RGW Electronics Bad Bob Gut Shots  [traced]

General documentation, gut shot, schematic links, ongoing circuit tracing, deep thoughts ... all about boutique stompboxes.
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sinner
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Post by sinner »

I know it's J.Orman's MiniBooster variation, but I wonder what changes was made according to original design... I've got only one gutshot picture of it taken (borrowed - I'm sure Mike Piera have nothing against) from analogman's website (added to the switch box)

It looks like there is one 1uf cap (The input dc blocking capacitor??) and lot less parts than in Jack's Minibooster. Anyone have more picts of it? The one on AM page sucks big time, to low quality...

Image

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Post by Bernardduur »

I think it is this one......

Maybe the 1u is instead of the 3u3
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Post by salocin »

Here's top side shot for anyone confused like I was:
Image
Details at http://www.analogman.com/switchbox/index.htm

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Post by sinner »

Actually this is the one http://www.analogman.com/badbob.htm

The gutshot I've added is the only one I've got. AM added it to the switcher he made

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Post by MoonWatcher »

sinner wrote:I know it's J.Orman's MiniBooster variation, but I wonder what changes was made according to original design..
Probably the bigger question to ask is what changes did AM make to the BB now that they aren't being made by RGW?

AFAIK, the original BB's were built chapter and verse to Orman's design, after RGW had many lengthy discussions with Jack. The most notable difference being that the transistors were tested and sorted, due to variation - something that I'm not sure that AM will be doing. Or could practically/realistically do, simply because of the number of pedals that are built.

Some will argue that there isn't really much that you can "tune" with the minibooster circuit. That said, I've heard a few of the original BB's and they all sounded very good to me.

I guess that the easiest thing to do would be to compare the AM version against Jack's original schematic and determine what is missing.

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Post by Old Gregg »

I cloned the exact circuit from Robbie's first lot of builds from the GGG PCB ( I had #7), I'll get a gut shot up when I get the chance.

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Post by sinner »

Old Gregg wrote:I cloned the exact circuit from Robbie's first lot of builds from the GGG PCB ( I had #7), I'll get a gut shot up when I get the chance.
Smashing! Thank you :hug:

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Post by Old Gregg »

Here tis, it's built on the GGG board, exactly as RGW did his first 10 or so,
the only difference being I have it on a 3 pos switch to choose different gain amounts
(found it easier when changing from a strat to a LP)
And the original jfets were 2n5457, I used J201's as they suited my amp a little better.

Image

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Post by sinner »

Here's BBB on ebay

I'm adding pict from the auction. Not a lot to see, blury picture, at least resistor values can be copied

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Post by sevinisthenumber »

Repaired the battery clip on this guy the other day and grabbed some shots.
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Post by Cannibal »

just guessing but it looks like an amz mini booster if you those transistors are FETs
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Post by Cannibal »

Cannibal wrote:just guessing but it looks like an amz mini booster if you those transistors are FETs
i meant: i'm just guessing, but it looks like an amz mini booster if you confirm that those transistors are FETs.
sorry for the horrible sentence but i'm reading in spanish, speaking italian and typing in english, one of the three had to be wrong at least in one point.
Seiche wrote:there's a difference between being drugged (I don't think it was only booze) and retarded.

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Post by sevinisthenumber »

Cannibal wrote:
Cannibal wrote:just guessing but it looks like an amz mini booster if you those transistors are FETs
i meant: i'm just guessing, but it looks like an amz mini booster if you confirm that those transistors are FETs.
sorry for the horrible sentence but i'm reading in spanish, speaking italian and typing in english, one of the three had to be wrong at least in one point.
Ha! No prob! They are 2n5457's
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Post by devastator »

Cannibal wrote:just guessing but it looks like an amz mini booster if you those transistors are FETs
no need gessing , it's a mini booster :roll: (you have just to look at the trace to see that).

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Post by Ice-9 »

I know this is an old thread but I just wondered if the Bad Boob uses a 1uf or 3u3 cap in across the gate/source of the upper jfet. Jacks AMZ booster used the 3u3 but i'm not sure of RGW or Analog mikes version.
It's fairly straight forward, if you want to start it , press start. You can work out the rest of the controls for yourself !

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Post by Kap'n »

Old Gregg wrote:Here tis, it's built on the GGG board, exactly as RGW did his first 10 or so,
the only difference being I have it on a 3 pos switch to choose different gain amounts
(found it easier when changing from a strat to a LP)
And the original jfets were 2n5457, I used J201's as they suited my amp a little better.
Necro-post, I know.

I used a Mammoth kit to try to clone my BBB (#39) - matching and removing parts from the kit. I found that J201 sounded a lot closer to my original than when I used the extra 2N5457 transistors I purchased. I don't know a lot about transistors. Any thoughts?

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Post by MoonWatcher »

Kap'n wrote:
Old Gregg wrote:Here tis, it's built on the GGG board, exactly as RGW did his first 10 or so,
the only difference being I have it on a 3 pos switch to choose different gain amounts
(found it easier when changing from a strat to a LP)
And the original jfets were 2n5457, I used J201's as they suited my amp a little better.
Necro-post, I know.

I used a Mammoth kit to try to clone my BBB (#39) - matching and removing parts from the kit. I found that J201 sounded a lot closer to my original than when I used the extra 2N5457 transistors I purchased. I don't know a lot about transistors. Any thoughts?
Was always under the impression that J201 was used in the RGW pedals.

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Post by Kap'n »

Mine has 2N5457 and a third-party board. Maybe he switched later? In any case, I just found it curious that the J201 sounded more like my original than the transistors that had the same code.

I'm having a heck of a time posting - I don't stay logged in.

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Post by matt239 »

Any difference from mini booster?
- Different values, omitted / added parts?

Just curious.

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