From G3PLX: Jim said: This is fine, and the same as Dick's Topload3 diagram, but with the parallel wire stub replaced by coax - but in Figure 2b of the original article, the connections are different
From G3PLX: Dick's diagrams do look puzzling if you look at them literally, so I can sympathise with Jim, but try it this way... The capacitance hat is on the top. In stage 1 of the thought experimen
From G3PLX: Effectively what Dick is suggesting is having the coil physically at the bottom where it can be housed and adjusted, but electrically at the top. This is done by extending two wires down
From G3PLX: I have not listened for the Californian Naval rtty station on 135.95 for a while. I note tonight that they seem to be using a new mode which appears as five carriers at 25Hz spacing centr
From G3PLX: Dick: Sorry, decimal place wrong. The emitter resistor should be about 2200 ohms, or to be precise (9-0.7) volts divided by 3.5mA. I hope you haven't damaged the meter already! 73 Peter
Dick: With the figures you just gave, I would suggest you to connect the voltage from the RF sensor circuit straight to the base of an ordinary npn transistor, connect the negative terminal of your 1
From G3PLX: Mike: Be careful about using colour-fading as a guide to the performance of rope in sunlight - the differences tell you more about the pigment used than the UV resistance of the rope itse
From G3PLX: Mike: If I am right, it means the transmitter is sending ..010101010101.. at 50 baud. It spends 20mS on F1 then 20mS on F2, where (F2-F1)=50Hz. This is eqivalent to a carrier half-way bet
From G3PLX: After seeing the posting about the SAQ transmissions on 17.2kHz here, I thought I would try patching my audio spectrum analyser program to sample at 48kHz instead of it's usual 8kHz. This
From G3PLX: Marek: That's interesting about the tape. I cannot picture exactly what you have there, but it's well-known that some materials will degrade (e.g. lose colour) quickly when exposed to UV,
From G3PLX: Marek: My suggestion about UV was based on your description of the symptoms, and it sounds as if you agree with this, but I think it would be most useful if, before you modify the install
From Peter G3PLX: Marek: The 'rash' or 'burning' effect makes me think of sunburn or exposure to ultra-violet light. Could it be that there is some ionisation, perhaps due to high voltages, which giv
From G3PLX: Mal: The big resistor should not dissipate anything at all if the two amplifiers are both operating and giving the same output power. Only if one amplifier output drops below the output o
From G3PLX: Dave/Brian/Jim/all.. Thanks for the feedback. I also received one from Bob VE7BS describing his pal's results from the top of a tower block with a whip on top-band. Brian's point about sh
From G3PLX: The nearest thing still around that must sound like spark, is LORAN. After all, it is generated in exactly the same way. The only difference is that the LORAN megatron is driven with 6 pu
From G3PLX; Alan G3NYK gave some idea of how stable Droitwich 198kHz might be. I had the chance to leave my GPS-locked system monitoring it over most of a day. The results may be of interest. During