DIY Power buffer

muns

muns

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Don't forget, power buffers can interfere with CV programming, hence the reason why the Massoth power buffers have onboard circuitry that can switch them out.
 
Zerogee

Zerogee

Clencher's Bogleman
25 Oct 2009
17,029
North Essex
A timely reminder, Mark - and why, for these DIY ones, it's well worth putting an externally-accessible switch or plug and socket arrangement for easy disconnection of the buffer while programming.
Oh, and don't worry - I'll still be buying some "proper" powercap buffers from you for the locos that really need them, these DIY ones are only to play around with and maybe fit as belt-and-braces security to locos where I wouldn't normally bother with a buffer at all! ;)

A quick question to be 100% certain, given that I haven't played around with discrete components like electrolytic caps for many, many years: the 2200uF radial electrolytics that I've just bought have one long wire and one short wire; the shorter wire is next to a broad white stripe on the capacitor casing that has "0" on it. Am I right in assuming that this refers to 0 volts, or "negative", so the shorter wire is the negative (0v) and the longer one the positive (+22v)? There doesn't appear to be either a "+" or a "-" marking anywhere on the casing.

Jon.
 
PhilP

PhilP

G Scale, 7/8th's, Electronics
5 Jun 2013
26,545
Tamworth, Staffs.
Sounds correct..
I think you will find the broad stripe is (in effect) a l o n g negative (minus) symbol, and the '0' you refer to is a minus-sign in a circle.
Long lead positive.
PhilP.
 
ge_rik

ge_rik

British narrow gauge (esp. Southwold and W&LLR)
The convention is for the longer lead to be positive (eg LEDs).

Rik
 
Zerogee

Zerogee

Clencher's Bogleman
25 Oct 2009
17,029
North Essex
Sounds correct..
I think you will find the broad stripe is (in effect) a l o n g negative (minus) symbol, and the '0' you refer to is a minus-sign in a circle.
Long lead positive.
PhilP.
Good thinking, Phil - in fact once I'd taken a pic and enlarged it, it does indeed look like a "-" in an ellipse - looking at it normally it looked much more like an "0"!



Thanks to you too, Rik.

Jon.
 
PhilP

PhilP

G Scale, 7/8th's, Electronics
5 Jun 2013
26,545
Tamworth, Staffs.
Ah, trying to be to clever, and aging eyesight.. Now where did I put that Class 66?
These engines are way to small!

Seriously, have been wearing glasses for a number of years now and it still annoys me when I try to get up close to things..
 
Henri

Henri

refuses to grow up
6 May 2016
1,618
52
Hoeksche Waard - Netherlands
Hi
I'm going to have a go at adding my own power buffer to one of my locos using the info on the Massoth forum

http://forum.massoth.org/viewtopic.php?t=216

Can someone with more electronical knowledge than me advise - will a 1W rated 150R resistor be OK or should I go for a 2W rated one? The one used in the picture on the forum looks like a lower rated one to me.



Rik
Ordered the parts! Per set it costs me Euro 1,20...
 
Zerogee

Zerogee

Clencher's Bogleman
25 Oct 2009
17,029
North Essex
Henri - don't forget that these very simple DIY power buffers are ONLY for use on DCC control systems (with "chipped" locos) - not for analogue DC. For DC operation, I think you need the slightly more complicated one as shown in Greg's diagram, post no. 18 in this thread......

Jon.
 
Melbournesparks

Melbournesparks

Registered
30 Sep 2015
227
City of Eltham
The straight DC version is pretty simple, you just need one capacitor for each direction since they're polarity sensitive.



This is all there is to it, a pair of capacitors and diodes. The two wires go in parallel with the motor.

I've been fitting these to all rollingstock as standard, they work very well.

I recently fitted one to a piece of LGB rollingstock with a decoder. This time I left the decoder in place (operating in DC mode), and installed the capacitors before the decoder across the input wires from the pickups. Seems to work well, and keeps the voltage regulation for the lighting which is nice. I'm not sure if this would also allow DCC operation, I guess theoretically it would? I guess I'll find out when I (eventually) upgrade...
 
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Jim Prior

Jim Prior

Registered
8 Mar 2016
14
58
Heckington, Sleaford, Lincs
Hi all,

Inspired by Riks blog page (thanks Rik and all who have contributed to this thread), I have purchased components to make my own power buffer.

I want to use this in my LGB/Marklin 99 5015 loco (LGB model 20752, as in my avatar pic to the left) which has the on-board interface board with 28-pin decoder connector and a Massoth 55028 sound & mfx decoder piggy-backed on top of it (this is as supplied from factory).

I have googled for hours trying to find a diagram or photos of the on-board interface board (where all the lights, smoke gen, motor, etc plug in - they don't plug into the 55028 board) so I can figure out where to connect/solder my diy buffer leads.

