OT - anyone into R/C?

I have a beautiful silver 90 in Land Rover Experience trim, low miles,
high/low ratios, trick suspension, FSH etc - unfortunately it is only a foot
long and works by battery. Everything was OK until I was doing a short
home-made off-road course in the caravan area at Malvern (and entertaining a
couple of kids at the same time) when the steering started to play tricks.
Symptoms as follows: when I switch the main power on, all is OK. If I then
hit the steering button on the remote, either way, the steering starts to
shunt back and forth rapidly. This makes it very hard to steer in a
straight line. I can stop it by a) switching off and on again, and b)
holding one of the wheels still until there is a little coggy buzzing noise,
and then it stops until I next hit left/right on the remote.

I have no idea how these things work, beyond basic common sense. Can anyone
who knows about these things (Rule of Tim etc) give me a pointer as to where
to start looking? I have the full toolkit (jewellers' screwdrivers, kitchen
table, soldering iron). Cheers.

--
Rich
==============================

Take out the obvious to email me.

On Fri, 08 Sep 2006 08:01:54 +0100, Richard Brookman
<[email protected]> wrote:

> ...
> I have the full toolkit (jewellers' screwdrivers, kitchen table,
> soldering iron).

no estwing?

--
William Tasso

Land Rover - 110 V8
Discovery - V8

On Fri, 8 Sep 2006 08:01:54 +0100, "Richard Brookman"
<[email protected]> wrote:

>I have a beautiful silver 90 in Land Rover Experience trim, low miles,
>high/low ratios, trick suspension, FSH etc - unfortunately it is only a foot
>long and works by battery. Everything was OK until I was doing a short
>home-made off-road course in the caravan area at Malvern (and entertaining a
>couple of kids at the same time) when the steering started to play tricks.
>Symptoms as follows: when I switch the main power on, all is OK. If I then
>hit the steering button on the remote, either way, the steering starts to
>shunt back and forth rapidly. This makes it very hard to steer in a
>straight line. I can stop it by a) switching off and on again, and b)
>holding one of the wheels still until there is a little coggy buzzing noise,
>and then it stops until I next hit left/right on the remote.
>
>I have no idea how these things work, beyond basic common sense. Can anyone
>who knows about these things (Rule of Tim etc) give me a pointer as to where
>to start looking? I have the full toolkit (jewellers' screwdrivers, kitchen
>table, soldering iron). Cheers.

Almost no experience but I have seen this with the cheap Nikko (shh)
J**p thing I have, when (nearly) out of range.

Not your batteries (Rc or TX) starting to go down and thus reducing
range is it?

Just something cheap and simple to try before going to far.

David

Richard Brookman <[email protected]> uttered
summat worrerz funny about:
> I have a beautiful silver 90 in Land Rover Experience trim, low miles,
> high/low ratios, trick suspension, FSH etc - unfortunately it is only
> a foot long and works by battery. Everything was OK until I was
> doing a short home-made off-road course in the caravan area at
> Malvern (and entertaining a couple of kids at the same time) when the
> steering started to play tricks. Symptoms as follows: when I switch
> the main power on, all is OK. If I then hit the steering button on
> the remote, either way, the steering starts to shunt back and forth
> rapidly. This makes it very hard to steer in a straight line. I can
> stop it by a) switching off and on again, and b) holding one of the
> wheels still until there is a little coggy buzzing noise, and then it
> stops until I next hit left/right on the remote.
> I have no idea how these things work, beyond basic common sense. Can
> anyone who knows about these things (Rule of Tim etc) give me a
> pointer as to where to start looking? I have the full toolkit
> (jewellers' screwdrivers, kitchen table, soldering iron). Cheers.

I've seen this quite a few times, often on the full sized vehicles.....
exactly how late / many bottles in to the evening was this again?


Lee D

Is this a fully assembled jobbie, or one made from components ie seperate
radio and kit and then you assemeble to the whole lot yourself.

If the former, then you have a problem, unless you know a fair bit about
electronics. I found the performance of my kids cheap nikko was dramatically
reduced after it was tested in the bottom of the pool.

