User:Gah4/sandbox5

Dubious
There is a Dubious claim on the use of dBmV in cable television systems, and the use of 75 ohm cable. The use of 75 ohm cable for CATV systems is so widespread that I don't see anything dubious. In days past, it was not so unusual for TV antenna inputs to be balanced 300 ohm twin lead, that is rare. The impedance of a folded half-wave dipole antenna is close to 300 ohms, but CATV only uses coaxial cable. Gah4 (talk) 17:41, 10 October 2016 (UTC)

There is also Dubious related to nuclear hardness. I presume this is related to hardening of missile silos, and not a property of nuclear physics. I can't say much about the dubiousness in this case. Gah4 (talk) 17:41, 10 October 2016 (UTC)

OK, I removed: dB is always a relative power measurement, but voltmeters measure voltage. As TV cable is reliably 75 ohms, this isn't a problem. In other cases, it is much less obvious. It seems that audio uses a 600 ohm reference, as far as I know, even when it isn't actually 600 ohms. At audio frequencies, reflections aren't a big problem like they are at RF. If this is still a question, then somewhere else the article should make obvious the meaning of voltage vs. power measurements. Gah4 (talk) 06:29, 13 October 2016 (UTC)

TLC
Either I don't understand how it works, or it doesn't work right. I tried #expr, that is,  and it didn't come out right. Gah4 (talk) 00:58, 2 November 2016 (UTC)
 * Where are you using this? Examples always help. But for ref, isn't a template, it's a parser function. -- Red rose64 (talk) 08:41, 2 November 2016 (UTC)
 * It was in a talk page, suggesting the use of  .   Since it looked like a template, even if it wasn't (which I didn't know), I thought it should parse the same way.  I knew about tl and tlx but not tlc. Gah4 (talk) 10:59, 2 November 2016 (UTC)

April Fools Day
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