WIRES-X vs. YSF vs. FCS vs. YCS

One of the biggest questions for hams entering the world of hotspots is the all the CONfusion with System Fusion. What is the difference between WIRES-X/YSF/FCS, and how do you connect to a WIRES-X Room with a hotspot? Time to demystify this.


First off, WIRES-X is Yaesu’s mechanism for linking multiple repeaters together, either done with direct connections or with the repeaters connecting into a room. Repeaters can be connected to WIRES-X either with an HRI-200 connected directly to the repeater, or with a remote rig with an HRI-200 connected to it. Additionally a regular mobile rig type radio could be connected to an HRI-200 to make a remote base (the same could also be accomplished with a mobile radio in PDN mode, but that is beyond the scope of this article).

Yaesu put a lot of work into making the WIRES-X system, and to be honest I think it’s one of the better repeater linking systems out there. To maintain the integrity of the system, however, Yaesu has locked down the WIRES-X system, meaning the only way to get into WIRES-X is with Yaesu equipment.


While the locked down approach from Yaesu does make sense, a few hams in the UK and Germany wanted to see an open source alternative. Two such alternatives were born.

FCS is a centrally located System Fusion reflector service. At the time of writing there are five FCS servers with 99 modules each. Also created was YSF, which is similar in concept except the reflectors de-centralized and hosted by individual hams. Both work essentially the same way, with the caveat being you cannot connect to them via WIRES-X; you need to have a personal hotspot to use it (whether it be an OpenSpot or Pi-Star hotspot).

Connect to WIRES-X on a Hotspot?

So this comes back to the question I see asked all the time, How do you connect to a WIRES-X Room with a Hotspot? And the answer is, you can’t. You can only connect to FCS or YSF reflectors.

Where the confusion comes in, is when people hear other stations on a WIRES-X net saying they’re coming through a hotspot. That despite me just saying this wasn’t possible. What gives?

What is happening in these cases is someone (presumably the WIRES-X Room owner) has created WIRES-X to FCS or YSF bridge. This is the only way that you can talk through a hotspot onto WIRES-X. Yaesu frowns upon this and actually makes it very tricky to build a bridge.

Take for example the CQ-NODAK WIRES-X Room (#62208) that I manage. I created a WIRES-X to YSF bridge for this room, allowing users to come in on YSF Reflector #62208 (hosted by me in the cloud) and can be heard on WIRES-X. To accomplish this, I had to get an FTM100 (luckily I had an extra one that used to be in my mobile) and put it in PDN mode. This also required computer for it to be used with. Originally, I set a frequency split for transmit and receive into TWO different Pi-Star hotspots, as Yaesu updates blocked the Pi-Star’s callsign decoding for remote gateways, basically meaning I couldn’t use a single Pi-Star on a simplex frequency. I later found that the more expensive OpenSpot CAN do this in simplex much more reliably than two Pi-Stars. This bridge has been working for two years now with great success, but it wasn’t without multiple evenings of frustration trying to get it right.

Hopefully someday there will be a happy medium between the three systems. Until then, this is what we have; WIRES-X requires an HRI-200 or a radio in PDN mode, or you need to find a YSF or FCS reflector that is bridged into the WIRES-X Room of choice. The good news is that lots of the popular rooms have bridges not just only between WIRES-X and YSF/FCS, but also into other modes. If there’s a radio or a mode, there is probably a way to get into your room or net of choice.


Since writing this article in 2020 a new player has come on the scene… YCS. Yes, yet another reflector server. Essentially, it can handle YSF, FCS, and IMRS, which is a newer linking protocol supported in the Yaesu DR2X repeater (but not the older DR1X). Meaning, you can setup one reflector server that does everything! You can also use it as a means of linking to an existing YSF or FCS reflector. Mike N0VZC has done this with YCS311, which has a link into my CQ-NODAK reflector. There is a complete YCS Wiki that explains the whole thing in much better detail than I can, so give that a read to learn more. It still doesn’t fix the hotspot to WIRES-X problem, but it’s a step in the right direction to simplify the System Fusion CONfusion.

Updated March 19th, 2022 to add info about YCS.