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Registered Member #543
Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992
Dr. Slack wrote ...
Proud Mary wrote ...
My dismay at finding I could do nothing at all with the jumping flea SMD chips has been reversed by a compromise that took me ages to fall upon due to my unfamiliarity with the technology. I can nothing with 100 pF 50V chip capacitors, but found that 100 pF 1000V was just about big enough for me to use my standard soldering skills. The same with chip resistors: I can work with the 2W ones just fine! This still means that I shall not be able to reach the higher microwave frequencies, but is still a big advance over my previous thru-hole axials in the direction of miniaturisation.
Are you sure that the limitation is that you can *do* nothing? I used to think I didn't have the control skills to solder small stuff until I used a decent microscope. Then I realised it was simply because I could *see* nothing. Once I had sufficient gain in my optical feedback path, I found I could achieve good connections with 0402 parts routinely, and 0201 with a bit of care. Even stacking an extra pair of +4 reading glasses over your standard ones can bring about huge improvements.
I'm sure you are right and that there is an element of that in it. And yes, good magnification is essential, but I still have to deal with unsteady old hands that first held a soldering iron 50 years ago. Starting with the larger components, and then working my way down in scale when I have acquired a bit of skill seems a sensible way to go. :)
Registered Member #162
Joined: Mon Feb 13 2006, 10:25AM
Location: United Kingdom
Posts: 3141
Detecting Pulsars .... from the link posted it seems that ONE or TWO are actually detectable by amateurs, not a very exciting prospect.
My two as yet unfulfilled radio aspirations are . chatting with ISS astronauts/cosmonauts . earth-moon-earth communications. (moon bounce)
I have not worked with 0201 smd, 0804 is as small as I want to go. I prefer 0.1" matrix and through-hole components but like me they are now obsolescent :(
Registered Member #543
Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992
Sulaiman wrote ...
Detecting Pulsars .... from the link posted it seems that ONE or TWO are actually detectable by amateurs, not a very exciting prospect.
My two as yet unfulfilled radio aspirations are . chatting with ISS astronauts/cosmonauts . earth-moon-earth communications. (moon bounce)
I have not worked with 0201 smd, 0804 is as small as I want to go. I prefer 0.1" matrix and through-hole components but like me they are now obsolescent :(
I've seen people who've broken the bank making costly subterranean inductors of enormous size to detect the Schumann Resonances, but find themselves with nowhere to go once they have the Resonances resonating on the screen in front of them. So I think you are right about the pulsars pulsing away if you can detect them to which I'll add detecting the 21cm Hydrogen Line which is a goal of some rtl.sdr enthusiasts. Years of observation and something might change but otherwise it is hard to go further.
What I do find exciting is ultra-narrowband (1 Hz!) communication, where even a tinkerer of modest abilities such as myself can experiment at modest cost and perhaps surprise even myself with the distances that can be covered with just a few milliwatts. :) This - and the 8.97 kHz 'Dreamer's Band' - is the direction I hope to take my rtl.sdr experiments. :)
Registered Member #162
Joined: Mon Feb 13 2006, 10:25AM
Location: United Kingdom
Posts: 3141
In the late '70's RS used to sell a doppler radar module, I made a simple speed meter using one, passing the mixer output to an audio amplifier allows you to hear the tones, quite interresting. Certainly worth a brief 'play'.
Registered Member #543
Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992
Thank you so much for your very kind offer, Andre, but I have more stuff than I could ever hope to tinker with in a single lifetime and am very pushed for space to store what I already have.
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Microwave mixer diode substitutes
