Rebote 2.5 polarity reverse protection

[axeman010]

Hi All

Please head my word of warning regarding the Rebote 2.5!!!

This is one of my favourite builds of all time however last night at a gig i managed to kill my faithfull old pedal by reversing the polarity on the supply

Can anybody please let me know what the level of damage is likely to be?

I'm thinking a new 78L05 regulator should sort it out but could anything else cooked in the process


For future protection would it just be case of adding a diode across the power rails ?

Many thanks for any advice.

Axeman

[edd101]

Hi All

Please head my word of warning regarding the Rebote 2.5!!!

This is one of my favourite builds of all time however last night at a gig i managed to kill my faithfull old pedal by reversing the polarity on the supply

Can anybody please let me know what the level of damage is likely to be?

I'm thinking a new 78L05 regulator should sort it out but could anything else cooked in the process


For future protection would it just be case of adding a diode across the power rails ?

Many thanks for any advice.

Axeman

hi,

I had a simmilar situation a while ago. The resul was dead regulator and TL as well

[Fp-www.Tonepad.com]

The opamp and regulator and possibly the 47uF capacitors would need replacing. Hopefully the 2399 survived by standing behind the regulator!

[axeman010]

many thanks for the replies!

I replaced the regulator and the op-amp and the Rebote is now working again.

However after using the rebote  for approx. 30 mins with the the unregulated wall wart the i have always used to power the effect the wall wart appears to have burn out (became very hot and ceased to work). This of course just be coincidence?

Or could it be that something else in the effect has caused the supply to burn out. I relaced the regulator with the following part from maplins and a standard TL072CN

Order  Part             Case  Output      Line 
Code   Number        Style  Voltage V Regulation mV 
QL26D TS78L05CT TO-92  5V           50 


Would damage to the 47uF caps. suggested by Francisco cause this problem.

The Rebote is still working but i have noticed a "thump" when switch the effect on and off.....could this also be related to damaged caps?

Update......"thump" is only there when using a power supply, not with a battery so i guess that is the smoothing caps that have gone then ?

Once again any help gratefully received!

Axeman

[axeman010]

Just as a final update in case anybody else falls foul of this error.

I was the 47uF cap across the power supply which had failed and was causing the "thump" when the effect was switched on. Still not sure if this could cause the wall wart to burn out. When i checked the Cap with a meter it had not shorted which may have caused the problem, so i am open to any ideas on this one.

I would highly recommend that anybody wishing to avoid this happening to their much loved pedal read R.G's article "Advanced Power Switching and Polarity Protection for Effects" on the GEO web site

Regards

Axeman