Help with Signalling - GWR/WR

[Junctionmad]

Hi folks , attached is a new club 0 gauge layout , grid in feet , Its based on Badminton, but very very loosely based !!

 

Because of space issues , The major issue I have is I need a facing crossover to the left side , which in reality would have been trailing .  

This rather complicates the signalling 

 

The signalling is GWR lower semaphore and ground discs. 

 

Outer homes are not shown 

 

 

comments please , on both signalling and track work, Down platform will not be as long as shown , about 2 feet  shorter then shown , Single slips are all trailing , GWR signalling is not a area I know a lot about in the specifics , A  trap point is needed also at the output of the two goods lines I suspect 

 

The other issue is that Badminton had enough space in the 6' to place single signals, but this track work is O gauge PECO which I suspect will not allow clearances for the signals between two tracks, which leaves me with a further  conundrum as to how to signal this layout 

 

( the arrowed track to the right is the headhunt , the arrowhead is a SCARM artefact ) 

 

the ladder and the crossover to the right of it might look redundant , but the geometry of the track means the platform can be longer if I dont rely on the slip for entrance into the down platform , and that would make it a double slip in practice 

 

thanks and a happy new year 

 

dave 

Edited December 27, 2017 by Junctionmad

[Gordon A]

Some of my observations are that:

a) The double bracket on the down side is superfluous.

 

b) You have not justified the facing crossover on the left hand side.

  The GWR avoided facing cross overs like the plague.

 

c) What is the bay line to be used for?

    I suggest a trap point would be included.

 

d) The entrance to the two sidings would also have a trap point.

 

e) The two single slips on the left hand side would be diamonds. 

 

f) What are the two tail sidings coming off the loops for?

   Consider trap points .

 

g) All trap points would have and associated ground disc.

 

It would be easier to base your station plan on a prototype.

 

Gordon A

[The Stationmaster]

I'm not at all sure why you have dead end sidings off the trailing points into the platform lines - it f you mean them to be sidings they should have trap points and a ground disc to read back towards the platform.

 

I'm not sure what the facing crossover is there for although I can see that you can fit a trailing crossover using off the shelf points (is it there to enable a runround move, if not then why have it?).

 

The dolls reading to the right through the facing crossover appear to serve no purpose one doesn't read to another stop signal at the far end of the platform and the other reads to the wrong road.

 

Trap points need to be included on the line leading from the bay (which presumably is not a passenger line?) and the headshunt.

 

The ladder of single slips are excellently GWR in nature, love 'em, JLTRT especially with the separate lead into the Down Platform line very much like Challow and Shrivenham.

 

The signal arm reading into the headshunt would depend on whatever era when the signal was erected so exactly what you have there will be 'date sensitive' 

Edited December 27, 2017 by The Stationmaster

[RailWest]

Should there not be a starting signal on the Up platform line in rear of the bay/siding connection, but in addition to the bracket at the loop exit?

[Junctionmad]

Thanks

 

To deal with the issues l

 

( a the layout is based on a prototype , a double track main line with two loop platforms , the layout is derived from badminton . But the goods area is considerably simplified

 

I can't add a trailing crossover , without extending the overall length of the layout because of the geometry , it would add another foot , however I may extend the layout as I'm not happy myself with the facing crossover , it also complicates the signalling

 

Stationmaster The thinking behind the double doll to the right of the facing crossover , is an attempt to signal that crossover in the down direction , ie the main arm reads to the main down line , the right hand doll reads to the crossover, I presume you are referring to my infamous facing crossover to the left of the picture ( down to up line )

 

Yes trap points are needed , I mentioned they had been omitted n

 

The two short sidings off the platforms are " refuge " sidings , allowing a station pilot to detach rolling stock, they were suggested by a person of " certain " knowledge , but I'm not sure I like them myself.

Edited December 29, 2017 by Junctionmad

[Junctionmad]

Should there not be a starting signal on the Up platform line in rear of the bay/siding connection, but in addition to the bracket at the loop exit?

