Blown TTS Decoder - what did I do wrong?

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RAF96
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Re: Blown TTS Decoder - what did I do wrong?

Postby RAF96 » Thu Dec 13, 2018 5:20 pm

Do a con test twixt each socket hole (grey and orange) to each motor brush. Grey to brush 1 and 2, ditto orange. You should only get con between the direct connections and not between the crossed connections.
May or may not give us a clue.
Any way that either of those wires is shorting to chassis. You did do a bare motor con check from each brush to each wheel set, should have both been isolated.
Rob
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NedFlanders
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Re: Blown TTS Decoder - what did I do wrong?

Postby NedFlanders » Fri Dec 14, 2018 1:05 pm

RAFHAAA96 wrote:Do a con test twixt each socket hole (grey and orange) to each motor brush. Grey to brush 1 and 2, ditto orange. You should only get con between the direct connections and not between the crossed connections.
May or may not give us a clue.
Any way that either of those wires is shorting to chassis. You did do a bare motor con check from each brush to each wheel set, should have both been isolated.
Rob


Hi Rob,

thanks for the suggestions. I have done the grey/orange socket to grey contact /orange contact and Vice versa and the results are as expected - i.e. no evidence of a short. the only beep is when I probe the Orange socket and the Grey Socket.

Tests between the motor contacts and the wheel pickups are suitably silent as well.

I haven't had a chance to do a stall test on Flying Scotsman yet - I'll try that over the weekend to see what she draws.

I think I will remove the socket and put in another one and see if I have the same result with the unknown beep between grey and orange socket. I have a new commissioning test as a result of this escapade.

I suspect my TTS CHIP is toast, so just in case, I won't test with another TTS chip until after Christmas. That way the Small Controller wont lose one of his sound locos. I do have a spare DCC concepts with Stay alive that I haven't fitted to a likely suspect yet so I may use that to prove the new socket on Scotsman before I get another TTS chip for it.

Cheerio.

Ned.
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NedFlanders
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Re: Blown TTS Decoder - what did I do wrong?

Postby NedFlanders » Fri Dec 14, 2018 1:34 pm

NedFlanders wrote:I think I will remove the socket and put in another one and see if I have the same result with the unknown beep between grey and orange socket. I have a new commissioning test as a result of this escapade.



not being hungry for lunch just yet, I idly replaced the socket with one that tested fine - i.e. no beep between any pin socket.

after fitting to the loco - beep between grey and orange socket!

Cue Ned grabbing another tts loco and without removing the chip plug I tested the contacts on the back of the Chip plug - i.e it was left plugged into the socket - results.... drum roll please..... yup - there's a beep between grey and orange pins..... Lunch is calling now so I've put them all to one side to think about that one.

the multimeter reads 26 on flying scotsman and 14 the another ( tested ok ) TTS loco with a factory fitted dcc 8 pin socket. So perhaps ( on my multimeter) this is perfectly normal - I have two other TTS locos to test so I will do that when I have more time - it would be interesting to see if anyone else gets a similar result?

If its normal to some degree then we are looking back at a foible of Scotsman or a faulty chip in my case methinks.

Cheerio,

Ned.
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Bigmet
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Re: Blown TTS Decoder - what did I do wrong?

Postby Bigmet » Fri Dec 14, 2018 1:55 pm

NedFlanders wrote:Ok, this one is hurting my head - the orange and grey wires go from the socket to the Motor contacts.

Test at the Motor contacts - no beep from the Multimeter.

Test the Orange and Grey Pin holes on the socket - Beep! ?

The orange and grey pin holes are at the opposite ends of the socket - where could a bridged connection be coming from? If I get a beep at the pin holes surely I should get a beep at the motor contacts?...

Really you want to make fuller use of the meter, and look at the resistance in the circuit sections under test.
From the decoder socket motor connection to the brush connection on the motor, both orange and grey wires, there should be negligible resistance (the test as suggested by RJ).
Across the brush connections - through the motor - there should be a circuit. If there isn't no chance of the motor working! But it should show some impedance, a dozen ohms or thereabouts would be normal. If as you rotate the motor there is a section with no conduction, then you have probably lost a winding, or there is some other derangement within. Don't attempt to fit a decoder in this case, the motor must be repaired.

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RAF96
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Re: Blown TTS Decoder - what did I do wrong?

Postby RAF96 » Sun Dec 16, 2018 2:57 pm

I was just about to say there will be a beep across the orange and grey with a motor in circuit for the reasons provided above.
Rob
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NedFlanders
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Re: Blown TTS Decoder - what did I do wrong?

