that's your problem ...... and mine and any other Greedy Boy's problem
Pap is turning da pots with mind power
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Use the force Luke
Shouldn't that be, use the Zen.
But then again, if were talking Zen, then it would be a matter of, it doesn't matter.
As all will be balanced in the universe.
AH HA.
Thats what were doing wrong with all our amps.
It is not the amps adjustment that we should be looking at.
We should in reality be looking at adjusting the universe around the amplifier.
Just like light speed travel and the infinite improbability drive....
But then again, if were talking Zen, then it would be a matter of, it doesn't matter.
As all will be balanced in the universe.
AH HA.

Thats what were doing wrong with all our amps.
It is not the amps adjustment that we should be looking at.
We should in reality be looking at adjusting the universe around the amplifier.
Just like light speed travel and the infinite improbability drive....
I tend to adjust my speakers ...... then build smaller Papamps
well , to at least babelfish them

well , to at least babelfish them

which are the fairchild parts used in the amp?
http://www.zenmod.in.rs/wp-content/uploads/2016/04/MB-from-left.jpg
http://www.zenmod.in.rs/wp-content/uploads/2016/04/MB-from-left.jpg
Attachments
which are the fairchild parts used in the amp?
http://www.zenmod.in.rs/wp-content/uploads/2016/04/MB-from-left.jpg
Um, Would it matter ?
Making your own ?
Anyway, i can see in that pic several fairchilds. Just look for the ye old style 'F' on the transistors.
that's question for Old'n'Cranky
Er, ok ?
Why ?
Or do we want better pics ?
Edit.
See if this helps you 🙂
Look at the transistors with the heatsinks.
Note the 'F'..
Attachments
Last edited:
Um, Would it matter ?
Making your own ?
Anyway, i can see in that pic several fairchilds. Just look for the ye old style 'F' on the transistors.
Er, ok ?
Why ?
Or do we want better pics ?
Edit.
See if this helps you 🙂
Look at the transistors with the heatsinks.
Note the 'F'..
I think they are mosfets than transistors but couldnt find any fairchild part with that part number..
papa once said that using transistors to drive mosfet never pleased him so im thinking that they are mosfets but if anybody knows what are those parts then i would like to try driving the output stage with them..
Im trying to figure out which is the number.FQP and FQN
beat me which numbers ......
Hi
I have XA30.5. I have measured voltage on A bias and B bias points and it is ~160mA.
Also I have measured temperature of the heatsinks "by hand", they are hot but nothing special, I can keep my hand as much I want.
According info on internet Iq of the XA30.5 is 1.3A and for X150.5 it is 0.7A.(according Zen Mod voltage on A bias and B bias points and should be 110-140mA for the X150).
So I'm a little bit confused what voltage I should have on bias points of my XA?? Does it should be double than X150.5???
thanks
I have XA30.5. I have measured voltage on A bias and B bias points and it is ~160mA.
Also I have measured temperature of the heatsinks "by hand", they are hot but nothing special, I can keep my hand as much I want.
According info on internet Iq of the XA30.5 is 1.3A and for X150.5 it is 0.7A.(according Zen Mod voltage on A bias and B bias points and should be 110-140mA for the X150).
So I'm a little bit confused what voltage I should have on bias points of my XA?? Does it should be double than X150.5???
thanks
Last edited:
XA30.5 - ref. voltage at bias probe headers is 150mV , according to Papa papers
however , palm rule procedure is , as I wrote , referent
except if you're keeping your amps on snow and ice ......
however , palm rule procedure is , as I wrote , referent
except if you're keeping your amps on snow and ice ......

most probably FQP3P20 and FQP3N30
They are. You can still get them at Digikey.
We have since switched to the Toshiba 2SJ313 and 2SK2013.
😎
XA30.5 - ref. voltage at bias probe headers is 150mV , according to Papa papers.
I seem to recall that figure as the starting point. Warmed up and with the
lid on, we are in the 200 mV region (it drifts up with temperature). This gives
a DC bias of about 2A/ ch, and with a little help from the square law, the
outputs see shutdown just abut 60W peak (30 rms).
It's important to note the actual bias figures after an hour or so with the lid on.
😎
Thanks Mr Pass 🙂
Yes, I have measured voltage on the bias points after an hour or more with lid at place.
Does the same values are applicable to INT-30??
Darius
Yes, I have measured voltage on the bias points after an hour or more with lid at place.
Does the same values are applicable to INT-30??
Darius
Thanks Mr Pass 🙂
Yes, I have measured voltage on the bias points after an hour or more with lid at place.
Does the same values are applicable to INT-30??
Darius
Probably not. I don't have those values, so you need to check with the
factory. All else fails, use "ZM's criteria", heat sink tops at 50 deg C after a
couple hours.
😎
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