# Got some "old TV parts" from Russia, looking for suggestions.



## peccary (May 21, 2021)

I bought 20 of these MP38A transistors from a seller on eBay in late February and just received them today.

I originally got them for an Aft PCB I've had assembled since about that time. I plan on plugging one in there and getting that built up, but I was looking for other suggestions for some builds where these would come in handy.

I randomly tested a few of them with a DCA 75 and for the hFE I got: 77, 102, 107, 88, 87, 106. ICleak for those were, respectively, .079, .235, .178, .097, .135, .156

I believe that this tester takes leakage in to consideration when calculating gain.

I'm looking for suggestions for builds. Anything that is bass friendly, or that can easily be modded to be so, would be a plus!


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## fig (May 21, 2021)

Maybe BB -> perf something....really nice numbers there!


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## peccary (May 21, 2021)

fig said:


> Maybe BB -> perf something....really nice numbers there!


I still have my Si FF breadboarded, maybe I'll try plugging some in to that to see how it goes since it's NPN. I'm not sure if I'll have one that's high enough gain for Q2 but it will be fun to experiment with to see how things change. Think I'll play with that this weekend a bit.


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## jjjimi84 (May 21, 2021)

A point to point dirty boost or a tonebender


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## peccary (May 21, 2021)

jjjimi84 said:


> A point to point dirty boost or a tonebender


Oh man.that would be quite the challenge - I've only even breadboarded one thing and that was using a cheat sheet. If I can find something super simple I will have to make it a point to give that a go. As long as I don't compare my end result with yours I'm sure I'll be happy


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## jjjimi84 (May 22, 2021)

peccary said:


> Oh man.that would be quite the challenge - I've only even breadboarded one thing and that was using a cheat sheet. If I can find something super simple I will have to make it a point to give that a go. As long as I don't compare my end result with yours I'm sure I'll be happy



I can take some really detailed pictures and send them to you and help you along. It isnt any harder than breadboarding just more time comsuming.


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## peccary (May 22, 2021)

@jjjimi84 and @thewintersoldier

Thank for the advice and offers of help - I appreciate it.

I am not sure what's possible so if I'm shooting at the moon let me know. Ideally it would be something that I could use on bass, but I do plan on getting myself an inexpensive guitar to play with as well, so I can use it on that, too. I am very much in to breadboarding something and tweaking with it until it's close, but if you could point me in the right direction of where to look I would appreciate that.

I think that in terms of tone I would like something warm that will break up in kind of spitty and mean ways in the top end and where the bottom won't drop out. I am not all that familiar with fuzz pedals other than the WM that I built, which used in a song or two when playing live, but it was way too much for something that could be used as a regular tone-shaper.

I'm not even sure what he's using here, it might not even be fuzz and I'm sure he's got more than just one effect going on, but the tone of the main guitar riff in this song has been haunting my dreams lately. It's warm and has a little bit to it but it comes apart when pushed. I know that a bass will never sound like that, but I'm talking more about replicating what that sound is doing as opposed to trying to recreate the actual tone, if that makes sense.

If the Dan Drive will get me part way down the road that would be great (I have your schematic saved) but if there is a better direction I should be looking I'm all ears.


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## Feral Feline (May 23, 2021)

thewintersoldier said:


> With those numbers almost anything is possible. You could do a fuzz face but that is so blaze'. You want raw or nasty? Maybe a little of both? Something in the tonebender camp. Mk1 is the devil but in a good way, unhinged and raw, spits with attitude. Mk11 is more smooth but the has that bite still. Mk1.5 is a fuzz face without the blown out bottom end. Mk111 is the smoothest and less like mk1 and 2, very different topology but it has a tone control and is more flexible. The buzzaround is a variant of the mk111. It's the mk111 on steroids, more of everything:gain, volume and attitude. The dizzy tone is a tweaked buzzaround and the nastiest of the bunch. If the buzzaround is the devil the dizzy tone is the antichrist, the MF ain't playin around. I'm partial to the MK1 and Dizzy tone. Whatever you build determines what transistors are left and what options you can build from there. If you have questions I would love to help you piss off your neighbors and get the cops called on you!


WOrD!

Dizzy Tone!

Based on youtube clip comparisons I've made, for fuzz the Dizzy Tone is my favourite gottabilldit. 
Yes, "bill'd it" not "build it", 'cause the bill for those little grey elemental temperamental tone-trinket tiddly-winx...

