Road Rage question

[catfud]

I'm wondering whether I'm being a total noob and have been misunderstanding the Road Rage - I've been trying to use it to switch between different voltages, but have been running into problems.

Is the Road Rage intended to supply a single voltage only - i.e. to be partly populated according to whether you want -9 *or* 15 *or* 18 volts from a single board? I've fully populated a Road Rage with the intention of switching between the different voltages on-the-fly, expecting all voltages to be available from the respective pads, but the pesky voltage isn't behaving the way I was expecting/hoping.

Feel free to slap me with a metaphorical wet fish if I've got the wrong end of the stick...

[RobA]

Each voltage output is always available on a fully populated RoadRage. Before I built a multiple output power supply, I used a RoadRage exactly that way to work on breadboards. I didn't ever do live switching, but I can't see how that would matter since the switching should be after the RoadRage outputs.

I think it should work so, maybe more of a description of how you are using it what's going wrong would help figure things out.  Also, maybe some photos would help.

[madbean]

It's possible it will misbehave if your current draw, i.e.what you are supplying, is too high. The MAX1044 taps out at about 20mA and the LT1054 at about 40-50mA, I think.

What kind of voltage readings are you getting, and are you taking them with no load (IOW not connected to anything)?

[catfud]

Thanks for the replies!

Each voltage output is always available on a fully populated RoadRage. Before I built a multiple output power supply, I used a RoadRage exactly that way to work on breadboards. I didn't ever do live switching, but I can't see how that would matter since the switching should be after the RoadRage outputs.

I'm relieved, thanks. I'm planning to use a break-before-make rotary switch for switching the DC when I get it working.

What kind of voltage readings are you getting, and are you taking them with no load (IOW not connected to anything)?

I was getting erratic voltage readings, and was taking the readings with no load. It would work for a few seconds, and then stop working.

I depopulated half the board, following up the theory about using it for a single voltage, and lifted some of the pads in the process, so it's now an 18v only Road Rage.

Anyway, following further testing where I still wasn't getting voltage, and couldn't understand why, I picked up the 9v battery I was testing with, and found it to be hot... I had some intermittent shorting on the base of the board that I just couldn't see. After running my iron between all the pads (probably not best practice) and cleaning up the board it started working again.

The upshot: I plan to clean my populated boards after soldering in future. (note to self: order some more road rage boards)

[catfud]

Update: I built another fully-populated road rage last night and this time with no shorts (the board, not me), all voltages work perfectly, as hoped! Happy days!