Paradise Builders

[Joachim Gerhard]

It eats batteries for breakfast. I put wires to the outside and supply it with my lab PSU.

[miepa]

guys,
i wasnt part of the GB, so, low current leds are recommanded, right?
thank you.

[Joachim Gerhard]

yes, 2mA types.

[difool]

Dubai, can you read german? Nothing against ATLAS,
I ordered according to HB:
Paradise – Transistor matching | Holger Barske

Originally Posted by dubai2000

I am new to transistor matching so the question might be silly, but would a device such as the following be useful?

Found at Reichelt: ATLAS DCA55

Your feedback will be appreciated - thx.

dubai2000

[FdW]

Originally Posted by FdW

I will, tonight, have a look at them. At first glance it seems the V(be Q102) is a bit low, and that this is debit of the current unbalance.

Yesterday I did not manage to do this, I will try to do it this evening

[dubai2000]

Thanks for all the feedback - including for the link to Holger's page.

dubai2000

[Joachim Gerhard]

The Hfe tester that Holger found works well but it does nave have the much higher functionality of the Atlas. If you do only want to select BJTs for the Paradise it is sufficient.

[beetle]

Originally Posted by FdW

Yesterday I did not manage to do this, I will try to do it this evening

No problems. Take your time.

[sq225917]

Joachim, I'm worried about transistor matching how close do they actually have to be?

Is it more important to have a good balance between 327 and 337 or more important to have them matched within each quad, ie 4 327 with the same value as each other?

I can get good quads, ie 4 x 327 with identical values, or I can get a good balance with a looser match yielding a combined HFe that matches between 327 and 337. But I can't get closely matched for both...


Failing that does anyone have 8 337 with an HFe of 400?

I will put my list up later today

[Benedetto]

After matching approx. 800 each still trying.
I will order again 300 each from a reliable source...