If on the other hand it is a built up model, then you could try switching
the speed and steering servos - although these days I gather that a lot of
the speed controllers are electronic in which case you would have to try and
borrow/beg/buy a servo to try it out with.

Regards
Stephen

Richard Brookman wrote:
> I have a beautiful silver 90 in Land Rover Experience trim, low miles,
> high/low ratios, trick suspension, FSH etc - unfortunately it is only a foot
> long and works by battery. Everything was OK until I was doing a short
> home-made off-road course in the caravan area at Malvern (and entertaining a
> couple of kids at the same time) when the steering started to play tricks.
> Symptoms as follows: when I switch the main power on, all is OK. If I then
> hit the steering button on the remote, either way, the steering starts to
> shunt back and forth rapidly. This makes it very hard to steer in a
> straight line. I can stop it by a) switching off and on again, and b)
> holding one of the wheels still until there is a little coggy buzzing noise,
> and then it stops until I next hit left/right on the remote.

Sounds like a duff servo. Inside the servo is a little potentiometer,
which I guess has either got a broken track, or has **** on it
somewhere. The pot tells the motor where it is, the motor drives until
the pot says the position is "right" by comparing it to the signal from
the transmitter. If the pot is knackered, there is nothing to compare
against.

Steve

"Steve Taylor" <[email protected]> wrote in message
news:[email protected]...
>
> Sounds like a duff servo. Inside the servo is a little potentiometer,
> which I guess has either got a broken track, or has **** on it
> somewhere. The pot tells the motor where it is, the motor drives until
> the pot says the position is "right" by comparing it to the signal from
> the transmitter. If the pot is knackered, there is nothing to compare
> against.
>
> Steve

Yup, my money's on the feedback pot too.

Steve (a different one)

William Tasso wrote:

|| On Fri, 08 Sep 2006 08:01:54 +0100, Richard Brookman
|| <[email protected]> wrote:
||
||| ...
||| I have the full toolkit (jewellers' screwdrivers, kitchen table,
||| soldering iron).
||
|| no estwing?

In my hands, everything becomes an estwing eventually.

--
Rich
==============================

Take out the obvious to email me.

rads wrote:

|| On Fri, 8 Sep 2006 08:01:54 +0100, "Richard Brookman"
|| <[email protected]> wrote:
||
||| I have a beautiful silver 90 in Land Rover Experience trim, low
||| miles, high/low ratios, trick suspension, FSH etc - unfortunately
||| it is only a foot long and works by battery. Everything was OK
||| until I was doing a short home-made off-road course in the caravan
||| area at Malvern (and entertaining a couple of kids at the same
||| time) when the steering started to play tricks. Symptoms as
||| follows: when I switch the main power on, all is OK. If I then
||| hit the steering button on the remote, either way, the steering
||| starts to shunt back and forth rapidly. This makes it very hard to
||| steer in a straight line. I can stop it by a) switching off and on
||| again, and b) holding one of the wheels still until there is a
||| little coggy buzzing noise, and then it stops until I next hit
||| left/right on the remote.
|||
||| I have no idea how these things work, beyond basic common sense.
||| Can anyone who knows about these things (Rule of Tim etc) give me a
||| pointer as to where to start looking? I have the full toolkit
||| (jewellers' screwdrivers, kitchen table, soldering iron). Cheers.
||
|| Almost no experience but I have seen this with the cheap Nikko (shh)
|| J**p thing I have, when (nearly) out of range.
||
|| Not your batteries (Rc or TX) starting to go down and thus reducing
|| range is it?
||
|| Just something cheap and simple to try before going to far.
||
|| David

Thanks. Batteries all good.

--
Rich
==============================

Take out the obvious to email me.

