Sun Coast Amateur
Radio Club Society

User Tools

Site Tools

You are here: home » links » xband
links:xband

Differences

This shows you the differences between two versions of the page.

Link to this comparison view

Both sides previous revisionPrevious revision
Next revision		Previous revision
links:xband [2025/06/26 10:20] – [Repeater Extender] va7filinks:xband [2025/06/26 10:46] (current) – [Repeater Extender] va7fi
Line 4: Line 4:
  
 A crossband repeater is different from a regular repeater in two important ways: A crossband repeater is different from a regular repeater in two important ways:
-  * Where as a regular repeater uses the same band with a small offset between the tx and rx frequencies (600 kHz for VHF and 5 MHz for UHF), a crossband repeater uses two frequencies on different bands (one on VHF and the other on UHF for example). + 
-  * Where as a regular repeater always listens to the same frequency (the input of the repeater) and always transmits on the other (the output), a crossband repeater transmits on one frequency whatever it hears on the other, whichever it hears first.+^ ^  Regular Repeater  ^  Crossband Repeater  | 
 +^1. |Uses the same band with a small offset between the tx and rx frequencies (600 kHz for VHF and 5 MHz for UHF) |Uses two frequencies on different bands (one on VHF and the other on UHF for example) | 
 +^2. |Always listens to the same frequency (the input of the repeater) and always transmits on the other (the output) |Re-transmits on one frequency whatever it hears on the other, whichever it hears first. |
  
 Many higher end dualband radios are capable of doing cross-band repeat (Icom's ID-5100 or Kenwood's TM-D710G are two examples).  Below are different uses for a crossband repeater. Many higher end dualband radios are capable of doing cross-band repeat (Icom's ID-5100 or Kenwood's TM-D710G are two examples).  Below are different uses for a crossband repeater.
Line 14: Line 16:
 The simplest way to use a crossband repeater only works for two handhelds: The simplest way to use a crossband repeater only works for two handhelds:
 {{ links:xband:xband1b.png?600 |}} {{ links:xband:xband1b.png?600 |}}
-  * Here, each handheld uses a different band so there is no need for fancy dual band tx/rx. +  * Here, each handheld uses a different band. 
-  * The problem is that you can't add more handhelds (unless they can already hear the others in simplex).+  * The problem is that you can't add more handhelds (unless they can already hear the others in simplex).  
  
 ==== For more people ==== ==== For more people ====
Line 28: Line 30:
  
 <WRAP center round info 80%> <WRAP center round info 80%>
-But also: look for a menu called something like ''RxMode''  The four options I have on mine are:+But also: look for a menu called something like ''RxMode''.  The four options I have on mine are:
   - ''CROSS BAND'' (uses two handhelds to create a cross band repeater)   - ''CROSS BAND'' (uses two handhelds to create a cross band repeater)
-  - ''DUAL RX RESPOND'' (the radio switches to which ever band it hears for the next transmit)+  - ''DUAL RX RESPOND'' (the radio switches to whichever band it hears for the next transmit)
   - ''MAIN ONLY'' (the radio only uses the selected band so you can't hear the second one)   - ''MAIN ONLY'' (the radio only uses the selected band so you can't hear the second one)
   - ''MAIN TX / DUAL RX'' (the radio only transmits on the selected band, but can hear both)   - ''MAIN TX / DUAL RX'' (the radio only transmits on the selected band, but can hear both)
Line 40: Line 42:
 ===== Repeater Extender ===== ===== Repeater Extender =====
 ==== Simplest ==== ==== Simplest ====
-This is a scheme I use often at home with my base station in crossband mode: I tune one receiver to our local repeater, and the other to a simplex UHF frequency.  I can then use my handheld around the house and the yard with the "power" of my base station and antenna to get into the repeater.+This is a scheme I used to use at home with my base station in crossband mode: Tune one receiver to our local repeater, and the other to a simplex UHF frequency.  Then use the handheld around the house and the yard with the "power" of my base station and antenna to get into the repeater.
  
 {{ links:xband:xband2.png?800 |}} {{ links:xband:xband2.png?800 |}}
Line 53: Line 55:
  
 <WRAP center round important 90%> <WRAP center round important 90%>
-One thing to keep in mind with crossband repeat is that the radio doing the repeating is transmitting every time someone transmits.  Using this scheme to listen to an hour long net means that the radio would transmit at close to 100% duty cycle, which it may or may not be designed to do.  It would be best to use the lowest power setting and/or keep the use to a minimum.+The biggest flaw with this setup is that the radio doing the repeating is transmitting every time someone transmits, which means that the radio could transmit at <fc #ff0000>close to 100% duty cycle</fc>, which it may or may not be designed to do.  So it's best to use the lowest power setting and/or keep the use to a minimum.
 </WRAP> </WRAP>
    
  
-===== Repeater Extender Variation===== +==== One Way Variation ==== 
-The following is a variation I use when I can hear the repeater with my handheld, but can't transmit to it because of the handheld's low power.  In this configuration, the crossband repeater only transmit when **I** am transmitting, not when the others are transmitting, which is much much easier on the radio.+ 
 +The following is a variation I use more often when I can hear the repeater with my handheld, but can't transmit to it because of the handheld's low power.  In this configuration, the crossband repeater only transmit when **I** am transmitting, not when the others are transmitting, which is much much easier on the radio.
  
 {{ links:xband:xband2b.png?800 |}} {{ links:xband:xband2b.png?800 |}}
Line 74: Line 77:
 In this configuration, the crossband repeater only re-transmits Unit A, and not everyone else on the net, keeping the duty cycle low. In this configuration, the crossband repeater only re-transmits Unit A, and not everyone else on the net, keeping the duty cycle low.
  
 +After much experimenting, I found that it's better for the second tone to be digital because a different analog tone sometimes interferes with the repeater's analog tone.  Right now, this is how I setup my frequencies:
 +=== On the Crossband Radio ===
 +  * Band A: 147.**8**20 MHz with a TONE(T)/DTCS(R) tone (it transmits an analog tone and requires a digital tone to open the squelch)
 +  * Band B: 446.100 MHz with a DTCS tone (it transmits a DTCS tone and requires one to open the squelch as well)
 +
 +=== On the Handheld ===
 +  * Band A: 446.100 MHz with a DTCS tone (for transmitting only)
 +  * Band B: regular 147.**2**20 MHz repeater frequency (for listening only)
  
 ===== Repeater Link ===== ===== Repeater Link =====
links/xband.1750958457.txt.gz · Last modified: by va7fi