Discussion in 'Instruments / Avionics / Electrical System' started by Streffpilot, Jan 10, 2018.

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1. Jan 10, 2018

### Streffpilot

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Hey, I was sitting at work and had a hair brained idea.....how possible would it be to create your own radio....I see websites of ham radio guys using arduino's with a touch screen to control it......what say ye brilliant minds?

2. Jan 10, 2018

### Wanttaja

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Probably would be possible. However, the FCC has rules for aircraft-band radios to prevent them from bleeding over into other frequencies, etc. Would make the job tougher, and you'd probably need a lot of RF smarts and expensive test gear.

Interesting hobby project, but probably not too cost-effective. One can buy a handheld for $200, and even mount it in the panel like I did.... Ron Wanttaja Pops and Chris In Marshfield like this. 3. Jan 10, 2018 ### N659HB ### N659HB #### Active Member Joined: Jul 15, 2017 Messages: 28 Likes Received: 8 Location: SC Midlands Ron, to what is your Fun meter attached?:roll: MadRocketScientist and mcrae0104 like this. 4. Jan 10, 2018 ### cluttonfred ### cluttonfred #### Well-Known Member Joined: Feb 13, 2010 Messages: 6,384 Likes Received: 2,240 Location: World traveler Hey, this is a family-friendly site, don't answer that, Ron! Streffpilot, for an alternative project you might consider one of the many Arduino-based avionics (EFIS, gauges, etc.) that have been discussed here on HBA and elsewhere. 5. Jan 10, 2018 ### Arthur Brown ### Arthur Brown #### Well-Known Member Joined: May 1, 2016 Messages: 138 Likes Received: 15 Location: London Getting a DIY transceiver past all the approval tests will cost more than buying a good one, the making one is easy! 6. Jan 11, 2018 ### TFF ### TFF #### Well-Known Member Joined: Apr 28, 2010 Messages: 11,647 Likes Received: 3,274 Location: Memphis, TN The only transmitters you can build are ham. All else has to be FCC approved. Wayne likes this. 7. Jan 11, 2018 ### pictsidhe ### pictsidhe #### Well-Known Member Joined: Jul 15, 2014 Messages: 6,872 Likes Received: 1,851 Location: North Carolina You'd need to be a ham to build your own. That has strings and knowledge requirements. 8. Jan 11, 2018 ### Pops ### Pops #### Well-Known Member Joined: Jan 1, 2013 Messages: 7,144 Likes Received: 6,034 Location: USA. At one time many years ago, Jim Weir, (RST) and articles in Kitplanes, sold a kit of a Nav-Com that you built and sent back to the company for aliment . I built about 6 or 7 of his audio panel kits and also his 3 light marker beacon bench tester. Jim is a sharp dude. BJC likes this. 9. Jan 11, 2018 ### cluttonfred ### cluttonfred #### Well-Known Member Joined: Feb 13, 2010 Messages: 6,384 Likes Received: 2,240 Location: World traveler I was going to recommend Jim Weir's site in this thread but when I visited it I found that right now he only offers air and ground antennas, an ADSB/GPS/transponder, and t-shirts. There are, of course, many great DIY articles available on his, he just doesn't seem to be selling the components. http://www.rst-engr.com/ 10. Jan 11, 2018 ### Himat ### Himat #### Well-Known Member Joined: May 5, 2011 Messages: 2,799 Likes Received: 646 Location: Norway Then, if you source the radio, tx/rx, module and only build and program the interface? 11. Jan 12, 2018 ### Bill-Higdon ### Bill-Higdon #### Well-Known Member Joined: Feb 7, 2011 Messages: 446 Likes Received: 139 Location: Salem, Oregon, USA let's see you find the modules. 12. Jan 12, 2018 ### Highplains ### Highplains #### Well-Known Member Joined: Jun 3, 2014 Messages: 355 Likes Received: 135 Location: Over the Rainbow in Kansas, USA Given the specifications, and maybe$10K for test equipment rental, a functional radio could easily be built using commonly available purchased hardware. I spent most of a decade designing one of a kind communications hardware for DoD alphabet companies back in the dark ages. Of course back then cost was not the object.

13. Jan 12, 2018

### pictsidhe

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You need some qualifications to legally certify a radio. Being a suitable ham is one option. The others get pricey.

14. Jan 12, 2018

### Derswede

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Aircraft frequencies are off limits for ham transmit operation. Even modifying a VHF ham radio to transmit would be a major fine $. I see FCC actions against illegal CBers (high power, in the ham bands, etc) all the time, the fines are in the tens of thousands. Also, most Amateur rigs in that range are FM modulation, not AM as aircraft radios are. Now, a RECEIVER is fine. I have built several kits that cover the air band and which allow me to listen to the ops at the local airport. A couple of kits are available with some searching. However, I have found several handheld radios for under$100 off of craigslist and at local hamfests. To build one to FCC specs would take the assets of a Yaesu, an Icom, etc. Is it possible to build one? Yes. Would I want to build a transmitter for such purposes? No.

Derswede (N4ABA)

Last edited: Jan 13, 2018
15. Jan 12, 2018

### Pops

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Used to take a First Class FCC Radiotelephone License to tune or adjust any transmitter over 50 milliwatts. I had an appointment to take the test in the mid 1965 but got very sick for several weeks and never got a new appointment to the test.

16. Jan 12, 2018

### spaschke

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It would be quite easy to build with a lime SDR and a small PC or mac mini. This software approach would need a faster computer than a raspberry pi. The lime SDR is new on the market, is one of the few SDR products that will transmit full duplex and costs around $300 if I remember correctly. A small pc and monitor might cost$500-800. GNU-Radio would be an easy to use programming environment. AM or FM, as well as filters and tuning is implemented in software, thus the need for a fast computer. An output booster may be needed also. I think the output signal strength is up to 10 dBm.
Could you use it? I don't know.

17. Jan 12, 2018

### mcrae0104

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Too bad the folks at Heathkit don't offer an aviation radio. (They're the modern-day version of the company that produced the Heath Parasol.)

18. Jan 12, 2018

### TFF

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I wish Heath was still around. Been gone as long as the Trash-80 has been.

19. Jan 12, 2018

### mcrae0104

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20. Jan 13, 2018

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