NIK

5 minutes ago, kintbury jon said:

Hornby SWT 4vep on eBay.  Has a 20% off code that makes it a decent price.  Two left at time of posting.

 

https://www.ebay.co.uk/itm/315126519044?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=90j_qsyqqlo&sssrc=4429486&ssuid=nWwfM6fYQfq&var=&widget_ver=artemis&media=COPY

Hi,

Excuse my ignorance but how do you get 20% off?.

Hi All,

Note when I bought a SWT 4 VEP from Kernow and selected Royal Mail I was charged £15 for postage.

Regards

Nik

UK News:

After a macaque monkey escapes from a Scottish zoo and heads into Highland village locals are warned to look out for anything red faced and with a liking for alcohol - could be either the monkey or the zoo staff.

Hi,

Beggarwood is largely down for an extended period while another club layout has its wiring completed in time for our exhibition on the 9th and 10th March.

The SR C-C booster loco was tried out on a few tracks and the jury is out on whether the large wheel slop causes problems on the layout. I noticed one coupling was drooping and that may have caused a tendency to derail. Once derailed  it had a tendency not to re-rail itself on trailing points but that may be due to our third rail which is in the process of being lowered.

The loco has not been timed yet to see if its fast enough for passenger trains.

One of the revised Hornby 4 VEPs in SWT livery has been ordered for evaluation of the cab ends, roof ventilators and the chassis.

Our open days are a free for all stock wise so hopefully the new VEP once DCC'd will get a run out at out next open day on the 7th April. I might try and sneak the Jaffa Cake 4 CEP into a carriage siding.

If we get enough funds and a following wind the layouts may be in our new club hut.

More scenery is being added neat the tracks and could encroach on signal sight lines and signal locations so we need to get signal positions finalised. We have a signalling engineer in our club so we need to run the finalised plan past him.

We now have a Just Giving link on our BNHMRS website for fitting out our new hut, so any donations  would be gratefully received.

Nik (on behalf of Basingstoke and North Hants Model Railway Society - still looking for members)

Hi,

If you search the web for Dapol Imperium Decoder Manual you should find what you need fairly quickly.

Regards

Nik

Hi,

If the trailer bogies have pin point axles have Hornby reduced the depth of the wheel flanges?.

Regards

Nik

Hi,

I think when Hornby went on from the 2 BIL to the 2 HAL they added extra weight to the motor coach and I think that improved the smoothness of the running (motor under more load ).

Regards

Nik

Hi,

It looks like the motor is being described as 3 pole skew wound instead of 5 pole skew wound for the pre 2024 versions.

Regards

Nick

Hi,

I've thought about the idea of a twin electrically conductive magnet pair based coupling to replace the Bachmann ones.

A thing to check is can there be enough pull with two small magnets as opposed to one large one on a Hunt magnetic coupling?.

The other thing is attaching wires to the magnets without going near the curie temperature of the magnets and damaging them. Perhaps small wires can be quickly soldered to the Nickel housing of the magnets so the magnets don't get too hot.

I bought some small powerful magnets with wires attached many moons ago but I haven't seen them for sale since then.

Regards

Nick

Hi,

Your photo doesn't show what the wires coming out of the decoder to the left are connected to.

What are they connected to?.

Normally if the decoder is connected only to the decoder tester I would not expect the polarity of the DCC input to the tester to matter.

The motor running at full speed is often a symptom of the decoder being in DC compatibility mode and mistaking DCC for DC.

Regards

Nick

Hi,

There are some stay alive circuits that charge the capacitors to a lower voltage than the typical track voltage and then step up the voltage to that the decoder requires when there is a pickup problem between track and loco.

This could be done so that large capacity supercapacitors can be used which inherently have a low maximum voltage. These type of circuits tend to be more expensive.

The Hornby HM7000 series power pack is probably of this type (the step up is probably done on the decoder).

If loco decoders have Back EMF feedback operating and working well it is possible for low voltages at the track to be disguised until a DCC speed step is requested by the operator that is high enough that the motor cannot make the loco/train go faster as it simply isn't being supplied with enough voltage.

Maybe I will make a DCC track voltage monitoring vehicle (with radio link for the voltage data to be towed behind a loco).

Easier would be a power resistor connected by wires to crocodile clips clipped to the track and then a DCC voltage meter in parallel.

The resistance value would be that to take the max current the power district is rated for without tripping. If the voltage is <7V then that part of the layout may be out of spec for HO. If the voltage is <13.4 Volts then locos will not be able to achieve the max speed they would do on 12V DC (pre decoder fitting).

Regards

Nik

3 minutes ago, ATME said:

So does this mean that all decoders should work in the range 8.5v to 22v despite being informed by Accurascale that ESU v5 decoders require a minimum of 14v?