Yes unsure about that , the original station plan had this as a goods siding , but we want to use it as a passenger bay

Edited December 29, 2017 by Junctionmad

[DCB]

Thanks

 

To deal with the issues l

 

( a the layout is based on a prototype , a double track main line with two loop platforms , the layout is derived from badminton . But the goods area is considerably simplified

 

I can't add a trailing crossover , without extending the overall length of the layout because of the geometry , it would add another foot , however I may extend the layout as I'm not happy myself with the facing crossover , it also complicates the signalling

 

Stationmaster The thinking behind the double doll to the right of the facing crossover , is an attempt to signal that crossover in the down direction , ie the main arm reads to the main down line , the right hand doll reads to the crossover, I presume you are referring to my infamous facing crossover to the left of the picture ( down to up line )

 

Yes trap points are needed , I mentioned they had been omitted n

 

The two short sidings off the platforms are " refuge " sidings , allowing a station pilot to detach rolling stock, they were suggested by a person of " certain " knowledge , but I'm not sure I like them myself.

 

Yes unsure about that , the original station plan had this as a goods siding , but we want to use it as a passenger bay

 

The Track plan is not really based on Badminton, there are two trailing crossovers between the upper platform line and the main on the Badminton track plan which are missing as is the Goods shed road.  The facing crossover is entirely wrong but several trailing crossovers are missing.  The Signal Box diagram shows 3 single slips in the ladder not just two so lord knows why someone suggested they should be diamonds.

The suggested trap points are not on the prototype either. I think this is due to the interlocking not allowing the conflicting moves involving the passenger lines which I believe would have used the first crossover beyond the platform the remainder being Goods lines, the trap being at the end of the (Up?) upper loop weirdly represented as a Headshunt in the model plan. Check out the prototype and try to understand it. The bay is for loading and unloading Horse Boxes and Carriage Trucks and I would bet a Horse was employed for shunting this bay.   The Goods shed on a loop is a sensible GWR feature. you can access it from either direction.   The Bay is unsuitable for passenger traffic, why would you want one?   Little Somerford just down the line was the Malmesbury branch junction and had just two platforms like Badminton off loops and no branch platform or Bay. The Branch train had to stand clear of the platform when main line passenger  trains arrived.

I think Both Badminton and Little Somerford had 100 wagon loops.

Look at the Prototype plan again and try to understand it  What moves were possible and which were made.  Main line freights would be looped to allow runners past and the same road used for stoppers. There just were not enough trains for this to be a problem. Little Somerford would suit your premise better, it has facing crossovers in the Malmesbury branch ladder    The GWR did not waste money and certainly the Signal Box diagram does not show any of the myriad catch and Trap points some people think should be provided.  They are to protect Passenger Lines as are facing point locks.

Biggest issue will be scale speeds, well into the 90s for up trains like the Bristolian but no Down service, it went via Bath instead.  Several Up trains slipped at Didcot while Down trains slipped at Bath so several London to Weston Down trains went  via Bath and Up trains via Badminton. (Hardly anything GWR started at Bristol in Steam Days)

[Junctionmad]

The Track plan is not really based on Badminton, there are two trailing crossovers between the upper platform line and the main on the Badminton track plan which are missing as is the Goods shed road.  The facing crossover is entirely wrong but several trailing crossovers are missing.  The Signal Box diagram shows 3 single slips in the ladder not just two so lord knows why someone suggested they should be diamonds.

The suggested trap points are not on the prototype either. I think this is due to the interlocking not allowing the conflicting moves involving the passenger lines which I believe would have used the first crossover beyond the platform the remainder being Goods lines, the trap being at the end of the (Up?) upper loop weirdly represented as a Headshunt in the model plan. Check out the prototype and try to understand it. The bay is for loading and unloading Horse Boxes and Carriage Trucks and I would bet a Horse was employed for shunting this bay.   The Goods shed on a loop is a sensible GWR feature. you can access it from either direction.   The Bay is unsuitable for passenger traffic, why would you want one?   Little Somerford just down the line was the Malmesbury branch junction and had just two platforms like Badminton off loops and no branch platform or Bay. The Branch train had to stand clear of the platform when main line passenger  trains arrived.

I think Both Badminton and Little Somerford had 100 wagon loops.

Look at the Prototype plan again and try to understand it  What moves were possible and which were made.  Main line freights would be looped to allow runners past and the same road used for stoppers. There just were not enough trains for this to be a problem. Little Somerford would suit your premise better, it has facing crossovers in the Malmesbury branch ladder    The GWR did not waste money and certainly the Signal Box diagram does not show any of the myriad catch and Trap points some people think should be provided.  They are to protect Passenger Lines as are facing point locks.