That's what's holding me back from building all these TB & FF variants, the ¢o$t and associated scarcity.
2N3904? — got tons... OC-44? Only in my dreams.


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## fig (May 23, 2021)

https://forum.pedalpcb.com/threads/elka-dizzy-tone.1421/post-9856


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## HamishR (May 25, 2021)

My favourite Ge fuzz is the Marshall Supa Fuzz - made by Sola Sound for Marshall it's a Tonebender with bigger caps, so it's a big fat fuzz with more grunt than a typical TB. It's so simple to build on Vero especially if you have MP38s. You use the lowest gain first (Q1) and the highest gain last (Q3). It's a little tedious but it pays to socket the transistors so that you can keep trying different options. Once you get the right combination you'll know.


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## fig (May 25, 2021)

jjjimi84 said:


> I can take some really detailed pictures and send them to you and help you along. It isnt any harder....



I get text messages like that a lot. Usually I delete them.


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## Betty Wont (May 25, 2021)

I second the Dizzy Tone. I build mine with a clean blend for bass.


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## music6000 (May 25, 2021)

Basically a ToneBender MK III









						Soul Vendor - PedalPCB.com
					

Compare to Fulltone Soul Bender




					www.pedalpcb.com


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## finebyfine (May 25, 2021)

👀 If you want to trade any of those for lower hfe gt308 germaniums lmk


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## peccary (May 25, 2021)

I've spent the last couple of days taking a look at the suggestions here and I really think that I am liking the Dizzy Tone. I have seen a couple of demos that got my attention, mainly this one here using the Jext Dizzy Tone which just sounds unreal to me:






From what I have seen the Jext was based on an original Elka, so I think that is what I am going to go for. I think I will breadboard it first and play with the different transistors. Looks like y'all are going to make me bust out the vero - something I wasn't sure I'd want to do again after discovering this palce!


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## peccary (May 25, 2021)

Just tested each one for gain. Its' about 74 in my house right now and I did my best to not touch them with anything other than the test leads. I love the little grabby ones that come with the DCA 75 - pretty handy.

The 58 and 136 are the oddballs, it seems.

Is the general rule of thumb once I get this built on the BB to go low to high Q1-Q3, mixing and matching till the mojo gods smile down upon you?


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## music6000 (May 25, 2021)

Don't overlook this, Voltage converter so you can Daisy chain it !








						Gnat Fuzz - PedalPCB.com
					

Compare to Burns Buzzaround




					www.pedalpcb.com


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## music6000 (May 25, 2021)

thewintersoldier said:


> I can give you the values to use the gnat board, it's what I built mine on. I have  post on Madbean forums all about it. The dizzy tone is my favorite and I took a deep dive looking up original schematics and info about transistor gains


I saw this post from back when, Did you build end up building it on the Gnat?






						Buzzaround to a DizzyTone
					

I haven’t tried this yet but looking at both layouts I think this is how you convert the Buzzaround board to a DizzyTone  R2 150k R3 680k R8 15k R9 18k C2 25u C3 25u C101 25u Sustain C250k Balance B5k Attack A1m




					forum.pedalpcb.com


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## peccary (May 25, 2021)

music6000 said:


> Don't overlook this, Voltage converter so you can Daisy chain it !
> 
> 
> 
> ...


If I could get a PCB which would allow me to use the same architecture while modifying the component values that would be my ideal. 

I'm still learning most things right now, so I have to ask: what is the purpose of the voltage regulator there?


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## giovanni (May 25, 2021)

looks like the circuit is designed for negative power rail and the regulator produces -9V.


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## music6000 (May 25, 2021)

peccary said:


> If I could get a PCB which would allow me to use the same architecture while modifying the component values that would be my ideal.
> 
> I'm still learning most things right now, so I have to ask: what is the purpose of the voltage regulator there?


So you run it along side & daisy chain it to standard pedals.
The Buzzaround & Dizzy tone are -9v circuits because of PNP Transistors.


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## peccary (May 25, 2021)

music6000 said:


> So you run it along side & daisy chain it to standard pedals
> The Buzzaround & Dizzy tone are -9v circuits.


Sounds like a good thing to know before I go letting all of the magic smoke out, thanks! 

Another good reason to go with a PCB. At least then I know that someone involved in the build knew what they were doing!


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## music6000 (May 25, 2021)

Just confirmed with *thewintersoldier *if your MP38A's are NPN, you can bypass the voltage converter & reverse your Electrolytics & such on the Gnat PCB.