Hi,

The NMRA document says peak voltage decoder should operate in and withstand is 7 Volts to 27 Volts.

I assume the 7 volts is to allow for voltage drop due to resistance in the wiring and rails.

I assume the 27 volts is to allow for voltage spikes generated external to the command station.

I have yet to find anything in DCC decoder manuals about NMRA voltage compliance.

Regards

Nik

33 minutes ago, Bucoops said:

 

https://www.nmra.org/sites/default/files/standards/sandrp/pdf/s-9.1_electrical_standards_for_digital_command_control_2021.pdf

 

NMRA says nominal voltage for HO is 15v.

Nominal Voltage limit not nominal voltage.

Hi,

I think the bit about Accurascale coaches was they drew 30?ma for 20 seconds on so on DCC power up after a period with no power to the track. I guess the problem is 10 coaches makes 300ma draw and then there is the short startup current of the main capacitors of sound fitted locos and together they appear to have tripped 3 amp district cutouts on their layout (assuming all accessories and their  decoders are powered from a separate supply).

Many years ago for Beggarwood Lane, a 'large' OO DCC layout I did some calcs which included trains double headed by big Heljan diesels and concluded we could get away with a 5 Amp command station  and three power districts with 3A district cutouts (accessories and accessory electronics powered from a separate supply). The power districts were divided not by baseboard but by track so a train was unlikely to span two districts on DCC power up. Dividing a fiddle yard power districts by baseboard or baseboard groups has some merits if the layout is very big.

My calcs did not include coaches with lighting and Accurascale Mk1 coach stay alives since they were not around then. The calcs did not include the surge current of sound locos on DCC power up either.

Regards

Nik

Hi,

If the road is to represent one built today then it will be the width of one built today divided by 76.2.

Regards

Nick

Hi,

From the Hornby website:

Regards

Nik

Hi,

I think the latest photos for the two units announced show the motor moved to the brake end.

Or were you referring the older models?.

Regards

Nik

Hi RFS,

It would also have been nice if Dapol had written in the instructions which Function number of the DCC connector pins connected to which light.

I've found a quirk is that the loco now its got the MX634D decoder in it and its on DC and in reverse the interior cab light (No 1 end) comes on. 

Regards

Nick

17 hours ago, NIK said:

Hi,

 

I ordered a Blue JA from Kernow. Its due to arrive tomorrow so will check the wiring and the pickups when it arrives.

 

Regards

 

Nik

Hi,

4D-006-017 JA Class 73 OO just arrived. Seems to pick up fine at least on rolling road.

Seems to run fine on DCC on RR without stay alive. Still have to work out interior cab lights under DCC (Zimo MX 634D).

Seems to have proper warning yellow on ends rather than a hint of lime green. The battery box clips marked out in yellow unlike an earlier batch BR Blue JB.

Only one bit has fallen off so far (a bogie damper) and that was when taking the body off.

About 500ma at max DC so not a coreless motor.

Regards

Nik

Scientists who had announced they had cloned a monkey for research purposes now admit it was a Frenchman picked up in Hartlepool.

Hi,

I ordered a Blue JA from Kernow. Its due to arrive tomorrow so will check the wiring and the pickups when it arrives.

Regards

Nik

Hi,

Rails say they have coreless motors whereas Dapol say the OO Class 73 have the super creep motor but don't mention coreless.

Regards

Nick

Hi,

I thought those sold out two days ago.

Regards

Nick

8 minutes ago, John Besley said:

Can I jump on this topic, I am about to fit a Zimo economy MX600 ... this has a 8 pin board, the chassis I am wiring up to uses a HLK gearbox and C1230? can motor, soldering connections isn't a problem for me just want to know whether to solder direct to the pins and wrap this up as I don't have a 8 pin socket board to plug into.

 

Likewise where do I mount the stay alive across, I guess this would be wired on to the motor terminal as well

Hi,

If you have the space there are 8 pin breakout boards for decoders with NEM652 connections.

Regards

Nik

4 hours ago, Rich46 said:

Regarding changing the route discs/lights. I pushed them out using a small flat bladed screwdriver. Once they had moved slightly they came out easily. To get the replacements in I chamfered the end of each spline (used to locate them correctly) and slightly rounded the inner ends. This enabled me to locate them just in the hole followed by firm push home. So far I have fitted a Zimo standard decoder to the green CC1. It runs well except for one short length on my layout so I will investigate the bogies to see if the problem lies with them. 20002 in black/silver is awaiting the Youchoos sound decoder I have bought with a mix of their Class 71 and 2-BIL sounds. 20003 in post 1956 BR green will be fitted with a sound decoder later. 

Hi,

What's a Zimo standard decoder?.

Regards

Nik

Hi,

The initial launch was just for the loco decoders but accessory decoders are planned and the app already has a facility for accessory operation.

Regards

Nik