Wildrose NetworkHow to Cross Band on DStar and DVAP using an Icom 2820 (2) and
        a Digital Handheld
... and now on Yaesu System Fusion using C4FM

June 17/15

C4FM Cross Band    

It's been almost 6 years since we started cross banding on DSTAR.  Now that Yaesu Fusion System is out can we cross band C4FM.   The answer is YES.   A little complicated in the beginning, it turns out to be quite simple, more so than DStar. 

On my mobile, in this case the same radio I use for DStar cross band (Icom 5100) I use the same simplex frequency and FM mode I use for my connection to my handheld on UHF.  On the VHF side just use the repeater frequency including offset, do not enter or use any PL.    Put your mobile radio into cross-band mode.  (Be sure to set power levels and maybe turn down your volume on both sides and set squelch levels to Max if possible to prevent unwanted signals from getting into the radio since there is no PL) 

Now the only extra thing I did on the portable (FT-1DR) compared to DStar is to save my remote frequency into memory including the PL tone of the repeater you want to operate. 

When using the portable you can use all modes including Digital, Data and FM.  The radio knows not to send PL when in digital mode so all modes will work through your mobile radio using your handheld.  All information from the handheld is sent through your mobile and off to the repeater including GPS location and modulation mode.  Even receiving the GPS data and different digital modes from the repeater through your mobile will make your handheld switch to that mode if set to auto.   Basically the C4FM works the same as if you were working your C4FM repeater direct.  If your repeater is on UHF just do the opposite of what I have describe.

I have been using the Icom 2820 for many years cross banding on DStar and now using the newer 5100.  I recently tried it using my FT-1DR portable and it works just fine.  So I would suspect any FM dual band cross banding radio should work.  I do have the FTM-400 mobile version but I find it awkward putting it into cross band mode so I just use my Icom 5100.

A word on the FTM-400, it does work for C4FM with your FT-1DR just make sure auto mode on the mobile is off and as I have describe above should work.  However if you try DStar using the FTM-400 I have found issues,  Right now I would have to say that DStar will not work using this radio.  Further testing may change that.

If you have any comments or other ideas I would like to hear from you.  Just email me at:  ve6cpk@shaw.ca

DVAP Cross Band    Last July 4/2010

I have found that the DVAP unit will work cross banding through my 2820 but there are some minor issues:

     - on the DVAP be sure to run the latest firmware (1.05).  Latest version has solve many issues from earlier versions.

     - when cross banding through your 2820 your portable must be simplex, having an offset will not work (remember before we needed an offset on our portable to make it work - see below).
     - also I have found that there is some inconsistencies usually when you change parameters like linking or unlinking, even doing an echo test. Once connected it usually works OK.  If your trying to unlink after a QSO with someone I find that it may take 3 or 4 key downs to make the connection unlink.  In the meantime your still connected and that transmission your making trying to unlink will keep keying up whatever you were linked to. This could be due to the 2820 not keying up quick enough however your mobile may be different than mine.  You will have to try and experiment with this.
     - another thing to maybe note is that I have found that to much power from the mobile radio to the DVAP sometimes will not allow the DVAP to send data to the internet.  I think that the DVAP not being shielded gets overloaded from to much RF close by.  I have occasional noted this even from my handheld when sitting to close to the DVAP beside the computer.  Moving away a few feet usually solves this problem.  Same with the mobile, be sure to be a few feet away and make sure your TX to the DVAP is on low power.  The UHF side from the mobile to you can be whatever power you want to run.

It does work but patience may be needed when changing parameters.  I would appreciated any email (address at bottom of page) from DVAP users that have tried cross banding and tell me how it works for you.  When  using this method the range is well extended using your Icom 2820.

Jul.4.10  I finally got around to trying the cross band with the newer version 1.05 of DVAP and I have to say for me it is working a lot better.  Very seldom do I have a transmission that does not go through.  This certainly gives me a lot more range than what the DVAP is capable of.  Just follow the steps above for settings and you should enjoy much more range.

DStar Cross Band - updated Dec 31/09

     I just recently discovered how to crossband on DSTAR using a simplex frequency rather than a duplex frequency as described earlier, however your portable radio still needs to have an offset setting either + or - then zero out that offset.  This has to be done only on your digital handheld, the 2820 can just be simplex.  To make the DStar repeater work the portable radio must look like there is an offset to the repeater but zero-ing out that offset will make it work as a simplex channel.

