Eastwood Town - A tribute to Gordon's modelling.

[lezz01]

Sorry Gordon, I've got nothing else mate, that worked for mine.

Regards Lez.

[Barry O]

The wiring in the class 28C is strange. Somewhere down the line it has popped the sound chip fitted to mine. .which reminds me..I must get a new chips. .

Baz

[Regularity]

13 hours ago, lezz01 said:

Hattons cl28's lights do not work if the decoder plug is in the wrong way around. The #1 end is the BO end not the CO end. When you look at a 28 it looks like it should be the other way around but if you put the #1 pin at the BO end they should work fine if you get it the wrong way the lights won't work.

I always thought that the #1 end was the one with the radiator? (dual-engined locos excepted, of course)?

Have Hattons got it wrong?

[gordon s]

Just taken a break from ballasting as golf was carry only, so another day at home.....

 

Here the Class 28 board. Pin 1 is indeed at the Co end. My assumption is that the square pad is pin 1. In any case I tried it the other way round and nothing worked. I did make a start on testing each individual board with a 9v supply and 1500 ohm resistor, but then something else took over, so I'll have another go this afternoon.

 

If you are really clever you should be able to follow the tracks through. I shall do the same with a meter later today and will then be able to tell you which led goes to which pin on the decoder.

 

 

 

[Michael Edge]

1 hour ago, Regularity said:

I always thought that the #1 end was the one with the radiator? (dual-engined locos excepted, of course)?

Have Hattons got it wrong?

Yes, No1 end is the radiator end in single engined locos.

[RedgateModels]

7 minutes ago, Michael Edge said:

Yes, No1 end is the radiator end in single engined locos.

 

Apart from Hymeks where the "A" end is the non radiator end

[gordon s]

OK, bussed it all through with a meter.

 

 

 

1 = Orange - Motor connection

2 = Yellow - Function Output B

3 = Green - Function Output C - not connected on PCB

4 = Black - Left Rail Pick up

5 = Grey - Motor connection

6 = White - Function Output A

7 = Blue - Function Common

8 = Red - Right Rail Pick up

 

Connections and logic all seem fine, (unless you can see something obvious I've missed), so can only be wiring to led's or faulty or failed led's.

 

Further tests to follow on the individual boards later......

[5BarVT]

That looks like a standard Heljan pcb- single sided so nothing hidden as far as I recall, and nothing to go wrong.

Bromsgrove models decoder fit web page confirms that pin 1 is by “NMRA” writing.

Paul.

[Ian_H]

Hi Gordon,

 

I'm going to have to educate myself about DCC at some point but from a practical point of view, is not possible to test the DCC chip thingy in another locomotive that will use the same outputs for the led lamps?

 

Just a thought ....... as I admitted I don't know anything about DCC!

 

Ian

[WolfofBadenoch]

4 minutes ago, Ian_H said:

Hi Gordon,

 

I'm going to have to educate myself about DCC at some point but from a practical point of view, is not possible to test the DCC chip thingy in another locomotive that will use the same outputs for the led lamps?

 

Just a thought ....... as I admitted I don't know anything about DCC!

 

Ian

 

That's a good suggestion and one i often do myself. Another similar one is to try a different chip that you know works fine in a different loco.

[gordon s]

1 hour ago, 5BarVT said:

That looks like a standard Heljan pcb- single sided so nothing hidden as far as I recall, and nothing to go wrong.

Bromsgrove models decoder fit web page confirms that pin 1 is by “NMRA” writing.

Paul.

 

Good to know my assessment of Pin 1 was correct.

 

It's actually a double sided board with plated through holes. If you look at pins 1 & 2 you can see the plated through holes taking the feed through the board to tracks on the back. I started my electronic working life as a PCB designer. In the good old days it was all done with black tape and sticky pads. Double sided boards were laid out with red and blue translucent tape to represent the front and back connections. The producer then used camera filters to eliminate the red or blue, so boards could be manufactured with the correct tracks on each side.

 

Really showing my age now as this was long before CAD.......

 

I have tried every combination known to man of decoders and my initial tests with a 9v supply and resistors did show some of the led's didn't work at all.

 

More to follow....:-)

Edited March 12, 2020 by gordon s

[BoD]

32 minutes ago, gordon s said:

 my initial tests with a 9v supply and resistors did show some of the led's didn't work at all.

 

That sounds fairly conclusive to me.

[Barry O]

unplug the cables from the lights ..make sure you see which one goes where. plug one in and if it works try the other connectors in that slot.

 

Hattons and Heljan made a mare of the wiring then modified it all. The box should have a sticker to say its been modified by Hattons.

 

Baz

[trustytrev]

Hello Gordon,

          It might be worth looking at the decoder socket pcb through pins more closely. I have come across poor soldered connections on the underside with the pins. Testing with a meter causes them to make contact due to pressure from the probe of the meter pressing them together. A real head scratcher at the time.

trustytrev.

[gordon s]

Thanks Trev, I will check that as I go. I have two boards out on the bench with a 9v battery. One board is OK with all three led’s working. The second board has one duff yellow. Both boards are from D5707 which confirms my earlier findings in my LED Boards topic.

 

Replacing one led should fix everything. It’s easy to say but I have no idea where to get replacements from. I did a quick measure and they appear to be 2.8mm long x 0.8mm wide. Had a quick Google and that exact size doesn’t jump out at me yet.
 

Then I need to learn how to solder SMT components....