Lee_D wrote:

|| Richard Brookman <[email protected]> uttered
|| summat worrerz funny about:
||| I have a beautiful silver 90 in Land Rover Experience trim, low
||| miles, high/low ratios, trick suspension, FSH etc - unfortunately
||| it is only a foot long and works by battery. Everything was OK
||| until I was doing a short home-made off-road course in the caravan
||| area at Malvern (and entertaining a couple of kids at the same
||| time) when the steering started to play tricks. Symptoms as
||| follows: when I switch the main power on, all is OK. If I then
||| hit the steering button on the remote, either way, the steering
||| starts to shunt back and forth rapidly. This makes it very hard to
||| steer in a straight line. I can stop it by a) switching off and on
||| again, and b) holding one of the wheels still until there is a
||| little coggy buzzing noise, and then it stops until I next hit
||| left/right on the remote.
||| I have no idea how these things work, beyond basic common sense.
||| Can anyone who knows about these things (Rule of Tim etc) give me a
||| pointer as to where to start looking? I have the full toolkit
||| (jewellers' screwdrivers, kitchen table, soldering iron). Cheers.
||
|| I've seen this quite a few times, often on the full sized
|| vehicles..... exactly how late / many bottles in to the evening was
|| this again?
||
||
|| Lee D

If it was a real vehicle, you wouldn't hold onto your lunch. Imagine going
over rough ground with the driver spinning it from lock to lock with a
frequency of about 4Hz. OK, not imagine but remember ...

--
Rich
==============================

Take out the obvious to email me.

fanie wrote:

|| Is this a fully assembled jobbie, or one made from components ie
|| seperate radio and kit and then you assemeble to the whole lot
|| yourself.
||
|| If the former, then you have a problem, unless you know a fair bit
|| about electronics. I found the performance of my kids cheap nikko
|| was dramatically reduced after it was tested in the bottom of the
|| pool.
||
|| If on the other hand it is a built up model, then you could try
|| switching the speed and steering servos - although these days I
|| gather that a lot of the speed controllers are electronic in which
|| case you would have to try and borrow/beg/buy a servo to try it out
|| with.
||
|| Regards
|| Stephen

It's an assembled package. If I'd built it myself I might have an idea
where to look, but I haven't even taken its bottom off. If I can identify
the servos I will try switching them, thanks.

--
Rich
==============================

Take out the obvious to email me.

Steve wrote:

|| "Steve Taylor" <[email protected]> wrote in message
|| news:[email protected]...
|||
||| Sounds like a duff servo. Inside the servo is a little
||| potentiometer, which I guess has either got a broken track, or has
||| **** on it somewhere. The pot tells the motor where it is, the
||| motor drives until the pot says the position is "right" by
||| comparing it to the signal from the transmitter. If the pot is
||| knackered, there is nothing to compare against.
|||
||| Steve
||
|| Yup, my money's on the feedback pot too.
||
|| Steve (a different one)

Steves

Many thanks - that's where I'll start looking. Are these easily
replaceable/obtainable?

--
Rich
==============================

Take out the obvious to email me.

Richard Brookman wrote:

> Steves
>
> Many thanks - that's where I'll start looking. Are these easily
> replaceable/obtainable?

A picture would help.

Steve
>

"Richard Brookman" <[email protected]> wrote in
message news:[email protected]...
> Steve wrote:
>
> || "Steve Taylor" <[email protected]> wrote in message
> || news:[email protected]...
> |||
> ||| Sounds like a duff servo. Inside the servo is a little
> ||| potentiometer, which I guess has either got a broken track, or has
> ||| **** on it somewhere. The pot tells the motor where it is, the
> ||| motor drives until the pot says the position is "right" by
> ||| comparing it to the signal from the transmitter. If the pot is
> ||| knackered, there is nothing to compare against.
> |||
> ||| Steve
> ||
> || Yup, my money's on the feedback pot too.
> ||
> || Steve (a different one)
>
> Steves
>
> Many thanks - that's where I'll start looking. Are these easily
> replaceable/obtainable?
>

