Griffin Ricochet (Surfy Bear Clone) Issues

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Brandalones

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I just finished a build of the Griffin Effects Ricochet (https://griffineffects.com/byo-pcbs/modulation/ricochet-pcb) using the original mixer, and am getting power and signal in both bypassed and on positions, but when on, I don't get any reverb, only like a fuzz when dialed wet. No crash sound if I shake the springs either. I had the TP1 getting voltage at about 6.6 after adjusting R13. I also read on another post that someone tried removing Q3 - BC557B so I also did that. No real change.

Any ideas what else could be the issue? My only thought is maybe one of the MOSFETS are fried, but I am getting voltage readings on both of them. I don't know what they should be reading at each pin though.

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Locrian99 said:
You guys got any pics if your pedals? I got this one on the way and im debating the tank set up. Right now im leaning towards just mounting the tank to a piece if wood large enough to velcro the pedal to
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the surfy I built is in a tool box because I used the long two spring tank. the ricochet was in an ammo can with the shorter three spring tank. frame of reference, the toolbox will fit a full size amp head, the ammo can will fit the smaller "lunchbox" size like the OR15.
 
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Locrian99 said:
You guys got any pics if your pedals? I got this one on the way and im debating the tank set up. Right now im leaning towards just mounting the tank to a piece if wood large enough to velcro the pedal to
Click to expand...
I haven't housed mine yet, but I have another one going to a friend, and he already built an enclosure that's slightly smaller than a Fender 6g15 unit to mount his in. Mine will be closer to the SurfyBear form factor.
 
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Big thanks to ITC and Earl...replaced R15 with 1.5R and lo and behold I have reverb. Q4 and Q5 are hot. Voltage at the TP1 is about 8 volts, so I need to adjust the value of R13, but headed in the right direction now. Thanks again!
 
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For MOSFETs, it is necessary to install additional heatsinks so that they do not overheat. By changing R15 to 1.5 Ohm, the BIAS current becomes 400mA, which results in a power loss of 0.4Ax6V= 2.4W on each transistor at the set 6V center voltage. Therefore, it is necessary to conduct 4.8W of heat to the surroundings, for which the copper polygon on the printed circuit board is insufficient. I suggest an Aluminum L profile that is screwed to the metal housing. Of course, it is also necessary to take care of the electrical insulation between the transistors housings and the aluminum.
 
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Brilliant thread! Thanks mondxxi for solving this problem for so many here. I'm here doing a bit of research before taking the plunge on this myself.

I'm a little mystified as to what heatsinks for the fets would look like. Would anyone care to share a pic or two?
 
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Mickeyg said:
Brilliant thread! Thanks mondxxi for solving this problem for so many here. I'm here doing a bit of research before taking the plunge on this myself.

I'm a little mystified as to what heatsinks for the fets would look like. Would anyone care to share a pic or two?
Click to expand...
if you google image search surfybear diy you'll see what they used to use. here's an example that does not belong to me.

2nuuPzjoTm2bAjW6KMs2ow.jpg
 
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Mickeyg said:
Brilliant thread! Thanks mondxxi for solving this problem for so many here. I'm here doing a bit of research before taking the plunge on this myself.

I'm a little mystified as to what heatsinks for the fets would look like. Would anyone care to share a pic or two?
Click to expand...
Using the enclosure as a heatsink would have been wise but alas.
They're also kind of close together which limits your choice.
From tayda, these have the most mass
www.taydaelectronics.com

Heat Sink TO-220 14 Fins 25mm Aluminium Black

Get It Fast - Same Day Shipping
www.taydaelectronics.com www.taydaelectronics.com
But not sure you'll get 2 to fit or if there's vertical room.
ICTRock said:
if you google image search surfybear diy you'll see what they used to use. here's an example that does not belong to me.

2nuuPzjoTm2bAjW6KMs2ow.jpg
Click to expand...
I think the PCB layout is too tight to allow those.
 
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