My Take on X-BOSOZ

[eapavant]

Anyone get the PE trans. working yet? I am about to fire mine up with 2 33v zeners on the + and one 15v zener on the - . I am not sure if I need to change the values of R5 and R6? I guess it might be tuned for maximum smoke. Fingers crossed.

[AR2]

What resistors are responsible for gain? Would that be R18 and R19? What are side effect of changing these since my understanding is that they regulate amount of feedback? I understand that on original Bosoz R15 regulates gain, but on X ccs Bosoz there is no such a resistor. Is there any problem lowering gain to very low level?

[jh6you]

Originally posted by AR2

Would that be R18 and R19?

I think another way is possible,
by adding source resistors just under the Q4 and 5.
Details could be adviced by X-BOSOZ experts . . .

Regards
jh

[chipco3434]

Anyone get the PE trans. working yet? I am about to fire mine up with 2 33v zeners on the + and one 15v zener on the - . I am not sure if I need to change the values of R5 and R6? I guess it might be tuned for maximum smoke. Fingers crossed.

No, but I'm watching you carefully.. also with fingers crossed. Are you on the 14-0-14 taps for the - ?

[eapavant]

Ok, I got both + sides working with 2, 33v zeners. I changed r5 to a 1/2w and added a seccond 221 Ohm 1/2w. I changed r5 because I kept smoking it, now it seems to work. 70.04v on both boards. I have not got on the - side because I just got a box with 40 9610's from ups I was thinking of using 16v from the trans. not the 14. I will report back when I find out.

[chipco3434]

Thanks for the info...

As it was once explained to me, learning is discovery~

but I am ALL DISCOVERED OUT!

see my posts on smokey output boards:

Oops

and funky voltage on a no brainer PS:

Huh?

I just can't take another challenge. Thanks for posting!

[eapavant]

I know what you mean. I have to learn all this stuff as I go to.

[SteveA]

Originally posted by chipco3434


No, but I'm watching you carefully.. also with fingers crossed. Are you on the 14-0-14 taps for the - ?

I'm using Kari's design which runs on+60/-12V and have gotten the correct voltages from this transformer. If this is the same transformer I have it has
1) 55-0-55
2) 16.2-0-16-2 and
3) 14-14 (no centertap)

I used 1) for the +60 and 2) for the -12 and got +59.7 and -11.5.

SteveA

PS, haven't fired it up yet

[eapavant]

I am using the 55 and 16. Two 33v zeners on the + and one 24v zener one the -. I get 70.03 and -20.2, I might be off by a few tenths as I do not have my notes with me. That is as far as I have gotten so far. I have to many projects going

[chipco3434]

Ok, I got both + sides working with 2, 33v zeners. I changed r5 to a 1/2w and added a seccond 221 Ohm 1/2w. I changed r5 because I kept smoking it, now it seems to work. 70.04v on both boards. I have not got on the - side because I just got a box with 40 9610's from ups I was thinking of using 16v from the trans. not the 14. I will report back when I find out.

I understand the switch to 1/2 watt in positions r5 (and R6?) but don't understand "and added a second 221 Ohm 1/2w".

For use with the PE tranny, I am placing (2) 33V 1w zeners in ZD+1 and ZD+2 with jumps at ZD+3 and ZD+4. On the - side, one 15V 1w at ZD-1 and jumps on ZD-2, ZD-3, and ZD-4. If this is not correct, would somebody let me know before the smoke gets out.

Thanks!