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My wife and I often enjoy taking our three dogs to conservation areas and woodland trails, especially in the cooler months when the dogs don’t overheat and we’re not fighting off insects or for trail space.

The Bruce Trail is one of the most popular trails in the province, and it also happens to cut through one of our favourite conservation areas known as Silver Creek. This area hosts a half dozen trails in addition to the Bruce Trail and they all vary from steep heavily forested woodlands that rapidly descend and ascend, to open meadows and flat farmland.

While the trails are very well maintained, in the cool season they are very quiet and it’s not uncommon to walk for an hour or more without seeing anyone. In addition to the quiet nature of the trails, there are many hazards such as snow, ice and sometimes mud in the late fall and early spring.

While these hazards are expected and anticipated there’s always a small risk of a slip and fall and an even smaller risk that that this fall could become serious where medical attention is needed. While the risk is tiny in my opinion, it is not a non-zero risk and I do sometimes head out alone with just one furry companion.

Due to the variable nature of the trails and the heavy forest, cell reception is marginal at best and largely non-existent, especially in the areas which would pose the greatest fall risk to anyone hiking through.

My solution of course is to keep my hand held radio on my person and connected to the club repeater. Not only does this offer at least some security in knowing I can raise someone if needed, but I can also chat with fellow radio operators while on the trail.

Unfortunately given that Silvercreek is 42km from the VE3SKY repeater, it’s virtually impossible to reliably hit the repeater with a handheld radio let alone key it. Fortunately, this is where crossband repeating with a mobile radio really comes in handy.

The Trail Head where I often park is a high point and with a little bit of fine tuning (driving forward and reversing) I can get into the VE3SKY repeater very well with only 15 watts from my Icom 5100. Conversely, with only 5 watts on the UHF side of the mobile radio, my FT-60 hand held transceiver has excellent reception with the stock antenna. Running the FT-60 at the high power setting of 5 watts provides 2km of direct reliable range through the trees, hills, valleys and all around the trails. I could increase the power output of the Icom 5100 to 15 watts on the UHF side but while my portable reception would undoubtedly increase (I would hear the mobile repeater more clearly), I would have a harder time guessing where the vehicle repeater cannot hear my hand held all that well due to the power disparity.

A caveat with crossband repeating radios is that they are not intended for 100% duty cycle and running them at full power on both sides of the VFO can heat them up quickly, especially if you start having a good rag chew. Running lower power is always the best option to preserve the life of the radio, and a well sited cross band repeater/radio should function well with only 5 watts for most all practical applications.

Now in order to keep the mobile radio powered without draining my vehicles battery, I utilized a 40AH battery box that I built using two SLA batteries, a bunch of components from Amazon.ca and of course a $20 ammo box from BassPro Shops.

The 40AH battery box provides a conservative 400 watt hours of run time which means, in theory, I could run the Icom 5100 for 26 hours continuously transmitting at 15 watts. Obviously theory and practice don’t always line up so smoothly, but even if we half that time, it’s still 13 hours and again that’s assuming the radio is transmitting for 100% of the time. In a practical sense with this setup I could leave the radio in crossband repeat mode for literally days before the battery is depleted.

The last consideration that I had to look at was using tone squelch to prevent any spurious noise from keying the radio while I’m away hiking on the trails. Some radios such as the Yaesu FTM-300DR have intelligent signal processing meaning they will strip tones from an incoming signal before re-transmitting it and/or applying a new and/or different tone. This means with the FTM-300DR I have the option of using digital code squelch (DCS) on the UHF side of the VFO (which I’m a huge fan of) while maintaining a traditional tone squelch on the VHF side for the VE3SKY repeater.

Unfortunately, the Icom 5100 does not have signal processing. This means tones will not be stripped from a signal before re-transmission and therefore two different tones may conflict with one another such as a DCS and analog tone.

In order to prevent a conflict, I used tone squelch on my FT-60R, and just used an output tone of 103.5 to match the repeater. I then set tone squelch on the 5100 to receive only using the 103.5 tone on the UHF frequency and did the same on the VHF side of the VFO for VE3SKY.

This meant I would not have a duplicate tone in the crossband repeating process, the tone from my handheld would pass through the radio and open the repeater and the repeater tone would pass through conversely opening my handheld. The Icom-5100 therefor only listened for tones but never applied any, it only passed a signal that was already present.

Once the Icom 5100 was in crossband mode and I confirmed everything was working, Biscuit and I headed off for our hike on the Bruce and several other trails. While hiking I spoke to a number of Skywide club members. Robert (VE3VAJ) and I carried a conversation for the first few kilometers of the hike and Walter (VE3WJO) carried on a good conversation for last few kilometers. I also briefly spoke to Dan (VE3MA) closer to the vehicle.

The QSO on the trail with fellow club members was nice and it served as a good technical test to see just how well everything worked. Even in the deepest of the valleys VE3VAJ reported no issues hearing me or passing traffic. The same was true of VA3WJO who only reported a few instances where I had less than ideal signal reports.

Crossband repeating is a powerful and relatively simple way to bridge the gap between your favourite repeater and handheld radio whether you’re at home, or out and about.