Mark, yes, the Hobbywing 120A 1S v2.1 is fine, it is on the list along with all the eligible HW speedos
here. Make sure you load the right software so that the red LED (buried in the side of the speedo!) blinks at neutral - that's the one to have to comply with the 'blinky' rule. Got a feeling I'm teaching you to suck eggs now!!
RCDunk, there is a shop that will stock the HW stuff, I just can't remember what it's called!! I'll find out and post again.
I don't want to open old wounds (!) but the HW range of speedos is ideal for this class. I am going to try a Justock at around £40. However, you will need a booster. These work well and are well priced from
AMC. On the HW speedos, set it up with a 2S cell by downloading the 'blinky' software. Make certain that you choose 'no protection' for the voltage cut-off (even unplug it all, plug it in again and check) and then re-set to your radio.
Now, remove the red wire from the receiver plug, and tape it back to the receiver lead so it is insulated. Plug in the booster (it is always on, no switch) and then use the speedo switch to turn the car on and off. Since you don't need to change the software, this works fine. If you want to use the program box, unplug the booster, replace the red wire in the receiver and then do as normal with a 2S cell plugged in. The same procedure applies if you are using a receiver pack. If the receiver pack or booster (e.g. RC Dynamics) has a switch, both switches must be on to run the car. My eternal thanks to Gavin Clinch for telling me how to do this - blatant ad for Gavgrafix shells alert!! - Gav sprays a mean shell...
I know it sounds like a faff, but anyone can do it with the standard booster. There is a better way of doing it (but you have to be able to modify the booster output wires and fit a switch) so that you can use the program box at any time. If someone wants to do that please ask and I'll tell you how. If people think there is a need for a simple solution, I am happy to make up harnesses that will fit the booster directly and plug into the existing system. Please ask; this 2S thing is a bit of a non-event in my opinion, it just needs people to know how to sort out the booster and you're running on 1S.
As always, any of the current LRP and HW speedos that work with a 1S cell will do the job without a booster or receiver pack. HTH
