Rochford Castle Posted November 19, 2020 Share Posted November 19, 2020 I have been collecting model rail stuff for years, but I am only now getting round to doing my first layout.I am trying to fit the appropriate TTS sound chip to R3237 Caerphilly Castle, and the tender seems to be too small. My options seem to be to melt away part of the frame underneath the artificial coal or replace the speaker. If I go down the latter route, what sort of wire should I get? What size of speaker, and what are the specifics with regard to "sealing" the speaker?Also, should I be covering the actual chip with gaffer tape? Link to comment Share on other sites More sharing options...
ColinB Posted November 19, 2020 Share Posted November 19, 2020 The easy solution is buy a different speaker. I use the small "iphone" speakers that a guy on EBay sells, they are incredibly thin and seem to fit in most locos. Alternatively, use a small "Sugar Cube" speaker that will definitely fit. I hate to see people hack the plastic around to make stuff fit, it generally weakens the model. The wire I use I think is 7/0.1 wire or something near it. It is small enough too fit and reasonably flexible. I bought some wide clear heat shrink to put the decoder in, but I don't shrink it. With these decoders heat is an issue, so they need a free passage of air across them. The top side is more critical than the underneath. Gaffer tape is not a good idea, even Sellotape which Hornby recommend doesn't seem that great either. Link to comment Share on other sites More sharing options...
Lyd 85B Posted November 19, 2020 Share Posted November 19, 2020 I fitted the R8110 TTS decoder to my R3118 'Penrice Castle' without difficulty but, assuming that 'Caerphilly Castle' has a similar tender configuration to that shown in Service Sheet HSS 346C, you will need to detach the black plastic surround from the speaker to get it to fit in the tender housing, under the metal weight. The speaker needs to be fitted with the wiring uppermost and there is enough room for the decoder to fit above it. Link to comment Share on other sites More sharing options...
96RAF Posted November 19, 2020 Share Posted November 19, 2020 Gaffer tape is a good idea but only if you use it to insulate the metal parts of the loco or tender. Do not stick it to the decoder. Replacing the speaker with a smaller sized one is OK and does not void the TTS warranty, but make sure it is capable of handling 1 Watt and has an impedence of 8-ohms. Some of the speakers sold by Richard Croft of Road and Rails (likely to be the eBay and FB seller that Colin keeps dancing round) are only 4-ohms for use with newer ESU decoders. You also may find 100-ohm speakers but these are becoming rare and only used on old v3.5 ESU decoders. When changing a speaker desolder at the existing speaker and extend wires as necessary to the tender. It is not recommended that you desolder at the decoder end. I tape my speakers tomthenbench as thenmagnet can grab your hot soldering iron tip and ruin your speaker. Sealing - you need to seal the speaker front side from the back side. This simply involves a sliver of glue or tak substance around the rim and wires where they sit in the enclosure. This gives you,an idea of what we are aiming for.../media/tinymce_upload/35d640060335af674b7b7e32ce95a67e.GIF Link to comment Share on other sites More sharing options...
96RAF Posted November 19, 2020 Share Posted November 19, 2020 This shows a poor speaker installation, where there is no simple enclosure possible so any sealing has to be ’tak’ sealer as best as possible. the chassis floor is acting as the main isolation baffle. Not shown is the gaffer tape stuck across that metal weight to insulate the decoder. /media/tinymce_upload/51958eedd8b00f43411f60b6de3fd4de.JPG /media/tinymce_upload/1b33dcee143b1aca16da3701fdd06212.JPG Link to comment Share on other sites More sharing options...
ColinB Posted November 19, 2020 Share Posted November 19, 2020 The majority of the speakers than Richard Croft sells are 8 ohm. Generally as with a lot of the 4 ohm speakers, he does a package which is two 8 ohms in parallel, YouChoos do the same. The only true 4 ohm I have seen was rectangular one that comes with the Loksound sound decoder, it was fitted to a Bachmann loco I bought secondhand. All the iphone ones are 8 ohm, as are virtually all the sugar cube ones. Generally you can tell anyway if the speaker is rated at more than 1 watt then they are 4 ohm. The 4 ohm speaker that I have seen on Richards Croft's EBay account wouldn't fit anyway, they are too big. I must admit I fit iphone speakers where ever I can, the sound quality is excellent, they are super thin and very easy to insulate. Other than the two connections there is nothing metal to touch, unlike a sugar cube speaker.That photo is exactly how Hornby expect you to fit the speaker, that looks like a Duchess setup. It was like that in my factory fitted one. The thing that annoys me is if you analyse the tender weight, it is under stress, it should fit horizontally, but because it doesn't fit properly it is putting stress on the screws that hold it down. Link to comment Share on other sites More sharing options...
Fishmanoz Posted November 19, 2020 Share Posted November 19, 2020 Am I missing something here? Speaker needs to be 8 ohm, not 4 ohm. Rob, I hope you mean your 4 ohm ESUs are in series not parallel? Link to comment Share on other sites More sharing options...
96RAF Posted November 20, 2020 Share Posted November 20, 2020 Correction made Fishy and original post hidden... Apologies for hi-jacking the thread but these are all examples of speaker installations to help the OP.2 x 4-ohm ESU speakers in enclosures wired in series to give 8-ohm. Superb sound in a Class 31.Decoder is loose sleeved per Colins earlier comment.Tak was used to seal the wire slots../media/tinymce_upload/32ba3c8702f3061ef639b6f82031abe5.JPG Link to comment Share on other sites More sharing options...
ColinB Posted November 20, 2020 Share Posted November 20, 2020 I did wonder, but I thought I would let it go. I will stick to my iphone 8 ohm ones. The iphone is a "horn" type speaker so it lacks bass, but given the amount of room available generally there isn't enough room to put a decent bass speaker with a decent enclosure in. Link to comment Share on other sites More sharing options...
96RAF Posted November 20, 2020 Share Posted November 20, 2020 Am I missing something here? Speaker needs to be 8 ohm, not 4 ohm. Rob, I hope you mean your 4 ohm ESUs are in series not parallel?You are correct Fishy - typo - corrected above. Link to comment Share on other sites More sharing options...
OssieB Posted November 20, 2020 Share Posted November 20, 2020 @Rochford CastleI have fitted a TTS decoder to my Caerphilly Castle with the small 3500gal tender. I found it necessary to cut away the inside of the body below the coal load to accomodate the decoder as there was not enough clearance above the weight housing the standard speaker. In my case I had already decided that I was going to use a sugar cube speaker for better sound quality, and this cutaway aloud me to fit the speaker below the coal load. In the photo, when enlarged, you can just see the extent of the cutaway. You can see that I have sealed around the edges of the coal load with blue tak, and this considerably enhances the sound quality. The sugar cube speaker size is 20mmx15mmx10mm. I insulated the decoder with a loose sleeve of heat shrink. /media/tinymce_upload/ac6d0c271009f8376757cf3daa1f3bf1.JPG.I hope this of some help for you in fitting your TTS. BarryO Link to comment Share on other sites More sharing options...
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