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Vintage Amateur and Military Radio Amateur/military receivers and transmitters, morse, and any other related vintage comms equipment. |
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2nd Feb 2021, 5:47 pm | #41 |
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Re: 'Special installation for (Bristol) Blenheim aircraft' - lash-up of test oscillat
Maybe a little test detector, built tiny for low stray L, into a DC meter. Use a Schottky diode.
Proving flatness once you get up in frequency becomes, um, interesting. I cheat. I have microwave power meters to 40GHz and a spectrum analyser to 22GHz, but that may be getting a lot more serious than you'd want to do for fun. (That analyser goes to 110 GHz with external mixers) proving these instruments and having a traceability path to national standards labs is also, um, interesting. Just rigging something up at home that will give a reasonable indication to a few hundred MHz takes you a fair way down the path. David
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2nd Feb 2021, 6:11 pm | #42 | |||
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Re: 'Special installation for (Bristol) Blenheim aircraft' - lash-up of test oscillat
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In my last major project, that was the area where I had the most frustration and the most learning, pushing the boundaries of my test equipment, knowing when a reading was spurious and then deciding what else I could do about it.
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Al Last edited by Al (astral highway); 2nd Feb 2021 at 6:38 pm. |
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2nd Feb 2021, 9:13 pm | #43 |
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Re: 'Special installation for (Bristol) Blenheim aircraft' - lash-up of test oscillat
The classic uni lab setup for teaching waveguide and lecher stuff used an AM'd oscillator as the RF source, and you used a diode detector into an audio millivoltmeter to compare levels in different places.
David
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