Biggest issue will be scale speeds, well into the 90s for up trains like the Bristolian but no Down service, it went via Bath instead.  Several Up trains slipped at Didcot while Down trains slipped at Bath so several London to Weston Down trains went  via Bath and Up trains via Badminton. (Hardly anything GWR started at Bristol in Steam Days)

 

I agree re trap points , they did not exist on the original diagram , which contradicts many comments here

 

As to little somerford , the track work is arguably more complex ( essentially two ladders ) and in O gauge the compromises needed are even more severe , we have around 30-32 feet , 6 foot radius double oval ,which eats up a huge amount of space

 

 

I agree , the GWR liked goods sheds on a loop , but again it is a choice between decent platform / loop length or more prototype goods area representation , it's not possible to do both, especially within the very limited scope of O gauge PECO pointwork

 

I have extensively examined my plan ( which is many iterations at this stage ) for the various movements we would like to run

 

(A) the loops give us the ability to divert slow goods traffic / stopping traffic while mainline fast traffic " thunders through " , aka " classic " roundy roundy. Arguably this was the primary feature of the prototype as the station wasn't more then a halt in reality

 

(B) the single slip laddder is a " characteristic " feature as stationmaster has said, even implemented in limited form here , and allows down line access to the headshunt by using a pilot engine to draw back the freight over the ladder

 

© the bay platform as you said shown as a cattle dock, but operationally we would prefer to signal the bay for passenger traffic, many club members have a single loco and a carriage or two ( again remember this is O gauge ) and the operating premise of the bay is to speculate that a local special traffic left from the bay etc.

 

If I had the space , id implement the goods yard loop as this was a characteristic feature of the GWR , but as I said , I can't fit it in in any meaningful way.

 

I can extend the layout to correct the left hand crossover ( which bugs me anyway and complicates the signalling ) and make it trailing , which is the arrangement at badminton ,

 

Hence we get a " rounds roundy " watch trains go by " playability " , with equally some shunting , station pilot work etc,

 

Bear in mind , the layout is not intended to be a facsimile of badminton , rather more " inspired " by it. The buildings we are using will be " off the shelf " and club members O gauge stock is very varied , expect this layout to see A4s , diesels, etc. as well as some actual GWR stock.

 

thanks again , constructive opinions always are useful and make me think and justify what we are trying to achieve , my own modelling is OO and more more closely based on my specific prototype interest, so this " fictional " stuff is somewhat new to me

[jim.snowdon]

Two immediate observations -

1. Country stations such as this would be unlikely to boast pilot engines, and

2. With a yard layout such as this, it would have been shunted in the Up direction only, when the engine is at the correct end of the train to do the work.

 

Using pilot engines as proposed is something beloved of modellers, not the real railway. But, as modellers, the objective is sometimes to keep an audience entertained, and real railway operation can be quite boring - lots of long intervals between trains. A degree of compromise is sometimes necessary. The trick is doing it in a prototypical manner.

 

Jim

[Junctionmad]

Two immediate observations -

1. Country stations such as this would be unlikely to boast pilot engines, and

2. With a yard layout such as this, it would have been shunted in the Up direction only, when the engine is at the correct end of the train to do the work.

Using pilot engines as proposed is something beloved of modellers, not the real railway. But, as modellers, the objective is sometimes to keep an audience entertained, and real railway operation can be quite boring - lots of long intervals between trains. A degree of compromise is sometimes necessary. The trick is doing it in a prototypical manner.

Jim

1. Of course , but as you say modellers like pilots and hence .... , the layout can of course be operated without a pilot, up freight shunted as normal , and as outlined in 2 below , engine run round for down freight access

 

2. Don't see what you mean here , down freights in the loop,can be drawn into the headshunt by a pilot accessing the rear via the ladder , or by the freight locos running around using the down main , and drawing the train into the headshunt , where it can be shunted as normal, or by detaching the brake van , into the refuge siding , a pilot could add freight to the rear of a stopping freight train , even if they n real life this was not the way it was necessarily done , it does add operational interest

 

The main snafu , is in using the bay for passenger traffic , is there is no access from the down main, so it may have to remain a goods siding as it was intended, that's not a big issue and it's why I didn't put a starter there ( or , the local returning via the down main , deposits its passagners on the down loop,platform and then without passagners can shunt across to reposition in the bay platform, keeping the BoT happy !

