Repeater to Repeater

[Wrvq441]

Greetings.

Can a repeater be used to hit another repeater.

At my cabin, there is a repeater about forty miles away that I can hit with my mobile, but barely reach with my handheld. Can I set up a Retevis RT97 on my property so I can access the better Repeater with my handheld while indoors?

[gortex2]

FCC never banned them and they are still used today. Motorola has the DVRS and other manufacturers use Pyramid or Vertex vehicle repeaters. In my truck as soon as I remove the APX from one of my charger the repeater turns on and I am able to use the HT. 

What most likely happened in your case was when narrow banding happened many did not want to pay the money to replace piece for piece. I installed many radios in ambulances and fire trucks that were basically junk because no one wanted to spend money on the proper stuff. Many complained that the issue with narrowband when in reality 75% were equipment differences. For instance we had one EMS agency that had 110 watt VHF syntors with the PacRT in the them. Owner had us install 25 watt VHF radios and they bought the bottom of the barrel VHF portables. For years they complained about coverage until they went on the TLMR system. That was only one of 100 customers I dealt with that had those issues.

[PartsMan]

What about a cross channel repeater?

For example.

Receive on 467.650 or 462.650.

Transmit on 467.550.

Seems like a lighter side of the gray area to me.

[SteveShannon]

1 hour ago, PartsMan said:

What about a cross channel repeater?

For example.

Receive on 467.650 or 462.650.

Transmit on 467.550.

Seems like a lighter side of the gray area to me.

That’s what I described in the post I’ve quoted below from the first page. However, regulations require that the frequency on your second line be in the 462 MHz channels, not 467. 467 is only for transmitting to a repeater (for purposes of communicating through the repeater) or limited testing. 
 

 

On 1/15/2023 at 10:24 AM, Sshannon said:

The more I think about this, the more I wonder why two back to back radios on different frequencies wouldn’t work. One would be on simplex to talk to the nearby handhelds and one would be configured to transmit and receive from the repeater.  Neither would be capable of simultaneously transmitting while receiving and most importantly, none of the input frequencies would be able to receive any of the frequencies that could be transmitted simultaneously. That last is key.

So, the central mobile/base station would be configured to transmit to the repeater and receive from the repeater, but because it’s not a repeater it cannot transmit while receiving and it cannot receive while it transmits.

The audio from its headphone jack is connected to the mic input on another radio which is set to a simplex channel. I’ll call it the simplex radio.  It’s set to a completely different channel than the receiver of the central mobile/base station. That audio triggers PTT or VOX on the simplex radio and is retransmitted to the OP’s handheld while he’s outside.

Because the simplex radio is incapable of receiving while transmitting, he could not interrupt the transmission, but once it ends, he can push his PTT.  The simplex radio receives his transmission and via a connection between its headphone jack goes into the mic input of the central mobile/base, triggering PTT and sending it to the repeater.

Getting the two radios to coexist without de-sensing might be a problem.  Might have to mount the antennas with some vertical separation.  Getting PTT to work on each might be a challenge.  Maybe one of those amazon simplex repeater boxes would help there.

But this seems too easy.  What simple and stupid thing am I missing?

 

[MichaelLAX]

21 minutes ago, Sshannon said:

That’s what I described in the post I’ve quoted below from the first page. However, regulations require that the frequency on your second line be in the 462 MHz channels, not 467. 467 is only for transmitting to a repeater (for purposes of communicating through the repeater) or limited testing. 

Isn't his example for a repeater input on 467.xxx?

2 hours ago, PartsMan said:

What about a cross channel repeater?

For example.

Receive on 467.650 or 462.650.

Transmit on 467.550.

Seems like a lighter side of the gray area to me.

 

[SteveShannon]

31 minutes ago, MichaelLAX said:

Isn't his example for a repeater input on 467.xxx?

 

Well, I wasn't sure.  He says receive on either 462 or 467 and transmit on 467 and I thought he was describing the frequencies of what he calls a cross-channel repeater.

[PartsMan]

Both repeaters could be receiving 467 frequencies but from different channels to avoid a loop.

.550 and .650 was my example.

[SteveShannon]

51 minutes ago, PartsMan said:

Both repeaters could be receiving 467 frequencies but from different channels to avoid a loop.

.550 and .650 was my example.

It’s simply not possible to avoid a loop with two full duplex repeaters which communicate with each other, regardless of which frequencies they are on.

Rpt 1 receives on B and simultaneously transmits on A,  Rpt 2 receives on A and simultaneously transmits on B, where it’s received by Rpt 1 and retransmitted on A. 

It can only be done if one end breaks the loop by not simultaneously transmitting on the frequency that goes back to a full duplex repeater.

EDITED: I’m mischaracterizing the problem  The true problem is not that it’s simultaneously transmitting.  The true problem is that everything each repeater receives is re-transmitted.  Introducing a delay will simply make it sound like an echo.  The solution must be to retransmit to the handheld in such a way that it’s not “repeated”.  That’s why the back to back audio signal solution I described should work.The radio that communicates to the handheld is incapable of simultaneously receiving and transmitting radio signals.

 

[WRUU653]

25 minutes ago, PartsMan said:

Both repeaters could be receiving 467 frequencies but from different channels to avoid a loop.

In Op’s scenario though he was trying to extend the signal he gets from someone else’s repeater I believe. So his method would have to hear or input from that 462 from original repeater and then put out on another 462 if I understood correctly. I liked @Sshannon back to back radio idea fwiw 

[gortex2]

This is why repeaters are linked via ethernet. Normally a UHF repeater would use a "link" frequency in another band to link them together via RF. In Ham radio its pretty simple and used a lot (more for VHF repeaters with UHF links) but with GMRS we have basically 8 channels. Using RF to link will most likely interfere with each other. To make it work well you would need a lot of filtering. And with the narrow scope of frequencies its really not possible. 

If you need to link them you need to do via another means than RF. 

When I was in NY I had a "poor mans" voter system. 2 Repeaters could be heard in most locations but portables had trouble getting back to both. Solution was same repeater frequency with different RX PL at each site and same on TX. Basically RPT 1 was on PL B Receive and PL A Transmit. Repeater 2 was on PL C Receive and PL A Transmit. Hand Held had RPT 1 and RPT 2 with those settings. When units on RPT 1 would talk folks with RPT 2 would normally here them and could answer on RPT 2. Its not perfect but works well for portable use. We did multiple public safety systems like this in the past also. Its common in the VHF repeater world in rural America.