What is you experience? Any options I might need/overlook?
Any mobile Crossband repeater recommendations?
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I previously used a Kenwood D710 for that and it worked fine. If the Kenwood V71A offers crossband as well, it is a lower cost option.
The TM-V71A does crossband as well. Though I understand recent versions no longer allow for DTMF remote control like older models did.
To be fair, many dual-band, dual-receive radios will have this feature even if their manufacturers don't actively promote it.
To be fair, many dual-band, dual-receive radios will have this feature even if their manufacturers don't actively promote it.
Just remember that heat is always a major concern, since your radio is transmitting both ways. Most amateur radios are not designed or certified for 100% duty cycle.
What about dual power levels ? I would need high power on VHF and low on UHF.
I've had good success with the Yaesu FT-8900, the TYT 9800 and Anytone AT-5888UV. If its just to extend the range for one person you can run high power to the distant station and low power to your handheld or personal radio and they seem to work fine without overheating. You don't want to run them high power on both bands especially with multiple users going through it.
FKimble
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Using a FT8900 for crossband. If you can hear the repeater with your HT, but just can reach it, then program your crossband to just transmit to repeater but not transmit back to the HT. I do it by putting a different tone on the receive from the repeater. Tone doesn't match so crossband radio does not transmit on the UHF side. Cuts transmit time roughly in half.
Frank
Frank
Yeah, Kenwood calls that "locked band repeating" in the TM-V71A and it's switchable with crossband repeating.
I have both FT-8900 and FTM-400DR and one thing I'm not crazy about with how Yaesu inserts about a half second transmit hang during crossbanding. There doesn't seem to be a way to turn that off (I could on my TM-V71A).
I have both FT-8900 and FTM-400DR and one thing I'm not crazy about with how Yaesu inserts about a half second transmit hang during crossbanding. There doesn't seem to be a way to turn that off (I could on my TM-V71A).
Cross band repeat was a big deal in the 90’s, seems to have fallen out of favor by manufacturers and hams. Maybe due to better understanding of the rules requiring ID and station control.
Most Icom mobiles will cross band repeat, but don’t have a CW identifier.
Kenwood mobiles ID in both directions which will drive linked repeaters crazy cluttering up the system with more CW ID’s. Most trustees in my area don’t want cross band operation on their linked repeaters.
The lack of a DTMF control on the post 2001 (?) Kenwood mobiles is a head scratcher. It was a great set up.
The Yaesu I’m not familiar with as I never set up my 300DR for cross band.
Most Icom mobiles will cross band repeat, but don’t have a CW identifier.
Kenwood mobiles ID in both directions which will drive linked repeaters crazy cluttering up the system with more CW ID’s. Most trustees in my area don’t want cross band operation on their linked repeaters.
The lack of a DTMF control on the post 2001 (?) Kenwood mobiles is a head scratcher. It was a great set up.
The Yaesu I’m not familiar with as I never set up my 300DR for cross band.
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MTS2000des
5B2_BEE00 Czar
The "locked band" mode should be used whenever possible, provided one has a dual band HT with independent TX/RX. FWIW even my APX8000 and APX8500s will accept a VHF RX and UHF TX or vice versa for setting up a "locked band" channel/mode. This ensures the following:
1-ID requirement goes away (unless you actually key up)
2-Duty cycle on your crossband mobile is minimized
3)-Less chance of interference
Remember that one should always ask permission before just setting up a cross band or radio gateway on someone else' repeater/system. Contrary to popular belief, repeaters are property of others. Furthermore, system owners should know who is cross banding/patching on their repeater(s) in case of interference. It's also good practice to run full CTCSS/DCS to ensure RF noise or unintentional carriers don't cause interference.
ID requirements under part 97 do require that a transmitter identify in "CW" or "the mode of transmission" at the end of a series of transmission, or 10 minutes of exchanges occur. This applies if one is crossband repeating a local repeater on a simplex frequency and never actually keying up on their portable.
1-ID requirement goes away (unless you actually key up)
2-Duty cycle on your crossband mobile is minimized
3)-Less chance of interference
Remember that one should always ask permission before just setting up a cross band or radio gateway on someone else' repeater/system. Contrary to popular belief, repeaters are property of others. Furthermore, system owners should know who is cross banding/patching on their repeater(s) in case of interference. It's also good practice to run full CTCSS/DCS to ensure RF noise or unintentional carriers don't cause interference.
ID requirements under part 97 do require that a transmitter identify in "CW" or "the mode of transmission" at the end of a series of transmission, or 10 minutes of exchanges occur. This applies if one is crossband repeating a local repeater on a simplex frequency and never actually keying up on their portable.
The TM-V71 gets my vote. I have used mine when providing support to a long bicycle event, with 2m on high power and 70cm on the lowest power. (I could not reliably receive the repeater on my handheld.)
I'm currently using a TM-V71A in my cabin on top of the hill, so I can crossband repeat to the local repeater 65 miles away, from my house in town that is about 700 feet lower than the hills. That has worked very well the last few months, no problems yet. Setting the power differently on each band is no problem and works well.
When I had them set both at High power it could get decently warm when people started jaw jacking down in the city. With the height advantage I have LOS to the repeater 65 miles away, plus the sledgehammer X700HNA I can mange just fine on 25 watts on both. Considering my cabin was cold during testing, I would think that running one on high power both ways would be inadvisable in most circumstances. Especially in a car, especially if you run it during hotter weather, ect. Amp drain on a vehicle battery is another consideration.....
I have one in the car for emergency crossband, but I haven't gotten around to doing a thorough testing yet. Once the 3 feet of snow melts I'm planning on at least something.
When I had them set both at High power it could get decently warm when people started jaw jacking down in the city. With the height advantage I have LOS to the repeater 65 miles away, plus the sledgehammer X700HNA I can mange just fine on 25 watts on both. Considering my cabin was cold during testing, I would think that running one on high power both ways would be inadvisable in most circumstances. Especially in a car, especially if you run it during hotter weather, ect. Amp drain on a vehicle battery is another consideration.....
I have one in the car for emergency crossband, but I haven't gotten around to doing a thorough testing yet. Once the 3 feet of snow melts I'm planning on at least something.
pcunite
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Did you ever get a chance to test the TM-V71A in cross band repeat mode? What's it take to melt it?
Keep the power at medium, it will run all day in the car. I think all the concerns about cross band repeat torching radios is probably more about high duty cycle plus full power.
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