Postby NedFlanders » Mon Dec 17, 2018 10:47 pm

RAFHAAA96 wrote:I was just about to say there will be a beep across the orange and grey with a motor in circuit for the reasons provided above.
Rob


Thanks Bigmet and Rob, I'll have to go back to basics on electrickery for that one - I suspect its along the lines of "for a filament bulb to work there has to be a short of sorts - i.e. something to consume/allow the movement of electrons" - ergo the beep in this case.

This evening I got around to testing the original speaker on the TTS chip by resoldering it back onto the TTS chip. - the chip responds perfectly to the Elink/railmaster - reporting all CVs - however there is no sound - also it is responding fine to movement commands - albeit on the 72 address and not the 03 - which suggests that it actually did take some of the commands the last time. the only difference to the last time is that I have removed the sugar cube speaker and put back the TTS speaker.

Can you blow just the sound element of a TTS chip perhaps? If yes ( or perhaps I've just proved that I can), then its not a total loss as I have a perfectly good "mute" chip for another loco. It does beg the question - was my new 8 ohm not an 8 ohm speaker or faulty chip or user error or ......?

Details here:
I bought this speaker- https://www.ebay.ie/itm/ESU-50321-DCC-S ... 2749.l2649
Youtube video on the speaker https://www.youtube.com/watch?v=YXnF5Qgygug
Hornby tts needs 8 ohm - confirming what I read on the TTS sheet with the chip https://hornbymagazine.keypublishing.co ... selection/

I might have a rattle off Hornby as you suggested Rob to see if I can get the "accidental" damage warranty - or just plain get it tested to confirm the dead sound element of it.

Thanks,

Ned.
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Bufferstop
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Re: Blown TTS Decoder - what did I do wrong?

Postby Bufferstop » Mon Dec 17, 2018 11:56 pm

You can test the 8ohm speaker using your multimeter. Don't expect to measure 8ohms, that's it's impedance not the DC resistance, but put the meter onto a low ohms range touch the speaker leads with the meter probes, you should get a low ohms value and a slight tick from the speaker each time you make contact with it, you may also be able to see the speaker cone move.
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NedFlanders
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Re: Blown TTS Decoder - what did I do wrong?

Postby NedFlanders » Tue Dec 18, 2018 1:01 pm

Bufferstop wrote:You can test the 8ohm speaker using your multimeter. Don't expect to measure 8ohms, that's it's impedance not the DC resistance, but put the meter onto a low ohms range touch the speaker leads with the meter probes, you should get a low ohms value and a slight tick from the speaker each time you make contact with it, you may also be able to see the speaker cone move.


Cheers,

Very much a Senior moment - "hmm, how would I measure the Ohms???" Doh! as Bufferstop says, move the Multimeter to the Ohms section. i think my recovery for some joint surgery on my foot has affected both my eyesight and my observation coefficient! :lol:

The Sugar cube reads as just below 8 ohms - 7.5-7.8.

So no problem there - perhaps.

thanks all. I will rattle Hornby's cage next as it looks to me that I haven't done anything fundamentally wrong as yet so over to them.

Ned.
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NedFlanders
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Re: Blown TTS Decoder - what did I do wrong?

Postby NedFlanders » Wed Dec 19, 2018 12:40 pm

As an aside - is there a +/- side to speaker connectors? I didn't see any in the instructions/ online videos and a quick search here hasn't shown anything to me.

From previous experience with HiFi speakers I understood that if you had two speakers it was a matter of making sure both speakers were connected to the same "poles" on the back of the hi-fi e.g right speaker connector to Black and red to the left on both - or vice versa but not mixed.

( hornby have asked me to reset the chip -Done, and i still have no audio output, waiting for their next reply)

Thanks

Ned.
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Bigmet
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Re: Blown TTS Decoder - what did I do wrong?

Postby Bigmet » Wed Dec 19, 2018 1:33 pm

If you are using two speakers on one audio output, then if they are an identical pair, wire alike, if not identical look for any indication like coloured insulators on the tags, and if there is nothing to help, then judge by listening. Two speakers connected to the same source in antiphase should lead to cancellation resulting in audible volume reduction over at least some of the frequency band, best heard when placed close together (which they usually will be in a loco).

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NedFlanders
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Re: Blown TTS Decoder - what did I do wrong?

Postby NedFlanders » Wed Dec 19, 2018 2:09 pm

Bigmet wrote:If you are using two speakers on one audio output, then if they are an identical pair, wire alike, if not identical look for any indication like coloured insulators on the tags...


Sorry Bigmet, it was a general question in case there was a chance I could have wired the sugarcube speaker ( only one in this case) wrong in Flying Scotsman. I was using the Hifi as an example. When I reattached the TTS supplied speaker I still had some black cable on it so I connected it back up the way it had been supplied so I think I'm good there. For the sugarcube I couldn't find any evidence that it would make any difference, but it doesn't hurt to ask.

Thanks for the reply.
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