Radius programming for repeater use

[darrelhillman]

Hi friends. This is my first thread here in Radio Reference. I thank you all for the opportunity. I am combining 2 Radius M120 as a repeater with an interface cable, for GMRS frequencies. The question is if I want the repeater to Rx in 467.650 and Tx in 462.650 with PL codes, how do I program the Tx frequency of the Rx radio and the Rx frequency of the Tx mobile radio??? Does the Rx mobile is simplex and the Tx radio the 5MHz shift? Please reply if you can understand what I am asking. Thanks in advance.

Darrel

 

[ramal121]

The easiest thing to do is program both radios the same ie. RX 467 and TX 462. That way if something bad happens, like burn up the TX PA, just swapping the cables around gets you back on the air in no time.

 

[kb0nly]

If your talking the mobile radios that are used with the repeater you would program them the opposite, rx on the mobile is the transmit on the repeater and vice versa. Not that hard.

If you mean how can you program them... Then you need the software and a RIB.

 

[darrelhillman]

Thank you both.

I had programmed the units before. My doubt was that The RX freq. on one unit, and the Tx freq. on the other are not needed, becuse the radio transfer the information directly to the Tx of the 2nd unit. So programming both in Simplex should do the job???

I also have a question about the Duplexer. I have a 6 cavity (made in china) duplexer, but read that the big large cavity duplexer (not sure if it is a band/pass type) was better for reception and Tx. These are more expensive and take more space, but will it work better???

The purpose of this homebrew repeater is to be used in a boat to communicate to the tender dinghy when getting into the shore. VHF Marine freq. cannot be used by children for communication.

Thank you again in advance.

Darrel

 

[kayn1n32008]

Wirelessly posted (Mozilla/5.0 (BlackBerry; U; BlackBerry 9780; en-US) AppleWebKit/534.8+ (KHTML, like Gecko) Version/6.0.0.600 Mobile Safari/534.8+)

Mobile duplexers are Band pass only. The chinese ones are decent, a friend of mine compared a chinese mobile duplexer to a Cinclair mobile duplexer. The chinese ones are a copy of the cinclair ones and actually out performed the cinclair ones.

If your repeater is not going to be in a high noise location the the mobile duplexer sould be fine.

We recently swapped a set of mobile duplexers for a 4cavity band pass/reject duplexer. Around 85db of reject. We are putting 12.5w in and getting 12.1w out to the feedline. The mobile ones were only passing 10w to the feedline: Moral of the story: IF tuned properly pass/reject cavities will have little loss.

 

[RKG]

I had programmed the units before. My doubt was that The RX freq. on one unit, and the Tx freq. on the other are not needed, becuse the radio transfer the information directly to the Tx of the 2nd unit. So programming both in Simplex should do the job???

I also have a question about the Duplexer. I have a 6 cavity (made in china) duplexer, but read that the big large cavity duplexer (not sure if it is a band/pass type) was better for reception and Tx. These are more expensive and take more space, but will it work better???

The purpose of this homebrew repeater is to be used in a boat to communicate to the tender dinghy when getting into the shore. VHF Marine freq. cannot be used by children for communication.

Thank you again in advance.

Darrel

A repeater is quite unnecessary for the proposed use (i.e., comms between the base station and one subscriber). Repeaters provide function only for comms between or among two or more subscribers who are distant from one another.

 

[darrelhillman]

True, RGK. Except if you want to move around the boat with handheld, and have the repeater well stored and protected against the harsh salt water enviorment, and 2) when 1 group is at shore and the other is far Scuba diving in the dinghy. With the base type, the group around the boat is limited to be attached to the base station. Also HT can be well protected with water resistant covers.

Thanks for the comment. There might be other ways to go around the comms problem I have had in the past.

Darrel