Two-way Radio Diagrams

[Robinsonaj]

I am new to this. I am going to school to be a tech and I wanted to build a two-way radio for fun and experience. I do not feel or have the money to send on getting the diagrams. Does anybody know where I can go to get them for free.

Thanks

 

[RadioRon]

One way is to go to a business that repairs two-way radios and ask if they have any scrap service manuals that they could give you for free.

Another way is to google for "amateur radio manuals". Here is one place that has many radio manuals. Look in the "service" manual or "technical" manual for different models and you will see many schematics.

**broken link removed**

 

[sv_clintrace999]

i Guess he wouldn`t dare to build schematics like this very complicated, what he was trying to look for maybe a sort of a walkie talkie transceiver using a fixed frequency, why not try using Audiguru`s FM transmitter and add a few components for the receiver? perhaps it would be then easier using only few components

 

[RadioRon]

i Guess he wouldn`t dare to build schematics like this very complicated, what he was trying to look for maybe a sort of a walkie talkie transceiver using a fixed frequency, why not try using Audiguru`s FM transmitter and add a few components for the receiver? perhaps it would be then easier using only few components

No, he isn't going to learn very much about mobile radio by building something that simple. The most basic project i would recommend would be to build a two-way voice transceiver with these kinds of features:

- transmit and receive on channels in the range of 144 to 148 Mhz (lots of schematics out there for amateur band)
- 25 KHz channel spacing (easy to find an IF filter)
- synthesized oscillator (no point in learning about radios without synthesizers)
- FM modulation (as this is most common in VHF and UHF two-way radio)
- 2 watts output from transmitter (modest but still challenging)
- dual conversion superheterodyne receiver with 45Mhz first IF and 455 KHz second IF (relatively easy to build using ICs and readily available
filters)
- 1 watt receiver audio speaker , with squelch function

There are schematics and plans out there for similar simplified FM two-way radios, but need a bit of work to find them.

Consider a kit if you can find one. Doing it from scratch is complicated.

Lots of manuals here too:
mods.dk - Modifications for radioamateur

 

[sv_clintrace999]

Yeah yer right but he said that he`s new to this and he wanted to build something for fun and experience, so i`ll suggest he`ll go to the very simple transceiver

 

[RadioRon]

Yeah yer right but he said that he`s new to this and he wanted to build something for fun and experience, so i`ll suggest he`ll go to the very simple transceiver

You have a good point, and now I'm wondering if my advice is something too advanced. I think a kit is a good way to get into it, but they cost money too. Building anything is going to cost money, even just for the parts. I wonder if a better way would be to get a used VHF two-way (something old and inexpensive, like an ICOM IC-02AT) and use it to probe into, look at waveforms and stuff, and figure out how each little section works. That might be more productive.

 

[Robinsonaj]

You guys have a lot of good ideas. Thank you. I am currently building an FM trasmitter and I will do a little of everything. I am not afraid of a good challange and if should be fun.

Thanks Again

 

[flat5]

At a second hand store you may find an old CB transceiver that works or not very cheap. Then try to find service information for it.

 

[sv_clintrace999]

You guys have a lot of good ideas. Thank you. I am currently building an FM trasmitter and I will do a little of everything. I am not afraid of a good challange and if should be fun.

Thanks Again

Any problem with your FM transmitter you may consult Audioguru and the rest of the brilliant guys here