Hi Tracey I have a house full of Low Energy lamps, of various manufacture, Ring, GEC, Osram, Philips, Ikea, and not noticed any problems with noise on VLF. Where the ballast is built into the lamp, t
Hello Andy I think I've answered my own question here. I built the filter and it doesn't work with 50 ohm input/output impedance, but it DOES work with 50k ohms. Narrow isn't it ! I can just about hi
Hello Andy, In your recent posting about the 33kHz crystal filter, can you clarify what the characteristic impedance is ... It is very unusual to specify an impedance in terms of a frequency, so I fe
I discovered a length of aluminium tube in the garden, being used to grow runner beans. I snatched it from its surroundings and It now enjoys a better existence as part of a VHF antenna. It sees the
Thanks Peter, I Will "listen" out for you at 1600 UTC I have now worked out where I am on the band, and have Argo working with the output from the Siemens D2006. 73 Hugh M0WYE I hope to be on 71.6+kH
Hi Alan, Thankyou for your comments. Tomoro night night is natter night at the club, I'll see if anyone knows of any local operators on 73kHz. Otherwise I shall concentrate on RX and try and get some
Hello John, Thanks for your reply, John. Shame about the NOV's - it is probably best for a newcomer to concentrate on 136 anyway - looking to the longer term. I have a 100W Mosfet amp with a 3dB freq
Hi all, Does anyone know if the RA is still issuing NOV's to use the 73kHz band ? I realise that it ceases to be available after June next year, but there are still a few months yet ... The reason I
Hi Thanks for the warning about the "virus" file. I have the extensions turned on in the folder options, so things like this show up better. If you have them hidden it looks just like a .doc file. I
Hi Laurie, "Wire in the air has 100 times more worth than wire in the air " There I've said it again sorry. Don't be sorry, Steve is not the only one currently winding coils and contemplating top and
Thankyou Johan, Rik, Stewart, Alan, Dave, Alex and others, for giving me your thoughts. I like Dave's "quick and dirty" way, which is basically what started out by doing, except that I relied on the
Hi All, I built the little antenna current meter shown in the LF Experimenters Handbook last night (Page 81). And it works. I measured the current from my HF rig into a dummy load at 1.8MHz, and it g
or a 3/4 wavelength ... Or - you could spin the loop really fast. (with slip rings for the signal) For VHF DF they switch rapidly between four quarter-wave whips arranged in a square, which gives a s
What an intriguing circuit - I read up on the "Spontaflex" on this web site: http://www.spontaflex.freeserve.co.uk/autoflex/autoflexpage1.jpg I had not heard of it before. I wonder how you demodulate
Hello Jan-Martin, How big is your frame antenna ? 73 Hugh M0WYE Hi still experimenting with frame antenna for 136kHz. The attached drawing (20kB) shows almost how it would have been made today, somew
I thought the whole point of these theoretical sources is they were interchangeable. I did wonder if you could use a thermometer to measure the temperature rise, as the 1 ohm resistor would dissipate
Sorry to disillusion you academics, but it is in Nelcon and Parker, the standard A level Physics Text book when I was at school - I have it here - P.684 ! However I would add that if you increase the
You can measure viscosity by measuing the time taken for oil to drain through a tube ( at least I've always assumed that's why heating oil is graded in "seconds") I wonder if you could measure capaci
It's easier to imagine work done in hauling out a thin piece of plastic from between two charged plates rather than sucking out some liquid - does the liquid oil stick between the plates like a stron
Assuming the charge doesn't drain out with the oil, then, for the relationship Q=CV to be maintained, the voltage must rise to compensate for the loss of capacitance. My guess is the 10uF capacitor b
