Narrow Band 27Mhz??

Was looking thru the local Radio Shack, and came across some replacement crystals for thier XMod R/C cars, 12 crystals for under 16 bucks. Looks like Rat Shack expects thier users to swap crystals when they want to, the only warning to that of 'make sure the power is off'

Why not, thats cheap for that many Rx and Tx crystals. Paid for them, and took them home. Was expecting the 6 'normal' 27Mhz channels for use in redoing some toys so the kids could play together with them, rather than two on 'Blue'

The interesting thing, is that they aren't the normal

6 on the 27Mhz area, but are between the normal 'Red' 'Blue' 'Orange,etc

Instructions say you can race up to 12 cars at once.

these are including in the pack, both Tx and Rx for:

26.975 27.025 27.075 27.125 27.175 27.225 plus the original 6 27Mhz freqs. that come with thier car starter sets.

The new ones use a split color code, like 27.225=Green/Blue

So how did RS slip Narrowband 27Mhz past the AMA or FCC or whoever?

The Cheap Bastard in me couldn't resist, and they seem to rangecheck fine in some old Futaba 27Mhz gear with single conversion Rx's, besides the cheap Chinese made toy R/C gear I got them for, and Futaba on 'Orange' didn't seem to bother the other adjacent 'New' channels,either.

** mike **
Reply to
mike
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Illegal, apparantly Rat Shack either isn't paying attention or doesn't care.

26.975 CB channel 2 27.025 CB channel 6 27.075 CB channel 10 27.125 CB channel 14 27.175 CB channel 18 27.225 CB channel 22

So it should work fine until someone keys up their linear and asks "what's that funny noise, good buddy?"

------------------------------------------- Tim Wescott Wescott Design Services

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Reply to
Tim Wescott

Does the radio gear have FCC certification numbers? If so the FCC may have allowed this.

Reply to
Sport Pilot

Don't have one of thier Tx boxes to look for the FCC ID number, but their Online PDF manual for the car has the FCC Blurb saying Part 15 applies, and complies as a Class B device.

So saying that possibly RS has got the FCC 'OK' for this, why none of the Hobby grade Radio makers done this? seems its something the suface people would like, doubling the 27Mhz area.

Is CB Radio still a threat? I thought it was dying 10 years ago

** mike **
Reply to
mike

They still sell CB's at the truck stops. Good food at most of them.

Reply to
Sport Pilot

What is the interference threat to planes from these car xmtrs on 27 mhz? What kind of range is typical for these car radios?

Tim

Reply to
Ellestad

Don't know about your regulations, but in the UK we had "splits" many years ago.

IIRC we had a total of about 15 possible frequencies on 27MHz. Some frequencies, both main and split "spots" became risky to use after the advent of CB. Others weren't so badly affected.

Malcolm

Reply to
Malcolm Fisher

| > So how did RS slip Narrowband 27Mhz past the AMA or FCC or | > whoever?

The FCC does define channels in the 27 mHz band, but I don't think they require that you use an entire channel. I don't see why you couldn't use a fraction of one of the R/C channels, and could therefore allow people to use another fraction. Of course, if somebody had something that used the entire channel, that would interfere with all the `fractional' users of that channel.

(However, from what I've read about the zip-zaps, they don't do this. Jef Raskin seemed to think

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that the Zip Zap SE's could run 6 cars on one frequency, but from what I've read, I think he was mistaken.)

And it's the FCC that matters. Not the AMA. What does Radio Shack care if their equipment sold meets AMA guidelines? The AMA does not create law, and their frequency guidelines/policy only affects members and others that submit to their rules.

| Illegal, apparantly Rat Shack either isn't paying attention or | doesn't care.

... or you're just not as familiar with FCC regulations as they are. Which seems more likely -- that Radio Shack is selling equipment that violates FCC regulations and has been selling this specific package for years, or you just don't understand the regulations that well?

The FCC regulations do allow you to transmit on frequencies that are not assigned to you, as long as the power emitted is very low. (You'd have to read the regulations to find the exact limits -- they're not as simple as giving a miliwatts rting.) This is how BPL is allowed to trash the ham bands -- it's emitted power per sliver of bandwidth is below this limit.

In any event, Zip-zaps cars don't need much range, so it's entirely possible. If the power levels are low enough, they can legally transmit in the CB band, or any other band for that matter. And since their `stock' channels are the 6 27 mHz R/C channels, they could probably provide crystals to use the CB band that would work without any retuning.

