Issues with Aristo 5471/5473 rx/tx

dunnyrail

dunnyrail

DOGS, Garden Railways, Steam Trains, Jive Dancing,
25 Oct 2009
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St.Neots Cambridgeshire UK
Yet another excuse for me to post this cantankerous cat here -

View attachment 250945

P.S. Phil that looks interesting. Nice compact installations. Could see one trailing a Shay/Climax/Heisler. Now how do we speed up a MyLocoSound card to get the right chuff rate. :D Max
Aha Ge_rik does a Vid of that, but it is easy enough. On my instruction sheet Page 7 refers to the Chuff Rate on Button 7 in the text there. Set Loco on a set of Rollers and you should be able to follow those notes. I refrained from exact description as the remotes can differ in the way they work to set up those Chuff rates. But it can be done to get 4/6 or even 8 chuffs per revolution of the wheels.
 
PhilP

PhilP

G Scale, 7/8th's, Electronics
5 Jun 2013
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Tamworth, Staffs.
P.S. Phil that looks interesting. Nice compact installations. Could see one trailing a Shay/Climax/Heisler. Now how do we speed up a MyLocoSound card to get the right chuff rate. :D Max
You use the throttle to increase the 'chuff' on the MLS.. But let's face it, on a rod-driven loco, it just needs to chufflikemad! ;):):)
 
D

Dan

Registered
28 Jan 2010
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Eastern MA
The Aristocraft 27 mhz are known to have leaky mosfets. I have a voltmeter (VOM style) on my track and with no engines or cars on the track the meter goes over 10 volts from this leakage. If you have a digital meter your readings will read higher as digital meters have a lower load than coil meters. Been this way for more than 15 years!!
 
maxi-model

maxi-model

UK/US/ROW steam narrow gauge railways 1:1
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The Aristocraft 27 mhz are known to have leaky mosfets. I have a voltmeter (VOM style) on my track and with no engines or cars on the track the meter goes over 10 volts from this leakage. If you have a digital meter your readings will read higher as digital meters have a lower load than coil meters. Been this way for more than 15 years!!
Not sure what you are saying Dan :wondering: I am just a poor simpleton in these matters, even after 15 years with a garden railway. I am asking as I have not ever had readings like this, voltage seemingly stuck at a midpoint and no action from the motors or lights (just a little spark from betwixt loco wheels and rollers at one point) - in over 15 years of ownership of the same Aristo TE combo' and digital meter. As mentioned both tested locos were on the rollers/track at the time.

No idea what a "mosfets" is nor a "VOM style" meter - I have now Googled and now understand the TLA, though I still have a somewhat near nonexistent understanding of the former - but I have bookmarked this How To Use MOSFET - Beginner's Tutorial - Oscar Liang to take a little look at later :)

It does seem to have "cleared" itself and all appears to be functioning as it should again. Just wondering now what could have caused the apparent temporary issue. I suppose it must be those pesky mosfets. But why now after 15 years ? Are they getting old a a little bit cranky like me ? :D Max

Edit - Having had a quick look at the "tutorial", are those "mosfets" the things sitting in that dirty great heat sink near the top of my picture of the 5473's innards in an earlier post. What do they say - "A little knowledge is a dangerous thing" ? I shall leave well alone but could they be replaced if needs be ?
 
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PhilP

PhilP

G Scale, 7/8th's, Electronics
5 Jun 2013
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Tamworth, Staffs.
Anything can be replaced / repaired.. Whether you can find someone to take the job on, ans whether it would be cost effective, ia a moot point.

i would guess, either the electronics got confused (doubtful, if multiple power-cycles were involved) or more likely, either dirty/poor connection somewhere, or a loose wire causing a short, and the unit to shutdown.

I would clean track the rollers sit on. area of rollers that picks-up from track. rollers. Wheels / tyres / wheel-backs / check wipers and/or brushes..

Then would give the loco a good shaking, abd try again. - Do this a couple of times, we are looking for an intermittent fault.

If still all good, put it down to another unexplained mystery, of 'elektrickery'.. :think::)
 
Neil Robinson

Neil Robinson

Registered
24 Oct 2009
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N W Leicestershire
I shall leave well alone but could they be replaced if needs be ?
I suggest you read this:-
That link is to part of a highly respected website.
Based on it I recommend you leave the train engineer alone with the exception of adding a resistor to the output as suggested. Personally I'd go OTT and fit a 100 Ohm 10 Watt resistor. All you'd need to do is bend and cut the resistor leads to suit and fix it to the output terminals with the same screws used for the output wires to the track.
 
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maxi-model

maxi-model

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Thank you for the link Neil. I forgot about checking Mr Schreyer's handy tips site - well thumbed over the years by myself, in a virtual sense. The only problem is I cannot understand a word of what it is saying there. It's all in Electroneze, even the schematics are mostly like strange hieroglyphics to me. Although bits of it do seem to ring a bell as to what I was witnessing. As for what you suggest I cannot even start to visualize that. I am that ignorant in these matters :) Putting a resistor across both terminals sounds like one is creating a short (See, I really do not understand how these things work).

