Hi There
I need some help.
I´m starting to build some pedals... by the way I f**** love it ;D ... for last 5 days start build 4 circuits... but for a noob like me the questions are a lot! Hehehe
Ok, so I have my pcbs, buy the way i´m etching my pcb´s with magazine paper and having nice results, waiting for some IC´s that i bought from ebay and yesterday started on the rangemaster.
On the rangemaster we have the OC44 but here in Lisbon I cant find it, so in that quest I found a shop that sold me an AF200, an transistor that is an replacement for the OC44 (according to a old book that the guy had)
But this transistor as 4 pin... I know that the 4pin is the case ground but...
So, my questions is:
Can I use this AF200? anyone try it? Do I need to change any of the resistor for bias?
What about the 4pin? Cut it off? Solder it?
Thanks
Is the fourth pin attached to the transistor casing in any way? It might be a grounding pin for the case.
hi madben
No. The 4 pin is not connect to the case. the man from the shop told it was the grounding pin for the case.
here is the tran:
(http://www.radiomuseum.org/images/tubephoto_klein/af200_siemens.jpg)
i was reading on the web people using the ac128 or the ac188 with nice results but haven't found it either!
thanx
Oh, sorry, I did not read your first post thoroughly. You already said that!
I would not clip it out. Use a transistor socket, then put a wire on that grounding pi and attach it any grounding point on the PCB. That way if you ever decide to swap out the transistor in the future, you have not altered your AF200 irreparably.
I cannot speak as to how well it works for the Rangemaster since I've never come across this little guy. But, with a socket you'll find out easily enough.
Ok md
But This circuit is positive ground... Can i attach it to ground?
Quote from: gtangas on December 19, 2012, 05:33:39 PM
Ok md
But This circuit is positive ground... Can i attach it to ground?
Yes you can but watch out with the pinout of the af200 . I think it s BEC (not sure) , and also sometimes it s hard to know wich pin is the shield pin . I suggest you test it without using the shield pin first .