Your car door or garage door opener, for example, probably doesn't use a frequency allocated for that. Instead, they generally use something around 390 mHz band, or in the 70 cm ham band. Normally this is fine, but I recall hearing recently that the US Navy started using the frequencies that they were allocated, and suddenly these devices `mysteriously' stopped working anywhere near the base. People complained, but the Navy was in the right.

| So it should work fine until someone keys up their linear and asks | "what's that funny noise, good buddy?"

That is true. Of course, transmitting with more than 4 watts on the CB bands is illegal, and many `linear' amps aren't very linear at all, and spew interference all over the place. If you get one nearby, they may wipe out the entire 27 mHz band (and often the 54 mHz band, the 81 mHz band ...)

Fortunately, CB, just like Usenet, is dying -- film at 11!

Also, consider what the Zip Zap cars are. They weigh like one ounce, and probably reach speeds of like 6 miles per hour. The consequences of a `hit' from a CB radio are pretty minor, and Radio Shack knows this.

Reply to
Doug McLaren

There was a time when FCC commissioners were engineers, not lawyers. Perhaps I am incorrect, but the old style commissioners at least consulted staff engineers before waving their magic wand and permitted or disallowed certain types of emissions and modulation schemes to become "licensed" or certified.

You are right in that the power level of such devices on oddball frequencies might come under a certain special classification. Many such are not well known and finding reference to them may be extremely difficult.

Ed Cregger

Reply to
Ed Cregger

Well, I have been flying lately on orange (A3...27.095) with no problems whatsoever. Have been using the HPI RF-2 4 channel AM receivers I have been buying on the internet (eBay) for anywhere from

18 to 25 dollars each. Single conversion and they really work well...very very good range. I have some old futaba modules for the gold case transmitters that work on 27 mhz, too .Tower will tell you there are no 27 mhz modules for the newer Futaba transmitters, they are wrong. I found them and they are 39.95 each and field testing (flying in my old trainer) has proven they work exceptionally well. I am doing this because after many decades of flying on the 6 meter band at my field, I find I am gettting bumped all over the place..no reason I can tell...and nothing on the moniter..still.... So I am flying back on 27 as I used to do years ago when there CB band was hot with all the CB crazies...now very quiet..especially during the day when one would fly RC, of course. Anyone wanting more information can email me direct or post to this link...or whatever.. Regards to all Frank Schwartz in Hendersonville, TN (Nashville area)
Reply to
Frank Schwartz

Here I was thinking that I could make a few bucks on my old seventies CB sets. I looked on eBay at what they were selling for and was surprised to see that they were not going for much at all. It must really be dead on CB.

Guess I'll just keep'em.

I have a few of those $20 receivers, but mine are on 72 MHz. Haven't had a chance to put them to the test yet, but soon. My foamie U-Can-Do arrived yesterday. What a weird feeling airplane, but it is what I expected. Where else can you get a model where you access the radio gear by unzipping the canopy? What a trip!

I thought my Hitec HS-80 servos would be small enough for this model, but the pockets in the wings look too small. They better get ready for a force fit, because I am not buying smaller servos. I'll probably be flying the only rendition of this model with polyhedral.

Ed Cregger, NM2K

Reply to
Ed Cregger

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CFR 47, part 95, section 207, those frequencies aren't on the list of allowable frequencies.

CFR 15 just says the device won't cause harmful interference, which is hard to control when you allow crystal swapping. Yes, you can get away with a lot if you keep the radiated emmissions down, but more because the FCC looks the other way.

BPL is different -- there are specific regulations covering it and it isn't supposed to interfere with amatuer frequencies. The FCC isn't doing it's job on that one 'cause amatuer radio operators aren't Texas millionares like the folks that run power companies.

The FCC doesn't enforce anything until someone complains, and even then only if they feel like it.

So for your RatShack example: I routinely go faster than the speed limit signs, and I often am going with the general flow of traffic when I do so. Does that mean that the sign painter didn't understand the law, or that the cops just don't enforce it strictly where I drive?

So no, I don't think that just because it's on Radio Shack shelves that it's legal -- but I also don't think that you're going to find FCC officers enforcing any rules at the local Radio Shack store.

Like driving too fast, use of an illegal radio frequency is subject to personal choice, and a possible citation. You probably won't suffer anything worse playing in the CB bands; I wouldn't advocate infringing on any military, public safety or cell-phone frequencies, however.

------------------------------------------- Tim Wescott Wescott Design Services

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Reply to
Tim Wescott

| Doug McLaren wrote: | | > In article , | > Tim Wescott wrote: | | snip | | > | Illegal, apparantly Rat Shack either isn't paying attention or | > | doesn't care. | > | > ... or you're just not as familiar with FCC regulations as they are. | > Which seems more likely -- that Radio Shack is selling equipment that | > violates FCC regulations and has been selling this specific package | > for years, or you just don't understand the regulations that well?

