Rangemaster layout

[kurtlives]

http://aronnelson.com/gallery/v/album26/Rangemaster.gif.html

Is this a good layout? Like does it look right?

What layouts have you guys used?

[jrem]

I just use perf and solder the leads together, the circuit is so simple, and so few components.

It's picking the transistor that makes the difference.

[kurtlives]

Ya I know I am using a 3PDT to switchbetween a OC44 and a OC71.

HAs anyone heard of a hard/spft gain mod? I think it has something to do with the 47mF cap.

[kurtlives]

Can a OC44 be used for both positive and negative ground?

[kurtlives]

EDIT: Never mind....

[hairyandy]

Can a OC44 be used for both positive and negative ground?

Yes, as long as the rest of the circuit is correct in respect to polarity.  My layout that you referenced above works, I've built a ton of Rangemasters using that layout.

ANdy

[kurtlives]

Ahhh thank you Andy. Nice layout btw.

So if OC44s (I am also using a OC71 btw) can be used for both negative and positive ground why are most positive fround.

Are OC44s better for positive ground?

[hairyandy]

Ahhh thank you Andy. Nice layout btw.

So if OC44s (I am also using a OC71 btw) can be used for both negative and positive ground why are most positive fround.

Are OC44s better for positive ground?

Yeah, OC44s and OC71s are both PNP devices that are designed to be used with positive ground.  You can use them with negative ground if the circuit is designed for it, although it's not necessarily recommended or optimum with many circuits.  The RM circuit is so simple that I haven't had any issues with oscillation or motorboating with my layout.  This may not be the case with other layouts or other circuits when running PNP negative ground and may even vary from one device to the next.  YMMV.

I always say just try it.  If it sucks or sounds bad try something else.  I like the negative ground because I don't have to use the same power supply as my other effects on my board.

Andy

[kurtlives]

Alright thanks.

Now I have to rewire my adapter

[hellwood]

Alright thanks.
Now I have to rewire my adapter

adapter? a battery will last forever in that thing and it will probably sound better!

[newfish]

Sooo.

Spent a while on Sunday tracing through drawing a schematic for this, based on the vero layout linked above - got it right on the second attempt.

Slowly teaching myself breadboarding (definitely hang in there - makes it so much easier to swap components around), so built another Rangemaster directly from the schematic, and after about 4 attempts, *finally* got my head around it.

Also - learned a bit about Biasing - first RM I made has nearly 8v going through, this one has 6 and a bit - and is much warmer.

Final modification was to change the Cap. on the output to a full 1 microfarad.

Decided on this value to try to rid myself of the 'DC' noise coming through - although it shaves a bit of the top-end off (which I was never keen on anyway...) - and thanks to the circuit being on a Breadboard, I could take my time experimenting with different values without any risk of damaging my OC44.

Also, was careful to remove the Battery before changing *any* components - just to be on the safe side.  When your Transistors are celebrating their 30th Birthday this year, there can't be too many of them left out there...

[hellwood]

Final modification was to change the Cap. on the output to a full 1 microfarad.
- although it shaves a bit of the top-end off (which I was never keen on anyway...)

thats what i thought until i used it with the marshall cranked on 10 outside on a big stage.