Arduino Forum

Using Arduino => Audio => Topic started by: MountainmanADK on Apr 20, 2019, 11:41 pm

Title: 2 meter fm reciever
Post by: MountainmanADK on Apr 20, 2019, 11:41 pm
i am planing on building a aprs igate from chapter 7 of "ham radio for arduino and picaxe" book. It uses argent data radio shield which takes audio from a 2 meter receiver. Code at http://hamradioprojects.com/authors/dl8rds/+airgate/code/  or http://qth.me/dl8rds/+airgate/code
shield info at http://wiki.argentdata.com/index.php?title=Radio_Shield

My goal is to integrate a fm receiver to the stack. I have found many projects on the web using tda7000 ic for receiving broadcast fm radio. i don't know enough to know if modifying this circuit would work. Can i just adjust the LC to match for the 144.39Mhz. any help constructing a small fm receiver for that frequency would be appreciated. I also assume i will need some kind of AF amp before inputting into the argent radio shield.
Title: Re: 2 meter fm reciever
Post by: AWOL on Apr 21, 2019, 11:06 am
Probably easier/cheaper to use a Baofeng 2 metre handheld.
Title: Re: 2 meter fm reciever
Post by: MarkT on Apr 21, 2019, 02:51 pm
TDA7000 input frequency rating is upto 110MHz only.  I also doubt the VFO would be stable enough for
narrowband FM and you have no solution for SSB with that chip AFAICT.
Title: Re: 2 meter fm reciever
Post by: Geek Emeritus on Apr 21, 2019, 03:06 pm
search term: RTL-SDR radio. the cheapest one on eBay does what you want:

the cheapest RTL-SDR on eBay (http://search term: RTL-SDR receiver. $16.99 up on eBay. 25 MHz to 1760 MHz. Support:AM, NFM, FM, DSB, USB, LSB and CW reception modes.  https://www.ebay.com/itm/RTL-SDR-Receiver-0-5PPM-TCXO-HF-SMA-Support-AM-NFM-FM-DSB-USB-L-RTL2382U/123690776085?hash=item1ccc8b7615:g:ZrUAAOSwHlRbRHnV)

Title: Re: 2 meter fm reciever
Post by: MountainmanADK on Apr 21, 2019, 04:30 pm
Thanks I know cheap radios are out there but it's not about the money. Looking to learn and I only need fm receive capability for this project. Found documentation on mc3363 that looks like it could be possible???
Title: Re: 2 meter fm reciever
Post by: MarkT on Apr 21, 2019, 07:14 pm
Looks pretty capable, but all the support components like tuned circuits and filters and crystals make for
a complex build that requires RF alignment with suitable testgear - its not an out-of-the-box solution
unless someone already does a 2m module using it.
Title: Re: 2 meter fm reciever
Post by: Grumpy_Mike on Apr 21, 2019, 09:12 pm
This page has a project that will show you what is involved:-
http://pages.suddenlink.net/wa5bdu/2M_RX.html (http://pages.suddenlink.net/wa5bdu/2M_RX.html)
Title: Re: 2 meter fm reciever
Post by: MountainmanADK on Apr 21, 2019, 09:34 pm
Thank you grumpy_mike this is what I was looking for