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## peccary (May 25, 2021)

music6000 said:


> Just confirmed with *thewintersoldier *if your MP38A's are NPN, you can bypass the voltage converter & reverse your Electrolytics & such on the Gnat PCB.


I was just looking at the Gnat and saw that the transistors needed there are PNP (mine are NPN), so my *guess* is that I would have to do that, right?


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## music6000 (May 25, 2021)

Yep,we have the technology, we can make it Better,Nasty & Fatter!


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## music6000 (May 26, 2021)

music6000 said:


> Yep,we have the technology, we can make it Better,Nasty & Fatter!


Here it is, the Dizzy Elk for NPN GE transistors, Members can participate if I missed something, B100K can be subbed for Volume :


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## peccary (May 26, 2021)

music6000 said:


> Here it is, the Dizzy Elk for NPN GE transistors, Members can participate if I missed something, B100K can be subbed for Volume :
> 
> View attachment 12161



You are awesome, dude. Hard to think that's all that's needed!

If that is the case I will grab a couple of these boards - that'll help me get things started more quickly.


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## music6000 (May 27, 2021)

Something like this :


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## peccary (May 30, 2021)

music6000 said:


> Here it is, the Dizzy Elk for NPN GE transistors, Members can participate if I missed something, B100K can be subbed for Volume :
> 
> View attachment 12161



I ordered a few boards to play with and they should be here next week. I am planning on making one of them where everything is socketed so I can play with different values and I had a question.

Taking a look at the schematic and your suggestions, everything makes sense to me except as to why C101 would be left in. It looks to me as if it can be omitted, but I wanted to double check here since I am very new to reading schematics.


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## AgAuthority (May 30, 2021)

peccary said:


> I ordered a few boards to play with and they should be here next week. I am planning on making one of them where everything is socketed so I can play with different values and I had a question.
> 
> Taking a look at the schematic and your suggestions, everything makes sense to me except as to why C101 would be left in. It looks to me as if it can be omitted, but I wanted to double check here since I am very new to reading schematics.


Going to want to leave it in, only cap to filter the power supply.

C102 was removed and that cap parallels c101, not shown in original Buzzaround schematic but could be used either way. Somebody smerter than me could explain the benefit but guessing it would be minimal.

Ag


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## peccary (May 30, 2021)

AgAuthority said:


> Going to want to leave it in, only cap to filter the power supply.
> 
> C102 was removed and that cap parallels c101, not shown in original Buzzaround schematic but could be used either way. Somebody smerter than me could explain the benefit but guessing it would be minimal.
> 
> Ag


Thank you. I can sort of follow the logic when things are contained in a single schematic, but when it has multiple in the same schematic (not sure what the correct language is here, but I'm guessing you know what I mean) I really lose track. 

I figured asking rather than just assuming either way was best, and now after your explanation and looking at it again it makes much more sense - thank you!


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## AgAuthority (May 30, 2021)

This thread has sent me down a rabbit hole, got a couple of gnat boards coming and ordered some more mp38a’s........😁

Digging around found a couple threads on freestompboxes on the Buzzaround, then some pics of an original, then some pics of some Pigdog versions. Those make me all gooey eyed, love the hand wired stuff.  You cost me money, and will cost me more before its over.🤣

Ag


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## peccary (May 30, 2021)

AgAuthority said:


> This thread has sent me down a rabbit hole, got a couple of gnat boards coming and ordered some more mp38a’s........😁
> 
> Digging around found a couple threads on freestompboxes on the Buzzaround, then some pics of an original, then some pics of some Pigdog versions. Those make me all gooey eyed, love the hand wired stuff.  You cost me money, and will cost me more before its over.🤣
> 
> Ag


Anything I can do to help!   

I'm still contemplating whether or not I want to try to find one of those massive wedge enclosures to put it in. Might have to wait and see how mean it sounds when I'm done.


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## music6000 (May 31, 2021)

peccary said:


> I ordered a few boards to play with and they should be here next week. I am planning on making one of them where everything is socketed so I can play with different values and I had a question.
> 
> Taking a look at the schematic and your suggestions, everything makes sense to me except as to why C101 would be left in. It looks to me as if it can be omitted, but I wanted to double check here since I am very new to reading schematics.


The Original uses 25uF, I have left 100uf because it is extral Power Filtering & it is more commonly used as Filtering.
You could use lower values but you could also introduce noise!


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## cooder (May 31, 2021)

Something else that sounds great with MP38As is the Skreddy Screwdriver, to bring up another circuit if you have a lone transistor left at the end.


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