Fitting HM7000 21 pin decoder to Caerphilly Castle Loco R30328

[Bugsy1957]

Hi, I'm just wondering if anyone else has tried this combination? I'm having an issue with the physical fit of the board in that it is not secure and tilts up (see photo)

It's been suggested I cut away some of the fouling areas on the loco but with it being brand new I'm worried I won't make a good job of that and mess up the warranty

Is there such a thing as 21 Pin riser boards? I've googled but not found anything yet,

[Pendragon Sailing]

Could you try putting some ‘packing’ under the screws securing the 21 pin pcb?

[RDS]

@Bugsy

Why have you posted the same picture twice in different threads

[Bugsy1957]

Could you try putting some ‘packing’ under the screws securing the 21 pin pcb?

 

 

I am going to investigate this option as it seems "less drastic". If I get it to work I will update the thread so anyone else in the same position can benefit.

[Bugsy1957]

@Bugsy

Why have you posted the same picture twice in different threads

 

 

Because that was for the benefit of those who had assisted me trying to resolve the decoder programming issue but this was meant to be of help to those who may be considering the purchase of the loco and decoder. My apologies if it is seemed as a major issue but I genuinely had others in mind

[phil_dalton]

I have this same problem with R30272 Caldicot Castle. Although I believe that the problem is caused by the DCC Chip having to be installed upside down relative to other classes (e.g. LNER A4 or P2). The pins on the connector do not go far enough through the HM7000 chip to give a good grip and so the chip can wobble freely. Was this done deliberately due to the lack of vertical space inside the Churchward tender? If so, then this shows a complete lack of complete design thinking for GWR Castles with Churchward tenders.

[Bulleidboy]

Have you tried turning the decoder over? 21pin decoders should fit and work either way up. Be aware that some Hornby 21pin loco's have a different pin configuration.

[96RAF]

The famous decoder manual describes and illustrates the optional orientations for the 21-pin decoder.

[Simon-372339]

If you look in the Hornby 'shop' there is no mention of HM7k for this model. Just 21pin ready.

If the alternate orientation also doesn't fit...

If the screws are long and thin enough the inside from a biro snipped off with scissors may be a suitable riser.

If the screws are too short, 'Hello customer services...'

[Bulleidboy]

From the photograph it looks as though the decoder would fit properly if turned over?

[SteveM6]

Remove the tender weight? If necessary replace with something small by heavy held in with black tack .

[SteveM6]

Remove the tender weight? If necessary replace with something small by heavy held in with black tack .

[ColinB]

Well done Hornby this was the issue I had with my West Country but nowhere near as bad. The P2 21 pin socket PCB would probably fix it. Hornby realised their mistake and on the the P2 they changed the orientation of the board so it is upside down. In your case I suspect it will miss the weight. I am not an advocate of removing weights the designer put them there for a reason. Anyway if you ever want to sell it on it is no longer mint and you can't buy the tender weight as a separate part. I suggest talking to Hornby technical. That socket I think is for the Powerbank which you will probably need, so you can't even remove it. Trouble is from what I remember Castle tenders don't have much headroom so lifting the board up may be an issue.

[Going Spare]

Contact technicalservices.uk@hornby.com.

[phil_dalton]

I have spent some time reviewing the relevance or not to previous responses to this problem and my findings are as follows:

• You can not flip a 21pin chip over as the 21 pins are aligned with one row containing 11 pins and the other 10. I.e. there is a blank at the end of the row of 10. To flip the chip over would cause a pcb pin to hit the blank on the chip.
• Having read V1.3 of the decoder manual the PCB for the GWR Churchward tender allows a TXS chip to be attached in what Hornby call the "compact" position. Models with larger tenders, e.g. Gresley P2 or A4, the fitted PCB requires the TXS chip to be inverted or in Hornby speak "rotated". So it is the PCB fitted to the model that determines which way up the chip has to be installed.
• I did try removing the weight in the tender, but discovered that this did not impede the fitting of the chip in any way.
• My conclusion is that the pins on the PCB are too short to adequately support a chip the size of a sound TXS chip.
• I will be contacting technical support at Hornby about this problem

Finally, I would just like to refer the response that there is no Sound profile announced. Whilst true, one has been announced for a GWR King. In a previous forum entry of mine I questioned as to why there was no TTS chip for a GWR Castle, when there was one for a GWR King. The responses I received I took to mean that I was being pedantic as the 1:1 scale wheel size of 6ft 8.5in versus 6ft 6in amounts to less than 1mm when reduced to OO scale and they are both 4 cylinder classes. However, in the past Hornby did produce BR Castle 7029 "Clun Castle" with sound provided by a Loksound V4 chip (although actually recorded on GWR Castle 5043 "Earl of Mount Edgcumbe" on a run to Salisbury). Is it too much to ask for the sound files to be remastered to a TXS sound profile?

[LTSR_NSE]

@phil - might any of the following suggestions assist?:

• look to see if a male-to-female 21pin spacer exists - to effectively raise the height to accommodate decoder.

• remove screws attaching PCB to tender chassis, but use spacers/washers & longer screws to reattach it in a higher position allowing decoder to be properly attached.

• remove PCB, attach decoder to PCB, wrap PCB+decoder in either kapton tape or loose fitted shrink-wrap - to prevent ‘floating’ circuitry touching metal.

•completely dismantle tender chassis & modify it to enable decoder to fit.

Not wishing to imply that above are/aren’t reasonable or should/shouldn’t be necessary - only wish to offer possibilities.

Regarding sounds, Hornby devs have said that remastering of older samples/recordings is probably a non-starter due to their fidelity.

Naturally TXS profiles are being produced for any locos that a sound-fitted variant is/will be available (and several that aren’t!) - considering a TT:120 Castle is/will be in development, it is extremely probable that a TXS profile will also be produced at some point.

[ColinB]

Perhaps the easiest solution is to replace the 21 pin socket with an 8 pin. likewise with the HM7000. Normally I wouldn't suggest such a thing but it might just give you sufficient room. Alternatively put the HM7000 into another loco and buy an alternative sound decoder that will fit. To me they seem the only two alternatives. I must admit I find it surprising that sound profiles that existed on TTS are not replicated on HM7000, whether it involves getting new recordings or not. I also find it surprising that Hornby don't class sounds for the current range of locos above others. I recently was looking for sound for an 8F, in the end I bought one from a competitor.

[Daedalus]

You can get this 24 pln header, if you can wait for it coming from china, although in my experience they arrive in about 1/2 the time.

It is 1.27 mm which I think is the correct pitch.

https://www.ebay.co.uk/itm/403328753364

P.S. If you want round pins. You could use a 5 pin and 6 pin.

https://www.aliexpress.com/item/1005006112674330.html?spm=a2g0o.detail.pcDetailBottomMoreOtherSeller.37.4aba0mom0momRD&gps-id=pcDetailBottomMoreOtherSeller&scm=1007.40000.326746.0&scm_id=1007.40000.326746.0&scm-url=1007.40000.326746.0&pvid=c3e754cc-b41e-475e-b9f1-91288ef1fb1e&_t=gps-id:pcDetailBottomMoreOtherSeller,scm-url:1007.40000.326746.0,pvid:c3e754cc-b41e-475e-b9f1-91288ef1fb1e,tpp_buckets:668%2328

There are plenty more on aliexpress. N.B You will be charged VAT since Brexit.