This the official reply from Hornby regarding my problem:
Hello Peter,
You are being replied to from .. snipped-for-privacy@hornby.com ...this is Hornby DCC Support
Did you email previously? Sorry I do not have any emails from you re the issue.
..
The following should clarify the situation..
Get back to me if you require further information.. etc
Kenn
HH DCC Support
R8236???
The SELECT =93walkabout=94 when used with the ELITE with the supplied cable (R8236) may occasionally suffer communications errors. This issue appeared after the initial trial were made. It is due to local electrical conditions within/external the cable. Also, it is important to connect walkabouts in the correct way.. it is not ideal to daisy chain walkabouts.. please see the diagram attached for more information.
The issue of communications errors was resolved by a new cable (R8266) this cable has a different configuration. I will send you a replacement cables.
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Hornby R8266.. this is a 3m 4 conductor cable.. the conductors are arranged in 2 pairs and DO NOT follow the standard pattern as used in RJ11/12 IT cables. See diagram below. The diagram is for illustration only and appears shows flat profile cable.. the R8266 actually uses a round profile cable.
You can extend this cable.. i.e. connect several together using the standard type end to end extender/adapter..
You can get these from Maplin Electronics (UK) and other electrical/IT stores.
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The XpressNet interface is based on the RS485 standard and should be good for up to 3000 feet !!
In practice I have checked the SELECT communication under ideal cable conditions for 100 feet.
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Some users make up their own cables.. using the configuration info above.
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-----Original Message----- From: snipped-for-privacy@aol.com [mailto: snipped-for-privacy@aol.com] Sent: 06 September 2010 09:54 To: Help DCC Subject: Form submission from your website: Customer Care
Enquiry Type:
Technical Support
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Your Name:
Peter ABRAHAM
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Your Email:
snipped-for-privacy@aol.com
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Membership Number (if applicable):
Not provided
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Message:
Ref HA 37626
Having brought in the hard of seeing kit I have discovered that both of my "4" wire cables R8266 are in fact 6 wire R8236. No matter, they work fine with two walkabout units as I had surmised. It being difficult to obtain these easily I picked up a new 6 wire RJ12 cable through my IT supplier. This cable is identical to the 8236 and each core shows continuity and is insulated from it's siblings!
The simple act of plugging it into the Elite unit stops all commands (but no fault condition). If it is also inserted into the walkabout then CE shows up followed by continuous flashing of the red lamp.
Is there something ridiculously banal which I have overlooked?