Edited December 30, 2017 by Junctionmad

[beast66606]

I agree re trap points , they did not exist on the original diagram , which contradicts many comments here

 

The reason they don't exist on the original is the siding trails into what is a good line, passengers were routed via the crossover from the up platform to the up main, the continuation of the up platform line was goods only, and was protected at the end by traps.

 

On your plan you have moved the connection from the siding to the "passenger" side of the connection and lost the exit connection.

[RailWest]

>>>>The main snafu , is in using the bay for passenger traffic , is there is no access from the down main, so it may have to remain a goods siding as it was intended, that's not a big issue and it's why I didn't put a starter there .....

 

IMHO there is no over-riding reason not to have a bay that is signalled for departure only, if you want one.. Whether the BAY has a main starting signal or just a shunt signal would depend upon its usage. However the use of the bay for passenger or goods is irrelevant to the need IMHO for the main passenger LOOP to have a starting signal in rear of the bay connection.

[Junctionmad]

The reason they don't exist on the original is the siding trails into what is a good line, passengers were routed via the crossover from the up platform to the up main, the continuation of the up platform line was goods only, and was protected at the end by traps.

 

On your plan you have moved the connection from the siding to the "passenger" side of the connection and lost the exit connection.

This is true, I would have loved to fit the loop through the goods shed, but it can't be done , I'll add the traps in

 

I'll add a trap on the goods siding exit and the headshunt , I don't believe the up and down " refuge" sidings need traps or discs , they didn't seem to exist on the prototype as far as I can see ( although I can't see how a loco would be signalled out of the refuge siding in reality )

I'll repost the drawing later today with some corrections and mods

Edited December 31, 2017 by Junctionmad

[Junctionmad]

>>>>The main snafu , is in using the bay for passenger traffic , is there is no access from the down main, so it may have to remain a goods siding as it was intended, that's not a big issue and it's why I didn't put a starter there .....

 

IMHO there is no over-riding reason not to have a bay that is signalled for departure only, if you want one.. Whether the BAY has a main starting signal or just a shunt signal would depend upon its usage. However the use of the bay for passenger or goods is irrelevant to the need IMHO for the main passenger LOOP to have a starting signal in rear of the bay connection.

Yes the starter is an omission from my original sketch , ill correct it ,

 

How would signalling into the headshunt be then done, the bracket shown is too close on the model to the platform if a starter is added back

 

Ps I don't think a passagner bay can be signaled with ground signals

[Junctionmad]

Should there not be a starting signal on the Up platform line in rear of the bay/siding connection, but in addition to the bracket at the loop exit?

Yes , I inadvertently omitted it

[Junctionmad]

Thanks for all the comments so far , I'll update the drawing today and repost for comments

[The Stationmaster]

This is true, I would have loved to fit the loop through the goods shed, but it can't be done , I'll add the traps in

 

I'll add a trap on the goods siding exit and the headshunt , I don't believe the up and down " refuge" sidings need traps or discs , they didn't seem to exist on the prototype as far as I can see ( although I can't see how a loco would be signalled out of the refuge siding in reality )

I'll repost the drawing later today with some corrections and mods

 

The Up & Down 'refuge sidings' were actually catch point overruns at Badminton - in fact one of them even had spring points and the other was only lever worked because it lead to the Main Lines trailing crossover at that end of the station.  At Chipping Sodbury - which generally was very much the same as Badminton - one of these overruns was extended and labelled as a spur although I can't recall how long it was (and it definitely was not regarded as a refuge siding).  There is obviously nothing to prevent them being extended as sidings on the model but they would then need to have trap points and signals of course.

 

Equally I can see no problem in making the bay a passenger bay - in fact it would add some interest to the working as any train terminating at the station, from whichever direction, would have to be shunted to it from the platform it has arrived at (as happened at Bath and Frome).  This would obviously require some changes to the signalling and the addition of a trap point on the good sidings plus provision of a separate starting signal for the bay and (as already noted) one at that end of the main loop platform.  In fact I would wonder if it might be advantageous, if feasible, to copy the layout at Badminton where those sidings are fed directly off the Up Loop extension (headshunt in your case) thus obviating the need for  the two catch points and using the revised connection towards the sidings for that purpose?