I do appreciate how you verified that my guess was correct -- you obviously aren't that familiar with the FCC regulatuons if you think the FCC regulations are quite this simple.

| CFR 47, part 95, section 207, those frequencies aren't on the list of | allowable frequencies. | | CFR 15 just says the device won't cause harmful interference,

Part 15 says a lot more than that. If there's any doubt --

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That's all part 15. Lots more than `the device won't cause harmful interference'.

| which is hard to control when you allow crystal swapping. Yes, you | can get away with a lot if you keep the radiated emmissions down, | but more because the FCC looks the other way.

Again, there's more to it.

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may be of some assistance here. I don't know if these are the regulations that Radio Shack Zip-Zaps goe under, but I'm pretty sure that they would not knowingly sell equipment that obviously violates FCC regulations.

Considering that the Zip-Zap cars have 40 feet of range maximum, it seems quite likely that they do fit under the regulations of this section.

| BPL is different -- there are specific regulations covering it and it | isn't supposed to interfere with amatuer frequencies.

BPL is indeed different. However, it was technically permitted even before the recent changes in the FCC regulations, though it did certainly violate the spirit of the regulations. (The new regulations did clarify things, however.)

As for `not supposed to interfere with amateur frequencies, unfortunately, the FCC has made it quite clear that protecting the amateur frequencies is not a priority. They've even given a list of frequencies that are to be `notched out', because they're important for emergency use, for example -- and the amateur frequencies are not on the list.

| So for your RatShack example: I routinely go faster than the speed | limit signs, and I often am going with the general flow of traffic when | I do so. Does that mean that the sign painter didn't understand the | law, or that the cops just don't enforce it strictly where I drive?

No, that just means that you can choose bad analogies. It's a skill that many people have.

Zip zap cars sell quite well -- Radio Shack sells lots of them. They would not knowingly sell a set of crystals for them if they felt that they violated the law, just because they didn't think the FCC would care. All it would take is one complaint, and the FCC would smack them down if they were really violating the regulations -- after all, it's not like it would be difficult at all to make an airtight case against them.

| So no, I don't think that just because it's on Radio Shack shelves | that it's legal -- but I also don't think that you're going to find | FCC officers enforcing any rules at the local Radio Shack store.

I do, if somebody complained. If you feel that Radio Shack is violating the FCC regulations, I'd say it's your civic duty to report it. I think an email to snipped-for-privacy@fcc.gov would probably be a good start, or you could call 1-888-225-5322.

You could also contact Radio Shack.

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or calling 817-415-3200 would seem a good place to start. If you were to inform them that they were violating FCC regulations, quote the relevant regulations, give the part numbers of the products that violate the regulations and state how/why they violated the regulations, they'd probably take your complaint seriously, and either get their legal department to explain how you're wrong, or correct the situation.

| Like driving too fast, use of an illegal radio frequency is subject to | personal choice, and a possible citation. You probably won't suffer | anything worse playing in the CB bands; I wouldn't advocate infringing | on any military, public safety or cell-phone frequencies, however.

Companies that sell illegal CB equipment are raided and hit with large fines on a somewhat regular basis. Not enough, mind you, but Radio Shack certainly isn't going to risk that sort of exposure just so more people can run their zip-zap cars at once.

Look at page 30 of the .pdf file I mentioned earlier -- it lists the possible penalties Radio Shack would be in danger of --

forfeiture of all non-compliant equipment $100,000/$200,000 criminal penalty for an individual/organization a criminal fine totalling twice the gross gain obtained from sales of the non-compliant equipment an administrative fine totalling $10,000/day per violation, up to a maximum of $75,000

Radio Shack is a big company. Since they've been selling radio equipment for decades, they're probably quite familiar with FCC regulations, and would not knowingly violate the rules just to sell a few more R/C cars.

Perhaps the FCC would give you a `finders fee' for reporting these obvious criminals ...

Reply to
Doug McLaren

Went back to Radio Shack, and the TX does have the FCC Id# on it, so they would have to know about it. The crystal is set for easy access, waiting to be changed.

** mike **
Reply to
mike

Ed, Buy the new servos or you will be seriously disappointed.

Reply to
Six_O'Clock_High

"Six_O'Clock_High" > a chance to put them to the test yet, but soon. My foamie U-Can-Do

You're right, Jim. I'll buy new servos. You can't blink your eyes these days without everything being instantly obsolete.

Ed Cregger

Reply to
Ed Cregger

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