Occasionally I'm getting a new kind of interference with strong 33 Hz spaced lines all over the LF band. Variable RDF colour indicates that it could be emitted from power converters on moving railway
I seem to recall that some railway systems use at about 16 2/3 Hz (one third of 50 Hz) for traction. Historically, some systems used about 33 Hz. I read somewhere that on-board power converters on so
Railway QRG is 16 2/3 Hz in Sweden too. 73 de Johan SM6LKM John Rabson wrote: I seem to recall that some railway systems use at about 16 2/3 Hz (one third of 50 Hz) for traction. ... Can someone say
Is that to minimise skin loss in steel track ? UK Third rail is, of course, DC, and I once spent an idle moment calculating the loss if 50Hz AC were to be used with magnetic iron conductors. I think
Hi, 16 2/3 Hz was used as it enables the older brush motors to have much less losses than if they were run at 50 Hz -they would behave much more as if DC was applied (easier to handle). However 50 Hz
Hello John, Johan, LF 16 2/3 Hz should probably be 16 1/3 Hz, one third of 50 Hz as John pointed out. Here in OH-land we use 50 Hz for the railways but during my EE studies, the SM-land railway QRG w
I suppose 16 2/3 is correct (16 1/3 x 3 = 49), according to my information, they actually use 16.7 in some places these days. 73 Ulrich PA7EY 2016-03-17 15:59 GMT+01:00 <[email protected]>: Hello John,
The 16 2/3 Hz trace is visible on my VLF remote grabber at http://www.iup.uni-heidelberg.de/schaefer_vlf/DK7FC_VLF_Grabber2.html About 35 dB SNR in 3.8 mHz, to be improved. Although the voltage for t
That problem can be solved by using a return line and booster transformers that minimises current leakage into surrounding earth: https://library.e.abb.com/public/f1200714de5086c585257d7300287357/1LF
Hi, A very interesting article. The London Underground (Metro) uses a low voltage 4 rail DC system. The 2 'live rails are balanced + and - with regard to the running rails. This system is a 'throw-ba
Johan, Many thanks for the reference. I now understand much better how these things are arranged. 73 John F5VLF [email protected] Researching history of RABSON, BLACKSHAW, GAUNTLETT, VERLANDER