[The Stationmaster]

Yes the starter is an omission from my original sketch , ill correct it ,

 

How would signalling into the headshunt be then done, the bracket shown is too close on the model to the platform if a starter is added back

 

Ps I don't think a passagner bay can be signaled with ground signals

It could be done the way you have done - with the addition of a platform starting signal - so it would then be exactly as both Badminton and Chipping Sodbury.  The problem you have on a model railway is the compressed distance which could create a forest of signals if you were to do that.  One (real world) way around it would be to put a co-loacted disc at both the platform and bay starting signals and another at the toe of the crossover which leads to the Main Line.  In view of the compressed distances on the model I reckon you could reasonably omit the disc at the toe of the crossover and just have the other two.

[Junctionmad]

Thanks , based on comments and my own feelings on this layout heres an updated diagram 

 

 

 

[Junctionmad]

 

 

The Up & Down 'refuge sidings' were actually catch point overruns at Badminton - in fact one of them even had spring points and the other was only lever worked because it lead to the Main Lines trailing crossover at that end of the station.  At Chipping Sodbury - which generally was very much the same as Badminton - one of these overruns was extended and labelled as a spur although I can't recall how long it was (and it definitely was not regarded as a refuge siding).  There is obviously nothing to prevent them being extended as sidings on the model but they would then need to have trap points and signals of course.

yes I was aware  they were overruns in reality , but  others in the club suggested they could be better used if extended as sidings, I have now added trap points and discs etc . As you say they re not refuge sidings per se .

 

 

 

Equally I can see no problem in making the bay a passenger bay - in fact it would add some interest to the working as any train terminating at the station, from whichever direction, would have to be shunted to it from the platform it has arrived at (as happened at Bath and Frome).  This would obviously require some changes to the signalling and the addition of a trap point on the good sidings plus provision of a separate starting signal for the bay and (as already noted) one at that end of the main loop platform.  In fact I would wonder if it might be advantageous, if feasible, to copy the layout at Badminton where those sidings are fed directly off the Up Loop extension (headshunt in your case) thus obviating the need for  the two catch points and using the revised connection towards the sidings for that purpose?

I have signalled the bay and added a catch on the goods exit to protect same.  The layout is a little " signal heavy " for a model , but the intention was to do just that !.  I dont think any additional signalling is necessary to work the bay as a passenger line ?.  The plan would be that the bay train , would deposit its passengers on the down platform , and running around its train, ( or it may be a DMU /Autocoach type of thing) , shunt back across the ladder and reposition the train in the bay platform 

 

with PECO geometry , I cant in essence place any point on a inside curve , as the radius isnt available, so Im essentially limited to trackwork diverging from the straight , This limits me considerably, as in essence I have a LH and RH point, a slip and one curved point that I fitted in on the headhunt , to buy me a tiny amount of space,  as it is the Up platform is length limited and I dont like it because of that ( 7 feet, which isn't a lot in O Gauge ) but any extension to the Up platform has to come from the left of the picture and directly extends the baseboard , which is now at 32'6".  

Edited December 31, 2017 by Junctionmad

[Junctionmad]

 

 

 if feasible, to copy the layout at Badminton where those sidings are fed directly off the Up Loop extension (headshunt in your case) thus obviating the need for  the two catch points and using the revised connection towards the sidings for that purpose?

well this is about as much is feasible , not sure its adds much , technically it allows the yard to be shunted from the headhunt without disturbing the bay  and might provide an opportunity for coal staithes or some other feature ?

 

in this situation , would the goods exit signal have a co located disc to read into the headhunt ? You ( stationmaster)  have  suggested  place colocated discs , on the crossover as well , as in reality this was not a passenger accessible  siding , and I wonder if it really warranted a full running signal ? on this model layout )

 

Did the GWR place such disc up on a separate doll on a  bracket  ?

 

( tracks not all rejoined , and discs and trap points omitted ) 

 

 

Did the GWR place such disc up on a separate doll on a  bracket  ? ( this is meant to be late GWR early WR )

ie ,  would this be a better substitute to indicate access to the headhunt 

Edited December 31, 2017 by Junctionmad

[The Stationmaster]

well this is about as much is feasible , not sure its adds much , technically it allows the yard to be shunted from the headhunt without disturbing the bay  and might provide an opportunity for coal staithes or some other feature ?

