Sirius antenna locations?

Gee, Don, did you try the satellite radio group and find that it's 90+% people arguing over whether XM or Sirius is better at the maturity level of a 6 year old? :-)

I've wondered the same thing about the antenna location and, trying it at lots of different positions without any significant effect, my guess always has been that some tech write asked some engineer, "Where should the antenna be placed?," received the answer "on the rear of the vehicle is good," and decide it was a lot more important than it really is. Hopefully we'll hear from someone who knows for certain...

Use a head unit that has line-level inputs? You definitely lose some fidelity going through the antenna insertion route...

---Joel

Not so much noise from the engine but all those little controllers under the hood.Many aAutomotive EEs don't seem to be the experts when it comes to EMI. Then there are all those cell phone yappers and, unfortunately, those are mostly sitting in the driver seat which happens to be up front.

I have seen some gross stuff in automotive. For example bang-bang PWM of windshield wiper motors. Chokes? Capacitors? Zilch.

Either the designer was incompetent or he hated Rush Limbaugh ;-)

I develop the OEM stuff for the automotive. The EMC and EMI requirements are really hard. FCC Class B is a joke compared to that.

The aftermarket products are the completely different story. SMPS trashing AM band is pretty much de-facto situation.

Vladimir Vassilevsky DSP and Mixed Signal Consultant

That may be so but I've seen lots of horrible performance. We used to be able to make cars sputter or stall using ham radio transmitters. When I bought my car I asked the dealer for the version with the least amount of electronics in there.

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My "guess" would be that locating the antenna as recommended would minimize the length of exposed coax, and thus, serve to minimize damage from car wash machines and the like.

I don't see any electrical or EMI issues involved here. None of any consequence, that is.

-mpm

I have a "GW Instek" (made in Taiwan) power supply that goes nuts (loses regulation, output often hits the rails!) when you key up a 1W handheld radio (on 2m) within a couple feet of it. :-(

Hopefully GW doesn't OEM automotive parts...

As I've suggested before, I think a big downfall in today's EE curriculum is that The Digital Kids are often never given a chance to play with a spectrum analyzer and see all the havoc that they can readily create...

They do provide a little plastic "cover" that snaps over the top of the (very small -- even smaller than RG-174) coax that has a think strip of "sticky tape" on the bottom to try to protect it.

I think it's designed in Taiwan but made in mainland China. Got a scope from them and that holds up quite well. Actually better than a major oh so famous US brand which is why I bought it.

A really bad example was a TDS220 that was spewing out so much conducted noise from its backlight inverter or whatever that it had us fooled for almost an hour. We started chasing 40/80kHz noise until we found out that it didn't come from my circuit. Changed scopes, noise gone. Turned TSD220 back on, noise clearly visible in other scope. Pathetic.

And that brings us older folks tons of work. Problem is, some day we'll be too old for that.

My XM antenna is mounted at the front of the vehicle. It is a through- glass design. On the same vehicle, the Sirius antenna is mounted on the roof, but still near the front of the vehicle.