminator circuit, from memory if the receiver doesn't have this built in it wont work, my guess would be that modern receivers don't have this built in as i'm guessing the esc's probably have it instead. however this is from the late 80's so my memory is a tad hazy! 1 Share this post Link to post Share on other sites
martinjpayne 273 Posted September 7, 2020 Yes, the BEC reduces the voltage from the main battery pack to 6V (to replicate a 4 AA cell Rx battery from the old days). The fact is your receiver states 4.8-6.6V on the label, and you just plugged in 7.2V from the MSC! 1 Share this post Link to post Share on other sites
martinjpayne 273 Posted September 7, 2020 You need to fit an external BEC between the MSC and the Receiver: https://www.ebay.co.uk/itm/Hobbywing-3A-UBEC-5V-6V-Switch-Mode-BEC/221655594331?hash=item339bb3f55b:g:EyUAAOSw6j9esBP4 Share this post Link to post Share on other sites
Juhunio 6830 Posted September 7, 2020 51 minutes ago, catman79 said: unfortunatley i'm no expert either, i think bec means battery eliminator circuit, from memory if the receiver doesn't have this built in it wont work, my guess would be that modern receivers don't have this built in as i'm guessing the esc's probably have it instead. however this is from the late 80's so my memory is a tad hazy! Yes, that was as far as my post-fry logic took me, BEC is now in the ESC so the receiver probably wasn't up to it! Share this post Link to post Share on other sites
Juhunio 6830 Posted September 7, 2020 18 minutes ago, martinjpayne said: Yes, the BEC reduces the voltage from the main battery pack to 6V (to replicate a 4 AA cell Rx battery from the old days). The fact is your receiver states 4.8-6.6V on the label, and you just plugged in 7.2V from the MSC! That makes sense! Do any 'modern' receivers have built-in BEC, or is it a case of use the adapter you shared above, or find an olde-worlde radio / receiver set? Share this post Link to post Share on other sites
martinjpayne 273 Posted September 7, 2020 2 hours ago, Juhunio said: That makes sense! Do any 'modern' receivers have built-in BEC, or is it a case of use the adapter you shared above, or find an olde-worlde radio / receiver set? Some do have built in BEC, usually the more pro kit (expensive) ones though: Futaba 'HV', Sanwa, Graupner (which I use). For more reasonably priced kit look at the Turnigy GT5... also look for 4.8-7.4V (eg. Absima R4WP) or BEC on the front. Best really to research the specs of the Rx before buying new kit. 1 Share this post Link to post Share on other sites
Juhunio 6830 Posted September 7, 2020 36 minutes ago, martinjpayne said: Some do have built in BEC, usually the more pro kit (expensive) ones though: Futaba 'HV', Sanwa, Graupner (which I use). For more reasonably priced kit look at the Turnigy GT5... also look for 4.8-7.4V (eg. Absima R4WP) or BEC on the front. Best really to research the specs of the Rx before buying new kit. Ah, Ok, so if the receiver says 4.8-7.4V on it (or at least a higher value that is >7.2V), then it should take this plug from the MSC without frying? Sorry if these questions seem obvious, this is all new to me! Share this post Link to post Share on other sites
martinjpayne 273 Posted September 7, 2020 1 hour ago, Juhunio said: Ah, Ok, so if the receiver says 4.8-7.4V on it (or at least a higher value that is >7.2V), then it should take this plug from the MSC without frying? Sorry if these questions seem obvious, this is all new to me! Yes, providing you don't go to 3S batteries. I guess you're using 7.2V Nimh stick packs as you sound old skool. 😆 Still, it probably would be cheaper in the long run to use the BEC module (tucked out of site) as it's only one car you're renovating to original condition, rather than change to new radio kit. Be aware the Absima R4WP Rx is A.F.H.D.S.2 not A.F.H.D.S. like the R3FS Rx you use: your Tx may not be compatible. Share this post Link to post Share on other sites
martinjpayne 273 Posted September 7, 2020 PM'd you. Share this post Link to post Share on other sites
Fuijo 880 Posted September 14, 2020 @Juhunio Oh man, I've just seen this. Although what I told you was correct, it never occured to me that you wouldn't be using the seperate receiver batteries. However I do know what a BEC is and what it's for, and definitely should have been more careful before clicking submit reply. Feels bad. If you PM me your paypal, I'm happy to cover the cost of a replacement receiver. 1 Share this post Link to post Share on other sites
Juhunio 6830 Posted September 14, 2020 16 minutes ago, Fuijo said: @Juhunio Oh man, I've just seen this. Although what I told you was correct, it never occured to me that you wouldn't be using the seperate receiver batteries. However I do know what a BEC is and what it's for, and definitely should have been more careful before clicking submit reply. Feels bad. If you PM me your paypal, I'm happy to cover the cost of a replacement receiver. That's very decent of you, but really not necessary mate, this is all a learning curve and I've already made more expensive mistakes than this! So, I really appreciate the offer, but don't worry about it. Enjoy your week! Share this post Link to post Share on other sites
Grumpy pants 4485 Posted September 14, 2020 Interesting reading this, I tried getting my Super Champ with its vintage servos and msc to run using my Flysky radio set a couple of months ago. No signs of life of any description. Sold the car, kept the radio gear. 1 Share this post Link to post Share on other sites
Juhunio 6830 Posted September 15, 2020 15 hours ago, Grumpy pants said: Sold the car, kept the radio gear. Weren't you tempted to ditch the old electrics, put new electrics in the classic chassis and keep it? Share this post Link to post Share on other sites