I suppose I'd better get round to Googling 100 ohm 10/5 watt resistor - Edit, just had a very frustrating time looking at RS Components, and others, being unable to isolate the specific one as there are no drop downs to fill in the spec' :banghead: - And loads of symbols I do not understand and no direct link to products shown. Keep trying to tell you all I'm a complete numpty at these things. Is there a book, DC garden railways for dummies ? :D Max
 
maxi-model

maxi-model

UK/US/ROW steam narrow gauge railways 1:1
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Bucks/Oxon/Northants area
Thank you John. Demystifier bookmarked. I've got my feet up for a couple of weeks so I will take time to read and inwardly digest this and other information links given here. That resistor looks like one I found on a US site but could not locate here 8n the UK. What would be the benefit of installing one and why was this not a standard fitment from new by Aristo' ? Max
 
maxi-model

maxi-model

UK/US/ROW steam narrow gauge railways 1:1
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OK, although it appears all is well now with my Aristo' TE tx/rx combo' I reckon it might be prudent to follow the advice from the good Mr Schreyer and others here and buy and install a 100 ohm/10 watt resistor across the track output terminals of the 5471 rx. Before I plug it in and pump some juice through it could someone take a look at the picture and confirm I have not misundersrood something and about to consign this unit to some terrible terminal event. The resistor (as if I needed to tell any of the knowledgable souls here) is the gold bit (says HS10 100 R J on the case) screwed to the side of the 5471. I chose that one as it could be screw fixed to the 5471's plaxtic body rather than flapping around loose.

Silly question, amongst thhe many I have posted of late - Will I notice any difference in its operation as a result ?

Found a supplier, Farnell, who would supply in single rather than multiple units. I also took the opportunity to replace the 10 amp quick blow fuse holder, that had degraded somewhat over the years, with a new one from the same source. Easy to use/search web site and excellent quick and free delivery by UPS. Usual disclaimers apply. :) Max


121449_037ed69121a4ffa3e4627cbb85c1b15e.jpg
 
PhilP

PhilP

G Scale, 7/8th's, Electronics
5 Jun 2013
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Tamworth, Staffs.
As regards the wiring: That looks fine.

As regards 'any difference': The unit should not 'hang', as it did for you.

As regards where it is mounted: What is the case made from? - It is a chunky resistor, and will get warm. Especially outside in full-sun.

Check how hot it is, frequently but carefully (burnt fingers, if hot) during your first-run with it fitted. - Better safe than sorry.
 
maxi-model

maxi-model

UK/US/ROW steam narrow gauge railways 1:1
27 Oct 2009
4,478
131
Bucks/Oxon/Northants area
The case appears to be anodized aluminium. The 5471 rx is kept out of the sun as is the transformer. Could put a bit of insulation between it and the plastic body (though the brass screws might conduct some heat) a bit of 2 mm cork perhaps ?

I remember how hot some of the 12v max 1/1.5 ohm resistor fitted MRRC throttles we used with some of the wildly wound 16D motors installed in our 1:24 slot cars. I can't remember how many amps those motors were drawing too but it was the norm to give them a blast from a can of butane after a 5 minute race to cool them down - those cars had a real not scale speed 70 mph. Max
 
Greg Elmassian

Greg Elmassian

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It's pretty easy to calculate the maximum power dissipation of the resistor, take your max output voltage, divide by the resistance and you have your current.

then voltage times current is wattage... run the resistor at NO MORE than 1/2 it's rated value (you CANNOT run a resistor at it's rated value it will overheat, and definitely melt plastic)

So you 10 watt resistor should run at 5 watts max... and it will be warm then... but not burn you.

If you could supply the output voltage, I could do the calcs here... from the picture it appears you are at the 12v setting

so V=IR or I=V/R or 12/100 or 0.12 amps, so W=VI or watts = 12 * 0.12 or 1.44 watts... so you are well within the safety limits and should have no heat issues.

Greg
 
maxi-model

maxi-model

UK/US/ROW steam narrow gauge railways 1:1
27 Oct 2009
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131
Bucks/Oxon/Northants area
Thank you Greg, I think I understand that.

The Crest transformer is usually set at 13.8v max but can be switched to 22v. All my track powered locos are Bachmann, with the largest being my K-27's (the Accucraft one is battery powered now, See other threads :D). While I do not keep my eyes like a hawk on the Crest power unit's inbuilt ammeter I generally do not see much above 1.5 - 2 amp current draw when I do. I do not run my locos at any high speed, a scale 25 mph (yes I have a waggon calibrated for 1:20.3 operation) or heavily loaded. Track is level but due to the confines of the garden they can spend about 1/3 the lap on 4-6 ft curves. Max
 
Greg Elmassian

Greg Elmassian

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So 13.8v is 13.8/100 amps, or .138 amps times 13.8v = 1.9 watts... still ok..

At 22v, you are coming close to exceeding the operating voltage for your TE, and also would be 4.84 watts, still ok on the wattage, but it will be hot, and could soften plastic at prolonged high voltages.

I know the system is speced to run to 24v dc... and I know it is a 10 watt resistor. If you run at 22v I would suggest mounting the resistor to a larger flat plate of metal, and making physical contact not possible.

Greg