You'll need to open the thing up to find out the size - servo's come in a
variety of shapes and sizes. Prices range from a few quid (circa £5) up to
£50 and more!! You only need a cheap one. Available from almost all model
shops (but not usually toy shops!) or a pleth of online sites, although it's
probably cheaper to visit the local shop and get exactly what you need and
also avoid the standard £10 delivery charge! They're usually attached by a
couple of screws through a lug on each end into a mounting plate Important
thing is to find out how the servo connects to the receiver too: is it
hard-wired or does it plug in somewhere. If it's hard-wired it's tricky but
not impossible - involves unsoldering from the receiver circuit board
(noting what goes where first!) and soldering the new one back in place. If
that IS the case though, I'd be tempted to cut the wires off the old servo
and join the wires of the new one to those rather than risk frying the
receiver board with a hot poker! Note that all plugs are not created equal
either, although in effect there are only two types: one has a type of
"ear" to avoid reverse connection and the other doesn't (but it does have a
kind of chamfer to one edge to prevent the same reversed connection). Type
B (aka Sanwa or Hitec type) will plug straight into a type A socket, but not
vice-versa. You can, however, shave the "ear" off type A (aka Futaba type)
and it'll fit type B! On the earless type-B variety, just make sure you
plug black to black if putting it into a socket meant for "eared" plugs and
you'll be ok.

Just one closing note: my experience is from using this stuff with model
aeroplanes not surface vehicles. You might want to consider spending a few
quid extra on a servo with metal gears (the cheapest ones come with a
plastic gear train) to cope with the amount of shock abuse it'll get trying
to keep the wheels under control at a scaled up speed of 2000 mph over
terrain that, in the real world, would be Somme circa 1915!!

The other Steve again.

Steve wrote:

|| "Richard Brookman" <[email protected]> wrote
|| in message news:[email protected]...
||| Steve wrote:
|||
||||| "Steve Taylor" <[email protected]> wrote in message
||||| news:[email protected]...
||||||
|||||| Sounds like a duff servo. Inside the servo is a little
|||||| potentiometer, which I guess has either got a broken track, or
|||||| has **** on it somewhere. The pot tells the motor where it is,
|||||| the motor drives until the pot says the position is "right" by
|||||| comparing it to the signal from the transmitter. If the pot is
|||||| knackered, there is nothing to compare against.
||||||
|||||| Steve
|||||
||||| Yup, my money's on the feedback pot too.
|||||
||||| Steve (a different one)
|||
||| Steves
|||
||| Many thanks - that's where I'll start looking. Are these easily
||| replaceable/obtainable?
|||
||
|| You'll need to open the thing up to find out the size - servo's come
|| in a variety of shapes and sizes. Prices range from a few quid
|| (circa £5) up to £50 and more!! You only need a cheap one.
|| Available from almost all model shops (but not usually toy shops!)
|| or a pleth of online sites, although it's probably cheaper to visit
|| the local shop and get exactly what you need and also avoid the
|| standard £10 delivery charge! They're usually attached by a couple
|| of screws through a lug on each end into a mounting plate Important
|| thing is to find out how the servo connects to the receiver too: is
|| it hard-wired or does it plug in somewhere. If it's hard-wired it's
|| tricky but not impossible - involves unsoldering from the receiver
|| circuit board (noting what goes where first!) and soldering the new
|| one back in place. If that IS the case though, I'd be tempted to
|| cut the wires off the old servo and join the wires of the new one to
|| those rather than risk frying the receiver board with a hot poker!
|| Note that all plugs are not created equal either, although in effect
|| there are only two types: one has a type of "ear" to avoid reverse
|| connection and the other doesn't (but it does have a kind of chamfer
|| to one edge to prevent the same reversed connection). Type B (aka
|| Sanwa or Hitec type) will plug straight into a type A socket, but
|| not vice-versa. You can, however, shave the "ear" off type A (aka
|| Futaba type) and it'll fit type B! On the earless type-B variety,
|| just make sure you plug black to black if putting it into a socket
|| meant for "eared" plugs and you'll be ok.
||
|| Just one closing note: my experience is from using this stuff with
|| model aeroplanes not surface vehicles. You might want to consider
|| spending a few quid extra on a servo with metal gears (the cheapest
|| ones come with a plastic gear train) to cope with the amount of
|| shock abuse it'll get trying to keep the wheels under control at a
|| scaled up speed of 2000 mph over terrain that, in the real world,
|| would be Somme circa 1915!!
||
|| The other Steve again.

Very helpful, thanks. I was going to be out under the S2a this weekend, but
if the weather turns nasty I'll be in the kitchen making with the
mini-screwdriver set.

--
Rich
==============================

Take out the obvious to email me.