Issue with Rangemaster Board

[DPM309]

Purchased the last Rangemaster PCB a couple of weeks ago and could not get it to work initially. Something was grounding out the circuit causing only hum and battery got extremely hot in a few seconds.  I double and tripled checked everything and narrowed the problem to either D1 and R3.  Pulled out both and the board was still grounding out.  I had to scrape around the pads on the bottom of the board (not the grounded side of these components) so that they were not touching the ground plane.  It was not a solder bridge since I had to scrape the copper away from the pads.  Don't know if this was a problem with the board, but after I isolated the 2 pads from the ground, the unit works fine.  Don't know if anyone else has run into this before.

[blearyeyes]

I had to do the same with a trace/pad on a Colosulus. Did you do any de-soldering on those pads?

[DPM309]

Yes I de-soldered the diode pad but was very careful when I removed it.  Cleaned the pad up with solder wick, etc. Was still getting the short after that. Maybe the extra heating up of the pads caused the short to the groundplane? I also built an identical Rangemaster using Vero Board since I grabbed up the last MadBean PCB.  The VB Rangemaster worked perfectly.  Still having some issues with hiss on the MadBean one.  Once I get this resolved, I will do a side by side comparison of both Rangemasters.

[DPM309]

Both pedals are working fine but I am still getting some static/hiss from the MadBean board when it is turned up past halfway. Same results using a battery or a 9V positive ground power supply. Tried chopsticking inside the pedal with no luck.  Any suggestions on how to get rid of this?  I used identical components for both and am getting virtually no static/hiss with the Vero board.

[midwayfair]

Same transistor in the vero build? Some transistors are noisy.

[DPM309]

Yes, I am using the OC44s that I purchased from Pedal Parts plus.  They are new stock. Used 2 with similar hfe readings.

[DPM309]

When I added the Rangemaster to my pedal board, the LED does not light up and I get a thumping sound.  Also, I get no power to rest of the pedals.  I am using a One Spot with a daisy chain cord.  When the RM is connected by itself it works fine. When I daisy chained both RMs to the One Spot, both pedals worked fine. I also ran a separate 9V positive ground supply to the RM with rest of the pedals connected to the One Spot and it works perfectly.  Read something somewhere about the Rangemaster needing an isolated, positive ground 9V supply.  Am in the process of building a power supply with 8 isolated outputs for my pedal board, using a Weber transformer, so this will not be a problem but am still wondering if this is normal.

[midwayfair]

You're trying to power a PNP pedal with a negative ground power supply. When you plug it in, you're connecting the +9V to ground. That's why it's not working. You need a battery or a polarity reverser for the rangemaster -- something like the roadrage.

Also ... this is a lesson to read the build documents carefully. It's on the first page, in giant letters: This is a positive ground effect.

[DPM309]

The One Spot is a positive ground power supply.