RMweb Premium uax6 Posted November 20, 2023 RMweb Premium Share Posted November 20, 2023 On 17/10/2023 at 20:36, D7063 said: Sprayed Limpet Asbestos anyone? From a time when asbestos was a ubiquitous wonder material :( This advert actually shows something that few people actually know, that is that there is fibreglass out there that is heavily contaminated with asbestos. I've got the LTC Rolt book on Turners Asbestos (It was published without his name on it), and it shows the development of fibreglass by Turners using asbestos as a filler medium, or as the main strength component. I wouldn't be surprised if a lot of fibreglass boats, cars, and surfaces from the late '50s and '60s aren't actually made with Roberts/Turners asbestos.... Andy G 2 4 Link to post Share on other sites More sharing options...
RMweb Gold Bucoops Posted November 20, 2023 RMweb Gold Share Posted November 20, 2023 19 minutes ago, uax6 said: This advert actually shows something that few people actually know, that is that there is fibreglass out there that is heavily contaminated with asbestos. I've got the LTC Rolt book on Turners Asbestos (It was published without his name on it), and it shows the development of fibreglass by Turners using asbestos as a filler medium, or as the main strength component. I wouldn't be surprised if a lot of fibreglass boats, cars, and surfaces from the late '50s and '60s aren't actually made with Roberts/Turners asbestos.... Andy G Yup, always fun to find that one. Fortunately it's quite well bonded in so unless someone attacks it with a saw (which still happens...) it's relatively low risk. 2 Link to post Share on other sites More sharing options...
RMweb Premium figworthy Posted November 20, 2023 RMweb Premium Share Posted November 20, 2023 10 hours ago, Bucoops said: Yup, always fun to find that one. Fortunately it's quite well bonded in so unless someone attacks it with a saw (which still happens...) it's relatively low risk. I have vague recollection from the mid 70s of glass fibre (the raw material) and Turners in the same context, in which case it is quite possible that there are people out there who handled the raw material at home when making "stuff". Adrian 1 Link to post Share on other sites More sharing options...
RMweb Gold Bucoops Posted November 21, 2023 RMweb Gold Share Posted November 21, 2023 12 hours ago, figworthy said: I have vague recollection from the mid 70s of glass fibre (the raw material) and Turners in the same context, in which case it is quite possible that there are people out there who handled the raw material at home when making "stuff". Adrian No doubt about it sadly. I am referring its current state though. Link to post Share on other sites More sharing options...
D7063 Posted November 25, 2023 Author Share Posted November 25, 2023 Good morning all! A nice little shunter from Yorkshire :) 9 Link to post Share on other sites More sharing options...
D7063 Posted January 5 Author Share Posted January 5 Hasler Telegraph Works this evening, manufacturers of the finest Speedo's!!!!! 3 Link to post Share on other sites More sharing options...
D7063 Posted January 7 Author Share Posted January 7 I found the case study of Dover Marine quite interesting, it was closed in 1994 and the section shown must have been outside the main 'Overall Roof'. The site is now a terminal for cruise liners, I imagine there is no trace left of the 'Unilux' roofing :( 6 Link to post Share on other sites More sharing options...
RMweb Gold Bucoops Posted January 7 RMweb Gold Share Posted January 7 Interesting - wonder if they were linked to the company that produced asbestos insulating board "asbestolux"- then the non-asbestos "supalux" version. 1 Link to post Share on other sites More sharing options...
RMweb Premium uax6 Posted January 7 RMweb Premium Share Posted January 7 38 minutes ago, Bucoops said: Interesting - wonder if they were linked to the company that produced asbestos insulating board "asbestolux"- then the non-asbestos "supalux" version. Asbestolux and supalux were both Cape Asbestos products. UAM plastics doesn't come up in a google search... Andy G 2 Link to post Share on other sites More sharing options...
RMweb Premium kevinlms Posted January 7 RMweb Premium Share Posted January 7 Now was that the roof that Tri-ang used as their prototype? Simplified of course. https://tri-angman.co.uk/product/tri-ang-Hornby-r585-station-platform-with-canopy-fence-and-brown-seat-unit-perfect-condition/ 2 Link to post Share on other sites More sharing options...
D7063 Posted January 12 Author Share Posted January 12 106 channels is pretty impressive for the time, as is the stylised Hymek!!!!! Seriously though the resonance of 'tuned reeds' sounds a bit fragile to me - how robust was it in actual service, does anyone know? 5 1 Link to post Share on other sites More sharing options...
D7063 Posted January 12 Author Share Posted January 12 Just now, D7063 said: 106 channels is pretty impressive for the time, as is the stylised Hymek!!!!! Seriously though the resonance of 'tuned reeds' sounds a bit fragile to me - how robust was it in actual service, does anyone know? Actually, looking again, I think there is a dash of 'Falcon' in that 'Hymek' :) 2 Link to post Share on other sites More sharing options...
MartinRS Posted January 12 Share Posted January 12 53 minutes ago, D7063 said: 106 channels is pretty impressive for the time, as is the stylised Hymek!!!!! Seriously though the resonance of 'tuned reeds' sounds a bit fragile to me - how robust was it in actual service, does anyone know? I remember being shown the reed once when I visited Sheffield Power Box in the 1970s. It was housed in a perspex box and was regarded with something approaching awe. I was working in the telecoms department of the local S&T department at the time which covered both Sheffield No. 1 district (still called the Midland side) and Sheffield No. 2 district (which was always called the Great Central side). I can't comment on how reliable the reed was, as its system covered the Midland main-line and I spent most of my time working on the Woodhead route. I never heard of any problems though. I think it provided a clock signal for some sort of a TDM system? 1 1 Link to post Share on other sites More sharing options...