 

[The Stationmaster]

On 04/03/2020 at 23:48, St Enodoc said:

That's a new one on me. I thought that 34 was the originally-intended classification for what became 33/1.

Exactly so.  The last of the LMS twins went in 1966 I believe - so two years before the BR standardised diesel class numbering system was introduced.  Originally the SR Cromptons were intended to be split into two separate classes but that never actually happened AFAIK because the idea of sub classes emerged instead. 

[St Enodoc]

15 hours ago, Michael Edge said:

Yes, No1 end is the radiator end in single engined locos.

 

15 hours ago, RedgateModels said:

 

Apart from Hymeks where the "A" end is the non radiator end

This is interesting. I had in the deep recesses of my memory, although I didn't post because I wasn't sure, that No 1 end corresponds to the free end of the engine and that in nearly every case that's where the cooler group is. I'll try to find some old BR training notes to see if I'm right or not.

[Barry O]

9 hours ago, gordon s said:

Thanks Trev, I will check that as I go. I have two boards out on the bench with a 9v battery. One board is OK with all three led’s working. The second board has one duff yellow. Both boards are from D5707 which confirms my earlier findings in my LED Boards topic.

 

Replacing one led should fix everything. It’s easy to say but I have no idea where to get replacements from. I did a quick measure and they appear to be 2.8mm long x 0.8mm wide. Had a quick Google and that exact size doesn’t jump out at me yet.
 

Then I need to learn how to solder SMT components....

 

Perhaps Gaugemaster can help. They are now the spares people for Heljan.

Baz

[gordon s]

They were my second port of call after Hattons a couple of weeks ago. The boards don’t even appear on the parts diagram and Gaugemaster said they checked their stock and with Heljan with no joy. I may try Heljan direct and see if I have any luck. Current batch production methods mean spare parts are a thing of the past.

 

The first problem for me is identifying the led’s and then a source. I suspect anyone working in the electronic component industry would recognise them straight away and a few seconds with a soldering iron would solve the problem.

 

If all else fails, I’ll just run them without lights. We never had lights in the past and they are so low level, you can barely see them anyway.

 

I’ll keep searching......

Edited March 13, 2020 by gordon s

[Ray H]

I've just borrowed this from the Internet. Don't know if it is of any use.

 

SMD LEDs are available in four sizes, which are designated 1206, 0805, 0603 and 0402 .

 

0402 is the smallest, with overall package size of 1.0 mm x 0.5 mm x 0.45 mm (L x W x H).

 

Then 0603 at 1.6 mm x 0.8 mm x 0.6 mm.

 

0805 are slightly larger, at 2.0 mm x 1.25 mm x 0.8 mm.

 

1206 are the big brothers of the family, at 3.2mm x 1.5 mm x 1.1 mm.

[gordon s]

Thanks Ray. I did see that yesterday when I was looking. These appear to be 2.5mm x 0.8mm x 0.5mm (L x W x H) so fall outside all those dimensions. I know I have one board that is OK from the D5707 and will strip D5700 this morning. Hopefully I may get one good one although from my earlier testing that's unlikely to be the case. This was from my other thread...

 

D5700 

 

Decoder end 1 yellow and no red

Other end  1 yellow and 1 red.

 

D5707

 

Decoder end 2 yellows and 1 red. This is correct and all boards should behave the same.

Other end 1 Yellow and 1 red.

 

My secondary testing yesterday would appear to support my initial findings. Next step will be a mail to Heljan in Denmark to see if I get anywhere direct.

[eldavo]

Generally using a soldering iron on surface mount components is the hard way of doing things. Solder paste and a hot air gun is much easier. I use my old Black and Decker paint stripping gun!

 

Cheers

Dave

 

[Bloodnok]

On 11/03/2020 at 11:46, gordon s said:

I've tended to use Zimo MX630 decoders in most of my locos as the running quality is silky smooth. Of course it's an overkill putting a six function decoder into a steam loco, but they are small and do the job. If anyone has a decent alternative they can recommend, I'm all ears as at £34 each, they are not the cheapest.

For an 8 pin decoder, have a look at Zimo's MX600R. Features wise they have everything I expected from a Zimo chip and the running quality was excellent. I did a head-to-head comparison with a more expensive MX635R and couldn't tell the difference in practice (even though the latter was nearly double the price and included a stay-alive capacitor). The only thing of note is the current rating is lower -- some locos have acquired a reputation for high current draw, and while a 1.5A peak / 0.8A continuous decoder will drive the vast majority of locos, it's possible a few might need something a little more meaty.

[gordon s]

24 minutes ago, eldavo said:

Generally using a soldering iron on surface mount components is the hard way of doing things. Solder paste and a hot air gun is much easier. I use my old Black and Decker paint stripping gun!

 

Cheers

Dave

 

 

You sound like an expert. They could be in the post any day soon.....

 

Luckily I have some solder paste and a long time ago, I bought a pencil butane torch. Knew it might come in handy one day.....

[eldavo]

33 minutes ago, gordon s said:

 

You sound like an expert. They could be in the post any day soon.....

 

Luckily I have some solder paste and a long time ago, I bought a pencil butane torch. Knew it might come in handy one day.....

 

Whoa!  Go easy with the flames buddy. You just need hot air (slightly warmer than that which is most prevalent on RMweb).  I will happily have a look if you want components replaced as I have fiddled with these nasty little LED things in the past for N gauge tail lights and the like.

 

Cheers

Dave