What went wrong and why ?

Went flying Tuesday and Saturday this week and took the Pulse 125 both times
Set up is Spekky DX 7 Tx, 6 channel spekky RX with satellite 8 s power from 2x 4s 5000 mah lipos, switch to power both radio and motor. DSM 2
Tuesday had 4 flights out of the Pulse, not a prob. Saturday installed the 2 lipos switched on the TX then the model switch, ie RX and motor ESC gave its usual bleeps, but nothing on any control surface or motor. I always take spare lipos with me to the pilots box, cos its a long walk at Langar, so lipos were swapped. Nothing , totally dead.Not even a bleep to say the ESC was armed.
Back to the pits , wing off , and tried rebinding. Bind plug in , both rx and satellite flashing happily, turned on the TX with bind button depressed, and the lights happily ignored the TX completely.
Put the model back in the car, and on my return home dug out an identical RX and satellite, took out the old one, and the new one works perfectly .
I know the prob is that the first RX has gone faulty, my question is WHY?
It will be intersting to see what Spekky say about it. Poss as in the past "Nothing was found, but to give you peace of mind we enclose a new unit "
Anyone any ideas? and NO, I will not change to Futaba

Garry

I had something similar with a Spektrum rx, I opened it up and there was a minute solder bridge on the throttle signal pin, ran the soldering iron between joints to clean it up and it worked fine after that. Could you have something similar which has come loose under vibration and is now causing a short?

If ou're going to repair a solder bridge, you need to flux the solder first.

Garry
If I read your post correctly initially it armed but no power to the motor and servos. With a change of LiPo nothing at all but back home on a different Rx it all worked.
With that degree of fault variation it begs the question has the old Rx failed or is there a poor connection somewhere?
So my suggestion is get it all working and then put in the old Rx back in straight away. If the old Rx still does not work you can be pretty certain that is the problem particularly if you put the alternate back in again and it all comes to life. Work/fail/work is a pretty stringent component test.

Thanks for the replies folks, much appreciated.
I think both Monz and Q were right, as I installed a 7 channel rx and all worked . So back in with the 6 and nothing. So out on the bench, 6 v put into the rx after inserting the bind plug, straight away the flashing lights and it bound,.took out the bind plug and dead, so waggled the power plug and both lights on, waggled again and both off. Seems as Monz said a bad connection , but my soldering skills are not up to repairing it so sending to HH tomorrow. Monz spotted the fault and Q posted the correct way to check. Thanks to both of you

Garry

Not a prob Eric, and I DO remember the post you mentioned

Garry

Hi Monz can you clarify something for me ? Were you removing the solder bridge ?

I think I could have made myself a bit clearer. It wasn't an intentional solder bridge joining two parts of a circuit, it was a manufacturing fault within the rx where a bit of solder between the live and signal pins was present, causing a short between them. I ran the soldering iron between the two pins and removed the offending bit.

"A solder bridge is an unintended electrical connection between two conductors by means of a small blob of solder."

Ive a new Receiver that refuses to bind popped a used one in and model worked perfectly so sending it back to Sussex Model centre

Thanks for that Monz.
Well I have sent my faulty one back to HH , will post their response as soon as it lands It will be interesting, as its a DSM 2 model 6200

Garry

Garry
You might have spent more on shipping that it is worth!
As an example you can get one here for $14.75 with free shipping!
I will be interesting to see what Horizon do.

As it was very light, and only going to Harlow it cos £2 . I must admit I am curious to see if they will acctually repair it. However, thanks for the link Q, thats a new one on me

Garry

I thought that was it just making sure. I have seen the odd deliberate bridge. Thanks Monz

In my years of experience I can inform you sir the issue was not enough methanol .