      - see below for more details
irst in the Digital Setting Menu make sure that Digital Monitor is set to Auto.  Any other setting will not work properly.  On the left side dial in the VHF repeater frequency and leave it in FM mode.  On the right side dial up a UHF frequency (**NOTE this frequency can be simplex, no offset required - see below for portable settings) and also leave this in FM mode.  Set other settings like power and squelch to what you need then put the radio into cross band mode.  (Squelch settings I would set to Max, see below for comment)

How to put the radio into ctross band mode:

Hold in the two main band knobs and then push and hold the function key until the radio beeps.  You should then see the lock symbol flashing, this indicates you are in cross band.  To get out of cross band simply push and hold the function key for a second or until the radio beeps.

     Now with your hand held program in the UHF frequency that you selected on the 2820 and put your portable into DV mode (Just remember that this frequency must have a programmed offset for working the DStar repeater but you can zero out that offset to make it work as a simplex frequency).
You can also use low power setting in most cases from your hand held to the car giving you a lot more talk time if required.  Program all other parameters just like you would normally do for DSTAR including RPT1, RPT2 and UrCall.  You can certainly store the info in a memory channel for quicker access. 

Before walking away from your vehicle you can do an ECHO test to make sure that you have a good signal to the repeater and have no R2-D2 and also to make sure your setup is working.  Being that DSTAR has no hang time as do most FM repeaters you can access the DSTAR repeater just as quick as the next person.  I have found the transistion to be very quick.
Here is a image of my 2820 and 91AD when in cross band node.  Click on image to make it larger.  2820 cross band 
On the portable even though I am using a simplex frequency note the + offset symbol on the display (just above the DV setting).  If that + or - symbol is not there you will most likely not key the DStar repeater.

I had another ham do the same, we had 2 hand helds, 2-2820's and the repeater with no compromise at all.   You really cannot tell that there is any repeating going on besides the repeater itself. 
Maybe in one of your messages you might want to indicate that you are cross banding.  I recently noticed on one of the nets a message indicating "Crossband /2820"/where after his callsign was /91AD.

Squelch Settings:

I have found one issue so far and that is to make sure your squelch levels are set accordingly.  If local noise were to key your radio (2820) an FM transmission would be made on the repeater input.  This will not key a DStar repeater but having a signal on the input may prevent other users from working the repeater.  Some more experimenting may be required to solve this issue.  So far for me I have had no issues, I usually make sure my squelch settings are set at max on both sides.  Volume level does not matter where it is set at.


I have just tested the 2820 with just a simplex frequency to talk to the portable, no offset is required.  You just need to set the offset on the portable only and zero out that offset.  This is required in order to key up your DStar repeater via the 2820.  You can certainly use a duplex channel if required but this is best if your the only one working the crossband.

There are advantages to using a simplex frequency rather than a duplex, say your at a coffee shop using the DStar repeater, everyone is on simplex and can hear all other users and can also hear and work the repeater.

I have heard others wondering if a plain FM dual band radio would work.  I had thought of that and actually gave it a try using a Kenwood 700 and a TS-2000.  The answer...NO.  I believe that the Icom 2820 is actually relaying in DVmode where the other FM radios are only relaying in FM mode and FM will not key a DStar repeater.  Also there is a band width issue.

I spent some time recently trying different methods of codes (PL/DCS) on the RX side of the 2820.  When doing so I could not get the radio to key the repeater and in some cases could not get the 2820 to cross band when in DV mode on the portable.  I have the feeling this will not work so...make sure your squelches are where you need them to prevent accidental keyup of your 2820.

If you have issues with noise keying up your radio when in cross band mode try this, activate the attenuator built into the radio.  You can vary this to some degree and this may help reduce unwanted noise and keyup of your radio.  I have not tried this as it has not been a issue for me but another ham here in Calgary has, VE6BGZ and it seems to work for him.

I have not tested this but I heard that another ham tried the above procedure in reverse from VHF to a UHF repeater and the same procedures apparently do work. It is critical that you have programmed in a offset on the portable otherwise you may not key up the repeater.  If you are just extending your DStar simplex range then the offset is not required.

I'll add further notes here as I find them, also if you have any please let me know.

If you have any questions or if you have some other uses or ideas of cross banding I would really like to hear from you even if it's just to let me know how the cross banding is working for you.  Please email me and let me know at:


Enjoy!!!   73...

Dale / VE6CPK
Admin / VE6WRN
            Counter by Digits

What others have had to say...

Has anyone been successful with crossbanding the DVAP with a non dstar radio, like the d700 or d710?
Rich W0RWC

Yes... I have done it with an Alinco DR-635T.
The Alinco simply passes the digital voice without any decode or encoding, so the audio is straight through. Works a treat.