Looking to hire someone to design a radio device.

[yukz71]

Hi, I have minimal knowledge of electric circuits so I'm not capable of designing my plan. So, I am looking to pay someone(either via money order or Paypal). As far as price I'm open to bids from capable people. Depending on what you could design and possibly even build, I would pay up to $250.

Now, on to what I would like someone to be able to do. To me it doesn't seem overly complex, but I'm far from being able to talk.

I want to build a small device about the size of an alarm clock that has 5 lights on it and a button. Pressing the button emits a radio frequency in the range of about a mile for 60 sec then stops. A seperate unit could detect this signal and would light up 1 of its 5 lights. Each light would be for a different unit(and diff frequency). So there could be a total of 5 units all within a mile of each other that would be able to "communicate" by lighting up each other's lights.

Please post or email any questions. I am completely open to ideas and suggestions. But mainly offers and bids by someone certain they can accomplish this. Thanks for your interest. yukz71@yahoo.com

 

[spuffock]

Suggest they all run on the same frequency and send different codes.
Modular radio devices can be bought, and all that's needed is a bit of PIC work.

 

[stevez]

One limitation is likely to be the frequencies you plan to use. A mile is a long way and unlikely to be within range of license free devices.

On the surface it would seem that what you want exists within the radio control "hobby" area - range being the exception.

Good luck.

 

[yukz71]

Radio Frequencies

How big of a deal is it to 'register' or 'purchase' a frequency. I suppose you would have to deal with the FCC? In the mean time I would be pleased with just having the device be able to broadcast a shorter distance with the possibility of upgrade to a better frequency later.

 

[Nigel Goodwin]

Re: Radio Frequencies

How big of a deal is it to 'register' or 'purchase' a frequency. I suppose you would have to deal with the FCC? In the mean time I would be pleased with just having the device be able to broadcast a shorter distance with the possibility of upgrade to a better frequency later.

As you've not filled your location in, we've no idea where you might be, but as you've mentioned the FCC - presumably you are in the USA?.

As I'm in the UK I can't comment on how it's done over there, but in the UK it's a very expensive and time consuming process, with a licence costing a fair amount every year. Due to the severely limited amount of frequency space available it's also highly likely that if you are allocated a frequency, you will probably be sharing it with other users.

For short range use there are various 'licence free' radio modules available, some UK examples are listed here http://www.radiometrix.co.uk/products/product1.htm.

EDIT:
I've just been googling further, how about these , up to 20km, now they look to be more what you are looking for!.

 

[gerty]

How big of a deal is it to 'register' or 'purchase' a frequency. I suppose you would have to deal with the FCC

I'm a medic with the county rescue squad and we recently got a new frequency. We requested to stay in the same band (uhf) as the rest of the county. It took us 20 months to get all the paper work thru
If you apply to FCC for a license you cannot request a specific freq, just the band you want to stay in :?

 

[dustinpruente]

you monitor frequencies that other people are using, then you use a different frequency. i havent licensed any of my radio equipment, including WAY high power cb units.

 

[Nigel Goodwin]

you monitor frequencies that other people are using, then you use a different frequency. i havent licensed any of my radio equipment, including WAY high power cb units.

Perhaps so, but you are a criminal!, perhaps 'yukz71' is an honest man, and doesn't wish to break the law?.

You (quite wisely) don't mention your location, but in the UK you could be subject to fairly severe penalties - I know a number of people caught for unlicenced radio transmitters over the years, I've not known one get any jail time, but one did come close (it wasn't his first offence - or indeed his second!).

Obviously a mobile transmitter is far harder to catch, but a fixed transmitter is probably asking for trouble.

 

[goodpickles]

You can buy 2 way radios that transmit over a mile that do not need a license in the US. Why would you need for this?

 

[Oznog]

You're probably thinking of the FRS walkie talkies? Sure they can do a mile under some conditions. However, though unlicensed, the band is approved for person-to-person voice transmission. It is surely illegal to use for digital data or any automated transmission.

 

[yukz71]

a simplified version

Ok, this isn't going anywhere. I think my range requirements are the problem. At a shorter range could someone design a device that would do this? Basically I need a pager system, like at restaurants maybe. Could anyone design or build that? I can work on extended range later. Thanks for all the input so far.

 

[ymmy]

I want to build a small device about the size of an alarm clock that has 5 lights on it and a button. Pressing the button emits a radio frequency in the range of about a mile for 60 sec then stops. A seperate unit could detect this signal and would light up 1 of its 5 lights. Each light would be for a different unit(and diff frequency). So there could be a total of 5 units all within a mile of each other that would be able to "communicate" by lighting up each other's lights.

Sound like wireless bomb project... :roll:

 

[yukz71]

chill out ymmy

ymmy: Give me a break, wireless bomb? If I wanted to do that I could use a remote control car setup or something. Next time try not to make someone out to look like a terrorist.

 

[Oznog]

I believe there are license-free frequencies available, but they are limited in power to limit the effective range. It could be 100 ft or several 100 ft depending on the obstacles.

Obviously this is necessary when giving out unlicensed freq, or a single company would make a transmitter which would block out anyone else's products within a mile, then the next mfg would start selling something twice as powerful to overpower the first guy's device, and pointless power wars begin and nobody can count on their product being reliable.

If the short range will meet your specs, you can do it. But don't count on getting extended range later, it is probably not possible.

 

[Nigel Goodwin]

I believe there are license-free frequencies available, but they are limited in power to limit the effective range. It could be 100 ft or several 100 ft depending on the obstacles.

If the short range will meet your specs, you can do it. But don't count on getting extended range later, it is probably not possible.

The licence free modules I gave the links for above gave up to 20km range, which would probably meet his requirements - presumably they are considerably more expensive than the short range ones?.