R607FS RECEIVER

[Graham Ord]

Hi All
Had a bad experience when my receiver terminals shorted out.
Receiver now useless.
Does anyone know where I can get one or a replacement alternative and get some replacement 3 pin connectors?
It burnt out so bad I cannot work out which wire went where so I will be probably be back for more advice, especially if it affected other parts.

Many thanks
Graham

[Peter Silcock]

Graham 607 went out of production 7/8 years ago replaced by 617 . There are plenty of the latter about but be careful what you pay- I have seen them advertised from £50 to £75!

[Graham Ord]

Thanks Peter
Have you any idea where I can get the wire/plug connectors?
Graham

[Peter Silcock]

Graham not sure which plugs you are referring to. Do you mean the standard rc plugs/leads which plug into the receiver or the special plugs in an Armortek wiring loom? The former can be obtained from model shops or Ebay(type in rc leads) come in various lengths and very cheap.If the latter then contact Armortek for replacement.

[Graham Ord]

Hi Peter
Its these on the melted end of the receiver, a real mess.
I labelled each set of wires with the pin numbers 1 to 7/8 and cut the off but then found out some of the wires cross over onto a different plug.
The ends are so melted I cannot tell which is which now.

Graham

[Peter Silcock]

Wow Graham, what happened - never seen that sort of damage before? Did you put too much voltage through the receiver? You will need to replace all the standard Futaba rc leads - very cheap on Ebay. Other types connected to the receiver vary depending on whether you have the Armortek modules or the 4QDs with rc interface and stand alone Benedini sound system. Post a clear photo of the inside of the tank and people should be able to tell you want you need.

[Mark Heaps]

Does Futaba stand for "F*ck*d Up Totally And Burnt Away" ?

However the photo of the damage does not suggest to me the receiver contacts shorting out or an over-voltage condition caused by a different module. Also in both of those cases, it should not have led to a fire. Protection circuitry should have kicked in or a fuse should have blown so that a fire cannot occur.
The burn damage seems to be centered around connector 1 or 2. Check all the wires that went to the receiver but these two most especially for melting damage to the insulation.
If it was a short-circuit then one of them will show damage along the full length due to the excess current. If the damage is localised to the end nearest the receiver, it has been caused by the fire starting at that point. This would indicate a poor high-resistance connection at that place, either a defective solder joint on the receiver itself or a poorly crimped connector.
Futaba will probably blame the cable manufactor and the cable manufactor will blame Futaba and the resultant damage from the fire will prevent you pinning the blame firmly on either.

[Graham Ord]

Hi All
Electronics has always baffled me.
I will attempt a strip down with plenty of notes/photos along the way.
I hope nothing else is damaged.

Graham

[Adrian Harris]

How do you supply the 5V to the receiver ?

From the topic I presume this is in your scratch built Panzer IV, which I believe uses 4QD controllers etc ?

I would agree with Mark that the damage looks to be centred around the first couple of leads. If you are using a battery to power the receiver, I would guess that the positive and negative wires for one of those two leads shorted together, which would short out the battery through the circuit board tracks on the receiver, hence the widespread damage.

As this looks to have been caused by a short circuit, I wouldn't expect it to have damaged any of the 4QD kit.

Adrian.

[Mark Heaps]

For me it does not look like a short-circuit has caused it.
If that is the case then the circuitry is poorly designed and inadequately protected.
A short-circuit condition should either cause a fuse to blow or a poly-switch to trigger to shut off the supply. A fire should not occur under any expected fault condition.
In an over-voltage condition, a varistor should have blown creating a deliberate short-circuit and caused a fuse to blow, protecting the rest of the circuitry from damage.
(in the vast majority of cases where electronic devices have been damaged by a lightning strike, all that is needed is to replace the varistors and the fuse)
You need to find out where the fire started. Most damage on the underside of the circuit-board would indicate a poor solder joint as having been the cause. Most damage on the connector side would indicate a poorly crimped connector. Poor connection means high resistance, current plus resistance means heat. Too much heat means fire.
Apart from needing a new receiver and I would recommend replacing all the cables going to it rather than re-doing the ends, I would not expect any damage to the external items apart from a blown fuse or two. The fire is likely to have caused a short-circuit resulting in fuses blowing.

[Adrian Harris]

> a fuse to blow or a poly-switch to trigger to shut off the supply

The earliest version of the motion pack included a main power module which provided fused protection for the all the 24V motorised circuits but not for the NiCad receiver battery.

The newer motion packs are much more sophisticated, with both fuses and poly-switches used to provide failure and protection where needed.

Adrian.

[Mark Heaps]

Just to clarify the matter a bit for others who do not work with electrics / electronics there are three normal ways to protect in the case of a short-circuit or excess current flow-
1) Fuse - will blow if the current flow exceeds its rating and will have to be manually replaced.
2) Circuit-breaker - will trip if the current flow exceeds it rating and can be manually reset.
3) Poly-switch - "trips" when the current flow exceeds its rating and resets by itself when the supply voltage is switched off.

All three provide backwards protection, ie they protect the unit providing the power supply from being overloaded by cutting off the supply to the faulty part and allowing it to continue supplying power to other good parts.
Varistors provide forward protection by failing in an over-voltage condition and triggering the fuse, circuit-breaker or poly-switch before this over-voltage can damage the rest of the electronics in the unit being supplied.

[Graham Ord]

Hi All
I will post my strip down and wait for comments about what may be going on.
It is not an Armortek kit but built to Armortek plans with Armortek electronics.

Graham

[Peter Silcock]

Graham - do I remember correctly that you built this model yourself from scratch based on that huge folder of plans produced by Armortek? What an achievement! A few piccies would be great.

[Graham Ord]

Hi All
As requested.
Only have a few pics as with electronics my old computer hard drive packed up and I had no back up. Now do it regularly.
Still investigating burn out of receiver, looks like it was a short/poor connection at the receiver, all other wires are OK. The 3 main fuses in the main input box just after the battery were untouched.

Graham