But I have found absolutely nothing, even after extensive searches here on GSC, and in Marklin and LGB/Massoth forums!!! The onboard interface has several connectors which I can see what they lead to so that helps a bit, but the circuit board has no helpful text next to the connectors, pads or pins (unlike most other decoders which are quite clear).

Has anyone opened up their own 99-5015 loco or can suggest where I might connect the buffer leads without blowing things up? This board is not listed in the other Massoth Wiki pages linked from earlier in this thread (I guess because its a more recent loco).

I can probably probe with a multimeter on the board somewhere after the rectifier chip for the 0v and +ve power, but just wondered if anyone might have this info to hand?

I also have a Rugen with a Massoth XLS decoder which I think will be clearer, but I'm trying the power buffer on my 99-5015 loco first.

Thanks for your help.
Jim
 
PhilP

PhilP

G Scale, 7/8th's, Electronics
5 Jun 2013
26,545
Tamworth, Staffs.
Jim,
The XLS will be easy, as there is information in the manual..

Assuming you are actually using the arrangement in post #25 in this thread??

Then connect your power buffer to Dec +ve and Dec-ve.

I suggest you also have some method of isolating one (or both) of the connections, for if you want to program the decoder in the future. - Power buffers can interfere with decoder programming, unless the decoder is aware of them, and there is a method to control them (as in the commercial offerings).
 
ge_rik

ge_rik

British narrow gauge (esp. Southwold and W&LLR)
Very gratifying to see that this thread and the blog post / video are of value.

I'm sorry, I can't answer your question I'm afraid. In the intervening period between creating the post and now, I have gone over to battery power and radio control and so my knowledge of DCC has withered. Whilst power buffers solved my immediate problem of stuttering locos, I had ongoing difficulties with electrical continuity around the garden. Also, with a lot of my railway being under trees, track cleaning was a bit of a nightmare. After some initial experiments with one battery loco I eventually sold all my DCC gear and have gone exclusively over to battery - no more track cleaning - no more soldering jumper wires across point blades and absolute reliability and slow running. Furthermore, with Deltang equipment particularly, I'd say the costs compared with DCC are considerably less.

Rik
 
Jim Prior

Jim Prior

Registered
8 Mar 2016
14
58
Heckington, Sleaford, Lincs
Hi Phil,
Thanks for the quick reply. You and I met and talked at length at Chasewater Railway in the g-scale model railway attic I believe!

The issue is not with the XLS which is in my Rugen loco.

I'm trying to identify where Dec +ve and -ve are on the 99-5015 loco interface board (see attached picture).
A 55028 decoder then plugs into the top of this.
Yes post #25 is what I will be doing.
I understand also about isolating with a switch before programming, which I will add.

Thanks
Jim
20171030_221245.jpg
 
Jim Prior

Jim Prior

Registered
8 Mar 2016
14
58
Heckington, Sleaford, Lincs
Thanks Rik, glad you're still monitroing this thread.
I hear you about battery power. I've learned a lot from your blog and lovely railway.
But I bought the LGB starter set and will persevere with that for the time being!
Thanks, will keep you posted on progress.
Jim
 
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PhilP

PhilP

G Scale, 7/8th's, Electronics
5 Jun 2013
26,545
Tamworth, Staffs.
Hi Jim,

Best I can do is say to work-back from pages 8 and 9 of the XLS-M1 manual..

http://wiki.massoth.de/images/e/ec/991073_BDA_XLSM1_2015_01.pdf

This gives the designations of the pins. You would then probably need to lift the interface board to trace where the pins end up being connected..
My guess, power-buffers are connected to the decoder, and not to the loco/interface, as they are then under the 'control' of said decoder. - Which with analogue turned off, should prevent runaways.
HTH?
PhilP
 
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ge_rik

ge_rik

British narrow gauge (esp. Southwold and W&LLR)
You guys beat me to it - this is the diagram from the Massoth XL-M1 manual which shows which pin is which. Presumably, inverted, you could work out which socket is which
Massoth XL-M1.jpg
Hope that's helpful.

Rik
EDIT - PS - Reading the above post - it looks like that's exactly what John has done.
 
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ge_rik

ge_rik

British narrow gauge (esp. Southwold and W&LLR)
Thanks Rik, glad you're still monitroing this thread.
I hear you about battery power. I've learned a lot from your blog and lovely railway.
But I bought the LGB starter set and will persevere with that for the time being!
Thanks, will keep you posted on progress.
Jim
Thanks Jim
All the best with your experimentations. Looks like you're getting closer to figuring out what goes where.
Hope the buffer solves the problem - it certainly did for my little 0-4-0s as the video testifies.

Rik