D7063 Posted January 12 Author Share Posted January 12 25 minutes ago, MartinRS said: I remember being shown the reed once when I visited Sheffield Power Box in the 1970s. It was housed in a perspex box and was regarded with something approaching awe. I was working in the telecoms department of the local S&T department at the time which covered both Sheffield No. 1 district (still called the Midland side) and Sheffield No. 2 district (which was always called the Great Central side). I can't comment on how reliable the reed was, as its system covered the Midland main-line and I spent most of my time working on the Woodhead route. I never heard of any problems though. I think it provided a clock signal for some sort of a TDM system? Yes, that's how I was imagining it in terms of a 'clock' signal being generated by the reed. Although I'm now also thinking of it in a glowing perspex box like the central control column of the Tardis!!! 2 Link to post Share on other sites More sharing options...
BernardTPM Posted January 13 Share Posted January 13 (edited) 3 hours ago, D7063 said: Actually, looking again, I think there is a dash of 'Falcon' in that 'Hymek' :) It's Lion (it even has the unusual nameplate and is numbered D0260); AEI were part of the consortium that built it. Edited January 13 by BernardTPM 1 1 Link to post Share on other sites More sharing options...
Grovenor Posted January 13 Share Posted January 13 The tuned reed system was FDM, not TDM. Every one of the 106 channels required a transmitter reed unit and a reciever reed unit, I think the channels were 3Hz apart. There was also a related reed track circuit system which had a much restricted range of frequencies as it had to avoid any frequency that might be produced by a traction package working on the line. 2 Link to post Share on other sites More sharing options...
MartinRS Posted January 13 Share Posted January 13 Hi, Thanks for the information. I had very little involvement with Sheffield No.1 signalling division (ex MR). They used the reed system and Astra-track (or a similar name). I think Sheffield No.1 also used standard 50v DC track circuits on some lines still with traditional signal boxes. On Sheffield No.2 division (ex GCR) it was AC track circuits on most running lines because of the need to (impedance) bond rails for the Class 76 1.5kV DC locos on gradients (which was most of the trans-Pennine Woodhead route) to provide an adequate return for the traction current. Roads fed by the hump at Tinsley Yard, being for freight wagons only, used rail circuits. NB. Wikipedia makes no distinction between track circuits and rail circuits though they are two different things in my limited employment experience on BR. 7 hours ago, Grovenor said: The tuned reed system was FDM, not TDM. Every one of the 106 channels required a transmitter reed unit and a reciever reed unit, I think the channels were 3Hz apart. There was also a related reed track circuit system which had a much restricted range of frequencies as it had to avoid any frequency that might be produced by a traction package working on the line. Do you mean 3kHz? 1 Link to post Share on other sites More sharing options...
Grovenor Posted January 13 Share Posted January 13 2 hours ago, MartinRS said: Do you mean 3kHz? No, I meant 3Hz. Not sure of the frequency range now but I think it was in the region of 300 to 600Hz. £Hz spacing would need 318Hz bandwidth. The Track circuits were around the 300Hz mark and had to avoid all the harmonics of 50Hz plus or minus a bit. The tuned reeds had a very tight resonance frequency which allowed for the close channel spacing. Mostly this is from memory as I no longer have my reference material. 1 2 Link to post Share on other sites More sharing options...
Grovenor Posted January 13 Share Posted January 13 Googling found this paragraph for me from an Irish railway standard, so maybe I'm 1Hz out. 🙂 Quote The transmitter and receiver in the reed FDM system consist of a reed filter and an amplifier. The reed filter is a high-q band-pass filter, which passes only the frequency allocated to the particular channel and excludes all others with a nominal bandwidth of ±0.5 Hz. The selectivity of the reed filters is such that the system can be operated with frequencies as close as 4 Hz; hence a very large number of channels can be accommodated within a small range of frequencies. It also came up with this video, 1 3 Link to post Share on other sites More sharing options...
D7063 Posted January 14 Author Share Posted January 14 21 hours ago, Grovenor said: Googling found this paragraph for me from an Irish railway standard, so maybe I'm 1Hz out. 🙂 It also came up with this video, Well I gave that video a 'like' on you tube - we've probably increased the viewing numbers a bit too! Link to post Share on other sites More sharing options...
D7063 Posted January 14 Author Share Posted January 14 Continuing along a similar theme we have some nice screened cable from BICC 🙂 4 Link to post Share on other sites More sharing options...
RMweb Gold SHMD Posted January 14 RMweb Gold Share Posted January 14 Now I remember BICC! Kev. 1 1 Link to post Share on other sites More sharing options...
D7063 Posted January 15 Author Share Posted January 15 Staying on the comms theme, and not a stylised Deltic in site!!!! A little something for all the S&T fans out there 🙂 7 Link to post Share on other sites More sharing options...
Nearholmer Posted January 15 Share Posted January 15 Here’s a really interesting bit of rather earlier S&T kit, which begins to get you into primitive FDM. This articles, from which I lifted the advert, gives some of the background and the other day I found a far better article about these early systems. If I can find it again, I will give another link. http://www.samhallas.co.uk/railway/phonopore.htm 8 Link to post Share on other sites More sharing options...
D7063 Posted January 15 Author Share Posted January 15 1 hour ago, Nearholmer said: Here’s a really interesting bit of rather earlier S&T kit, which begins to get you into primitive FDM. This articles, from which I lifted the advert, gives some of the background and the other day I found a far better article about these early systems. If I can find it again, I will give another link. http://www.samhallas.co.uk/railway/phonopore.htm Hey, that was an interesting read that sent me down a bit of a rabbit hole. I'm amazed that these circuits could maintain a stable frequency with the primitive components available - I wonder how they would have calibrated them, I'm guessing this was before the days of oscilloscopes? 1 Link to post Share on other sites More sharing options...
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