 

in this situation , would the goods exit signal have a co located disc to read into the headhunt ? You ( stationmaster)  have  suggested  place colocated discs , on the crossover as well , as in reality this was not a passenger accessible  siding , and I wonder if it really warranted a full running signal ? on this model layout )

 

Did the GWR place such disc up on a separate doll on a  bracket  ?

 

( tracks not all rejoined , and discs and trap points omitted ) 

Screenshot 2017-12-31 21.55.07.png

 

 

Did the GWR place such disc up on a separate doll on a  bracket  ? ( this is meant to be late GWR early WR )

ie ,  would this be a better substitute to indicate access to the headhunt 

Screenshot 2017-12-31 22.30.22.png

 

If we're late GWR and adopt the layout change shown in this post the signal reading out of the goods yard sidings would almost certainly be a ground disc (as it was for the dock siding at both Badminton and Chipping Sodbury - I somewhere have the photo I took of that very signal at Badminton, GWR 1911 pattern half disc),  If you wanted to carry on with the siding signal (ring on the arm) ideally it ought to be one with two arms (one above the other) but a single arm equivalent probably existed somewhere or other on the GWR.

 

Placing of discs on a separate bracket did happen in GWR times but became far more widespread in the BR era.  In your time period you really have a choice of all sorts of earlier configurations as many survived into the 1950s including a few which had become obsolete but the 19320s (and there was even example of a long obsolete pattern being reproduced on a brand new signal in the mid 1950s which would in fact be ideal for your splitting signal where the headshunt leads off the crossover to the Up Main Line - there is an example in Post 78 in this thread, third photo down albeit on an older signal post)

 

 

http://www.rmweb.co.uk/community/index.php?/topic/48504-gwr-signals-and-where-they-go/page-4

 

Have a look also at the fifth photo down which would suit precisely the situation coming out of the goods yard if you use the loop arrangement. (a 1964 photo of something which was obsolete around 40 years earlier)

[Junctionmad]

If we're late GWR and adopt the layout change shown in this post the signal reading out of the goods yard sidings would almost certainly be a ground disc (as it was for the dock siding at both Badminton and Chipping Sodbury - I somewhere have the photo I took of that very signal at Badminton, GWR 1911 pattern half disc),  If you wanted to carry on with the siding signal (ring on the arm) ideally it ought to be one with two arms (one above the other) but a single arm equivalent probably existed somewhere or other on the GWR.

 

Placing of discs on a separate bracket did happen in GWR times but became far more widespread in the BR era.  In your time period you really have a choice of all sorts of earlier configurations as many survived into the 1950s including a few which had become obsolete but the 19320s (and there was even example of a long obsolete pattern being reproduced on a brand new signal in the mid 1950s which would in fact be ideal for your splitting signal where the headshunt leads off the crossover to the Up Main Line - there is an example in Post 78 in this thread, third photo down albeit on an older signal post)

 

 

http://www.rmweb.co.uk/community/index.php?/topic/48504-gwr-signals-and-where-they-go/page-4

 

Have a look also at the fifth photo down which would suit precisely the situation coming out of the goods yard if you use the loop arrangement. (a 1964 photo of something which was obsolete around 40 years earlier)

Thanks stationmaster , it would make an interesting signal

 

Next question , how would you signal the crossover on the Up loop to headshunt , minature arm , minature arm wth ring , disc etc

[The Stationmaster]

Thanks stationmaster , it would make an interesting signal

 

Next question , how would you signal the crossover on the Up loop to headshunt , minature arm , minature arm wth ring , disc etc

 

Use the one in the third photo down as linked above or the more modern method I mention in the caption.  Do not put a ring on the arm (one of the most common errors among modellers - rings were only put on the arm of signals which applied to sidings/goods lines and not on signals reading to such lines (that was a Southern thing).

[Junctionmad]

Use the one in the third photo down as linked above or the more modern method I mention in the caption.  Do not put a ring on the arm (one of the most common errors among modellers - rings were only put on the arm of signals which applied to sidings/goods lines and not on signals reading to such lines (that was a Southern thing).

 

thanks, I'm all clear now 

 

 

 

it could also be done using a disc instead of a semaphore arm depending on the purpose of the movement and subsequently it would almost certainly have been done using a co-located disc.

are there any pics of a typical co-located disc, was it at the foot of the post or mounted up high or on a bracket typically 

Edited January 2, 2018 by Junctionmad