Plethora of Pinjatas / SET P amp(s)

[Russellc]

With temporary power supply, dual mono transformers on way. This will do to fire it up!

 

[Zen Mod]

split washers on bridges?

asking, just in case....

 

[Russellc]

Not yet, just figuring out where to stick things. Yes, I bought one of those big plastic boxes of various sizes of split washers!

 

[Russellc]

Only thing left is a CL 60 to ground the power supply to chassis. No CL60! I do have CL30, and I have an extra original power supply F5m kit, which has a couple smaller thermosistors and a larger green one.

Would either of those work in this chassis ground position? I'm figuring bigger, not smaller would be better. Hate to hold up fire up over a CL60 order!

Thanks, I need to order another pile of CL 60 anyway ...

Russellc

 

[Zen Mod]

one CL30 should work proper, only if you have enough to put 2 in series, even better

 

[Russellc]

I have exactly two! Thanks, hopefully fire up this evening after work!

Russellc

 

[rhthatcher]

You should love this amp! It's been running 500Hz and up in my active horn system with XA252 SET on the mid-bass duties. Both are simply incredible.

 

[Zen Mod]

PoP is XA252 for Sissies

 

[Russellc]

You should love this amp! It's been running 500Hz and up in my active horn system with XA252 SET on the mid-bass duties. Both are simply incredible.

Have you also built F8? Thats another one Im interested in. Turning all parts boxes upside down searching for those two CL-30, which are hiding somewhere giggling at me. Before F8 I will build new XA 252...

Russellc

 

[Russellc]

Never found the CL30, but found some
CL 60 pieces! Now then!

Russellc

 

[Russellc]

4 of them.

 

[Zen Mod]

 

[Russellc]

All ready to fire up first channel. For the DMM on the bias, should I hook up the dmm as in figure #1, or since this is "mini" XA 252,
I assume that figure #2 is good too? That's how I did it on XA 252.....Pic in a quick..

Russellc

 

[Russellc]

One of your pics in post #2 shows your hookup using method #2. Guess I will do it as such, and check other way too, looks like same setup as XA252.

Russellc

 

[Zen Mod]

clips across any 0R22 resistor, resulting that clips being across 0R11 resistance, so 198mV being 1A8 Iq

 

[Russellc]

1st channel now at 120 volts via variac. Bias is .95mV, about half, offsett 16 mV. See if sinks warm before increasing bias. Oh, greenie led came on of course

Few minutes later, sinks beginning to slightly warm, few more up to 120 mVish for more warming

Russellc

 

[ItsAllInMyHead]

^ In my head I always hear Howard Cosell as I read your play-by-play accounts.

 

[Russellc]

Bias and offset are dead steady as rock, 120 mV bringing slightly more heat. Few more minutes and will go 150 mV or so, then close JP, lower offset, open JP and go for final bias, then to channel 2.

 

[Russellc]

^ In my head I always hear Howard Cosell as I read your play-by-play accounts.

How about Walter Cronkite? "And that's the way is is, 150 mV"

 

[Zen Mod]

be back when you hear it sing