Question About my Setup and Crossband Repeating

[H0LLYW00D]

I have installed in my truck a Yaesu 8900 and tuned the left side to 118.200(my local ATC frequency). I then tuned the right side to 145.000 and then turned on the cross band repeat as per the manual.I then turned on my Yaesu 270 and tuned it to 145.000. When someone started talking on 118.200 the radio would just repeatidly make a mic clicking noise but I could not hear the transmission on the handheld. If i tried to transmit from the handheld it of course gave an error on the 8900 as I am not able to transmit on 118.200. I am curious to know if you must be able to transmit and recieve on both frequencies for the crossband fuction to work or if I just have something confirgured wrong. I want to take pictures at the local airport but want to listen to ATC while I am out of my truck.

Any help and/or guidance is much appreciated.

 

[xtatik]

I'm not sure how the regulations read in Canada, but here in the States these retransmissions would be illegal. I wouldn't know, but it's possible they read similarly in Canada and the radios' cross-band function is blocked from retransmission of signals from outside amateur band allocations. I don't know how Industry Canada regulates retransmisions, so this is just a guess. Down here the FCC is clear on this issue.

"97.113(c) No station shall retransmit programs or signals emanating from any type of radio station other than an amateur station..........."

The other reason might be that the radio is struggling with the different modulation modes. Airband at that frequency is usually Amplitude Modulated (AM) and you are wanting the radio to retransmit the same signal using Frequency Modulation (FM). I think the 8900 can listen to AM but it won't transmit AM.

 

[H0LLYW00D]

That sound like it might be the problem what I will try is doing a repeat on another set of a mature frequencies with a friend and see if that works and go from there.

 

[Tennmogger]

Does this transceiver use the 2m antenna port for the aircraft band? Does the aircraft band share part of the 2m Rx system, that is, aircraft reception actually passes through the 2m side of the radio? ... all potential problems. The crossband repeat would normally mean 2m to 70cm, or vice versa, and those are separate systems with their own front end filters, etc.

Ignoring the above, the problem might also be the lack of selectivity on the AM/aircraft band (where performance is usually poor anyway). The wide filters in the AM receiver may be unable to eliminate the nearby (in the same box!) retransmission on the 2m band.

You might try the 70cm side as the output frequency, as a test, but that still would not make it legal.

Bob WB4ETT

 

[H0LLYW00D]

The only problem with using a 70cm band output is that my handheld only works on the 2m band.

 

[4RunAmok]

You don't need a 70cm HT to hear the radio operate correctly, the multitude of clicking will stop. Or, try tuning a 70cm freq with some traffic on it, and crossband repeat that to the 145.000

But right now, you're just "band repeating", and the radio isn't capable of it. CROSSband means one band on one tuner, another band on the other.

 

[gary in ohio]

Keep in mind even if your using just the ham bands the yaesu 8900 cant do legal crossbanding. The radio, nor the user have the ability to properly ID the the 2 transmitters in use.

 

[H0LLYW00D]

Just to confirm the 8900 is unable to act as a repeater? Now I am even more confused as this was one of the reasons I bought this radio so that it can't act as a mobile repeater

 

[gary in ohio]

Just to confirm the 8900 is unable to act as a repeater? Now I am even more confused as this was one of the reasons I bought this radio so that it can't act as a mobile repeater

The problem is most people use the "cross band" repeater function incorrectly and and end up operating a illegal station. First is IDing the transmitters. In cross band mode there are 3 transmitters you need to be concerned about The transmitter from your HT to the mobile, The mobile to the remote station and the mobile back to your HT. Simply IDing takes care the HT-mobile link, there is mixed opinions if that also can be used to legally ID the mobile to remote.
Now the big gotcha is how do you ID the mobile to HT link? The answer is you cant, this in iself makes the cross band system illegal.

Second issue, All stations must have a control operator that take control of the station and shut down the transmitter remotely. Most of the current crop of cross band radio DONT have this function, some will argue that if your "close" to the transmitter that close enough. If you just running into the mall and carrying your HT to listen to the repeater while your inside I might go along with your "close enough", but if you leave your radio un attended for any time period or get a significant distance from the mobile then your in violation of FCC rules.

even if you ignore the all the issue above you have the issue of what bands you can link on. To be legal you must have the HT on UHF and link to VHF, The other way around is not legal. FCC rules only allow linking on 220mhz and above.


The proper way to use a "cross band" repeater is to use it in an extender mode. use a dual band HT, Set the HT up to transmit on UHF and receive on VHF. the Radio is setup to recieve on UHF and transmit on VHF.

So you use your HT to hear the remote station on VHF and use the HT to transmit to the moble and on to the remote station. this works fine for repeaters but not so well for simplex stations. Using this way you ID all your transmitters

 

[H0LLYW00D]

I got a friend to use his radio and we setup another crossband and still had the same results, just a clicking when the mic on either end is keyed. I have done a full reset on the unit and still no change. Going to take it make to the dealer to see if it is a hardware problem.