Recent content by Hop-AC8NS

Thought I would update this thread and perhaps elicit some more responses. So far, only @Baluncore and @DaveE have participated with interesting suggestions instead of nay-sayings, so I appreciate their contributions to the discussion. The first problem a new ham experiences is obtaining...

Ah, got it—the round-trip doubles the timing spread, which could affect bit sync in comms. For APOLLO's small, flat, point-like (from the POV of the Earth looking at the Moon) reflectors, this wasn't an issue. I apologize for my confusion. I forgot that Special Relativity says it is impossible...

APD background to this discussion There is a type of photon-activated device that goes into avalanche conduction by means of impact ionization, multiplying the conduction effect of a photon creating an electron-hole pair in a semiconductor junction. This type of device is called an Avalanche...

Hmmm. Path length variation is important for a signal that has traveled 384,400 kilometers? Light pokes along at roughly a nanosecond per foot, so if there is a variation in distance of the reflection, that works out to about 100 nanoseconds per 100 feet. I don't think I will worry about that...

Yes, I expect only one patch on the Moon, a minimum of two kilometers diameter but maybe larger because of Earth's atmospheric divergence of the probe beam, to reflect temporally-tagged photons sent by my telescope toward the Moon. The receiving telescope will use light reflected from that...

The doubler requires a laser source to produce frequency-doubled green laser light. I have no intention, nor the need, to duplicate what was done for lunar laser-ranging. It will be difficult enough to add digital modulation with microsecond-wide data bits to a short, millisecond-wide, transmit...

The doubler crystal (typically KDP) requires a laser source to produce frequency-doubled green laser light. A diode pumped solid-state (DPSS) laser diode provides this at microscopic scale in a standard transistor-style package producing about a watt or so our optical power. It is not as nice...

You are right about that! What radio frequency should I be starting the modulation with? How much in frequency do we "chirp" the long RF sweep? How fast is the sweep of the modulation to occur? Over what duration does this sweep occur? I am not saying your suggestion isn't reasonable. I am...

In TARC we have a retired member, San Yoder, who spent his career involved with electrical power transmission. The next time I see him I will ask how high-tension lines in the USA are made. I am not familiar with how it's done in Australia, nor do I feel qualified to comment on the copper versus...

Thank you. I hope I won't bore anyone here. Yes, the proposed modulation scheme is a form of amplitude modulation that uses digital correlation with noise cancellation to improve a horrendous signal-to-noise ratio. RF chirp is out of the question because I don't have an affordable method of...

The power loss in transmission lines is unavoidable, but when alternating current is involved there is also the problem of "skin effect" causing most of the current to flow in a narrow layer near the surface of the wire. This is avoided with direct current transmission. See, for example, the...

FCC-licensed amateur radio operators are NOT professionals, by definition. We pursue the hobby without pecuniary interest. Professionals are welcome to participate, but it is never a requirement. Hams, who can afford it, do often purchase rather than build their "rigs". Hams call their station...

It wasn't intended to be. I believe the fuel cost per kilowatt-hour to generate electrical power is much less than the continuing, and increasing, cost to build and maintain the infrastructure that supports electrical power transmission over long distances for an increasing demand, year after...

You are missing WHY the power plant is more effective using high voltage. It is not for YOUR benefit, but is for the benefit of the utility providing your house with electrical energy. The reasoning is simple: for a given voltage at the power plant, the amount of power it can deliver is the...

In the mid 1980s I was working on classified digital image processing for a three-letter agency. We also laid out ground truth targets. I was allowed to participate in a couple of those deployments since I was originally hired to upgrade the portable radiometer used to collect GT data on...