http://driving.ca/chevrolet/auto-ne...dge-observatory-has-to-use-30-year-old-trucks Does anybody have more specific knowledge of these? I'm curious how far they took it. Do they use an air starter? Is there an air starter for an old 6.2? Do they have an alternator? The cords make me think they just run battery only. Looks like they also have an old Dodge. I think it would be a neat challenge to see how non-electric you could make something like a 1986 Ford truck or something more modern.
Some mines also have rules about RF interfering with blasting frequencies, too. I think what causes the most RF interference is coils and spark plugs, hence the diesels. THe modern stuff all has too many gismos, to be safe, under these type circumstances... A diesel can be left idling, and a starter not running, causes no interference...
I doubt they unhooked the batteries and went to air start, or removed wiper motors, turn signals and ignition switch. They've got 110 volt going to the block heaters, so it's not like they don't have any electricity at the site. They probably just putter around in those things with manual injection motors to limit their output when running. I don't think they would be 6.2's either, those are like 70-72 suburbans, would be too early for a 6.2 wouldn't they? I bet the gov't paid someone to put the diesels in, something like a small perkins or such. Just because I noticed, the wikipedia article on suburban's, shows a picture of 1970 suburbans, its in the same parking lot of the observatory, that the article is about. https://en.wikipedia.org/wiki/Chevrolet_Suburban
Yes you are right, much too old for a 4 cycle V8 diesel, never thought of that. Those are late 70s early 80s at the earliest. I wonder if they are 4-53s or something Detroit?
The Checkers used a Perkins....maybe the 'burbs were converted? Ed
Looks like the burb has a 350 badge.
Slightly O/T but I used to know a fencing/yard building contractor who disliked "modern trucks" with electric starters and batteries. He reckoned they were unreliable in the bush and much preferred his magneto ignition Inters . . . I was just a big lump of a lout probably back in '57 or '58. Cheers.
Some of the mines in Illinois of the late 60's used Ford pickups with 3-71 Detroit Diesels.
I wouldn't rely on any of the technical aspects of the article to be too precise. Yeah. Cause they do the same thing, right?
I read it on the internet. It must be true, right?
The diesels at the observatory thing was something I have known about for years. It just popped into my head to ask you guys so I did the search and came up with that and posted it so people would have some idea what I was talking about. But that article is not where I first learned of this subject.
I chuckled at that part too. It's funny, we're all curious what's actually in them for engines and how they're set up, most people reading the article are just bemoaning the fact that some poor gov't department has old vehicles.
I chuckled, at that one roo, article had to be written by an english major, or worse, yet a journalist...
I was gonna comment that my 1995 Dodge with mechanical 5.9 is about as electrical free as it gets. But looks like they already got a second gen in that old suburban line up. The starters probably don't cause a problem, as they are only running very briefly. The alternators would probably be what effects the telescope, with the rotating magnetic field and all. If I understand the telescope right, electrical systems are ok, ie normal AC power systems. But sensors, computers and data transfer systems all talking to each other makes interference.
I suspect they want to minimize continuous interference from vehicles around the antenna. A starter will be brief interference and they probably recognize the noise signature of a starter if the antenna picks it up. All the electronic gagetry and b.s. running in a newer vehicle will have a wide continuous noise spectrum that probably drowns out what they are trying to observe. Even on a diesel, since obd came to be, you have data buses that are not exactly wired to be noise free (looking at Ford here...) later models may have more than one bus type (ford using both Canbus and SCP bus. Then you got things like PCM controlled alternators, PWM fuel pumps, PWM electric fans, instrument clusters, hvac, radio, tpms, all creating a noise spectrum of some sort. Your old diesel has the starter, mechanical fuel pump, and alternator-which you don't need to run the vehicle, only recharge the battery after a start.
I'd like to thank you for sending me down another internet rabbit hole. That truck article incidently has been floating around the internet since 2000. Rehashed every couple of years. Randomn tidbits from various sources; https://www.wired.com/2009/10/gbt-nrao-tour/ https://usatoday30.usatoday.com/tech/science/2009-01-02-interference-hunters_N.htm
What kind of work do you do? I'm interested to read more about various vehicle comm systems. In my other life, I do commercial radio work in the VHF world, where we are always getting hammered on our mountaintop sites by more and more noise floor from electronic garbage. Converting that watt figure gives -290 dBm which is the scale I think of. We think a receiver is sensitive if it does -124 dBm. Even the natural noise floor is not much lower than that, they must be listening to different kinds of signals.