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VFE Bumblebee

Started by jimilee, June 29, 2020, 07:46:38 PM

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jimilee

Here's the breakdown. I wanted to support Peter Rutter, so I paid the 10.00 to get his files. Even though I could get a Bumblebee board from Brian, I paid 22 for 3, I don't know why. The fix was in the 5457, the trick is the calibration.








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Pedal building is like the opposite of sex.  All the fun stuff happens before you get in the box.

cooder

Super cool Jimi, great graphics! Has a sting to it...  ;)
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alanp

That is a busy, busy board.
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benny_profane

Glad to see you got it sorted out! Where'd you end up getting the JFET that worked for you?

jimilee

Quote from: benny_profane on June 29, 2020, 09:15:15 PM
Glad to see you got it sorted out! Where'd you end up getting the JFET that worked for you?
Ended up getting it from someone here. Your best bet is just to go on eBay and buy a bunch (now than 5) from someone in the states.


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Pedal building is like the opposite of sex.  All the fun stuff happens before you get in the box.

benny_profane

Quote from: jimilee on June 29, 2020, 09:55:31 PM
Quote from: benny_profane on June 29, 2020, 09:15:15 PM
Glad to see you got it sorted out! Where'd you end up getting the JFET that worked for you?
Ended up getting it from someone here. Your best bet is just to go on eBay and buy a bunch (now than 5) from someone in the states.


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Good advice. I'm set with TH JFETs for a while and have been moving toward SMD JFETs anyway...I was curious because that seemed to be the sticking point in your troubleshooting thread.

jimilee

Quote from: benny_profane on June 29, 2020, 10:10:56 PM
Quote from: jimilee on June 29, 2020, 09:55:31 PM
Quote from: benny_profane on June 29, 2020, 09:15:15 PM
Glad to see you got it sorted out! Where'd you end up getting the JFET that worked for you?
Ended up getting it from someone here. Your best bet is just to go on eBay and buy a bunch (now than 5) from someone in the states.


Sent from my iPhone using Tapatalk

Good advice. I'm set with TH JFETs for a while and have been moving toward SMD JFETs anyway...I was curious because that seemed to be the sticking point in your troubleshooting thread.
Yessir. Do the 5457 smt jfets vary in hfe? I know in the 201s, they tend to be pretty steady and kind of high.


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Pedal building is like the opposite of sex.  All the fun stuff happens before you get in the box.

benny_profane

Data sheets and the analysis in the link below  have all the info you need.

http://runoffgroove.com/fetzervalve.html

I've found that the SMD parts are generally more consistent. The specs are the same as the TO-92 devices, but they are still in production and haven't been sorted through already.

jimilee

Quote from: benny_profane on June 30, 2020, 12:06:41 AM
Data sheets and the analysis in the link below  have all the info you need.

http://runoffgroove.com/fetzervalve.html

I've found that the SMD parts are generally more consistent. The specs are the same as the TO-92 devices, but they are still in production and haven't been sorted through already.
Very cool. If I can get them in various Hfe then I am going to grab 20 or so.


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Pedal building is like the opposite of sex.  All the fun stuff happens before you get in the box.

pierre67

Very nice buil !
...is it possible that you have the optocupler reversed?

jimilee

Quote from: pierre67 on July 19, 2020, 11:12:10 AM
Very nice buil !
...is it possible that you have the optocupler reversed?
Nope, any other way and the two trannies above it get the wrong voltages. The dot is where it's supposed to be.


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Pedal building is like the opposite of sex.  All the fun stuff happens before you get in the box.

Cybercow

JimiLee - so glad you finally got it working. Looks great!
Cybercow - aka: Mark Davis

"Don't let your talent take you where your character can't keep you."

jimilee

Quote from: Cybercow on July 19, 2020, 03:39:54 PM
JimiLee - so glad you finally got it working. Looks great!
Thank you. You gotta have the right 5457. It was affecting the voltage and I dont'know why. It was a bear, that's for sure.
Pedal building is like the opposite of sex.  All the fun stuff happens before you get in the box.

Cybercow

Quote from: jimilee on July 19, 2020, 03:49:18 PM
Quote from: Cybercow on July 19, 2020, 03:39:54 PM
JimiLee - so glad you finally got it working. Looks great!
Thank you. You gotta have the right 5457. It was affecting the voltage and I dont'know why. It was a bear, that's for sure.

JimiLee - FETs are a fickle device. Kinda like NOS germanium trannies in that the specs can be all over the map for any given part number. When ever applying FETs, I always socket them because it can be a crap shoot selecting them. Even with a Peak Atlas DCA75 to pre-test (measure) them, they can be fickle. Still, happy to see this done.

How do you like it? Is the swell dramatic or  . . . . . ?????
Cybercow - aka: Mark Davis

"Don't let your talent take you where your character can't keep you."

danfrank

Jimilee you're killing me here! What's the correct specs for the 5457?!? What the build doc says??
Lol