Interest for Potential GB for Pioneer Super Linear Circuit

[Algar_emi]

2 sets 😉 thanks

 

[EUVL]

Please send HKD440 by Paypal to :
gogowatch_AT_gmail_DOT_com

Please make sure you include your real name and postal address. Else we cannot ship.
Shipment will be registered air. So please make sure someone is there to receive.

Please confirm here after payment is made, so that we know when to check.


Thx,
Patrick

 

[Algar_emi]

8 pcb, and 2 protection. Thanks

 

[EUVL]

Correct.


Patrick

 

[Algar_emi]

Made the payment, but forgot the address. Here it is:

S.Bergeron
348 Huguette
Laval, Quebec, H7P5T8
Canada

Thanks
SB

 

[EUVL]

Noted.

 

[Algar_emi]

Thanks
SB

 

[EUVL]

Tracking number (HK Post Office) :
RE032526019HK


Patrick

 

[Algar_emi]

Started the Pioneer project, beginning with the JFET & Transistor matching. Here my results for the 2SK4883 & 2SA1959 HFE matched pairs, not so difficult to get with a quantity of 25of each, and the JFET 2SK209GR IDSS. All my JFET fit within 5 groups of IDSS. I'll run on close IDSS group through my curve tracer to see their transconductance curves, and I'll choose the closest pairs.

 

[EUVL]

Matching the 2SC3324BL / 2SA1312BL is more challenging.

🙂


Patrick

PS Better to post building information at the original thread on the headphone section.

 

[Algar_emi]

I'll use your very nice 'Matched Page' as an example, and I'll place the small parts into the same box. Now time to measure 200 little parts 😉
SB

 

[Algar_emi]

Houston we have a problem! Take a look at my HFE measurement results. Most of the 2SA1312-BL (PNP) are around 481 to 520 HFE, but the 2SC3324-BL (NPN) are rather from 411 to 440 HFE, so no easy HFE matching between NPN and PNP.
Any recommendation, and or comments? Do I have to reorder the transistors and hope for better overlap?
Thanks
SB

 

[anatech]

Hi SB,
Well, all these beta numbers are fantasy. Beta changes strongly with temperature, and unless you can keep the transistors at the same specific temperature, beta readings are only extremely approximate. I'll believe the trend, but not the individual readings.

I don't know what to tell you. Without a temperature controlled jig, you can't really do what you are trying to do. This is especially true if you don't do all the measurements at the same sitting away from sunny windows (basement would be best in a dark corner), and you can't breathe on them. It takes extreme care to get closer approximate numbers.

-Chris

 

[EUVL]

Answered here, post #130 :
The Pioneer Super Linear Circuit


Patrick

 

[Algar_emi]

They were tested with a SOT23 smd jig, that yes close over the parts, into an stable temperature room, and yes, in the basement, away from the sun (the man's cave, as called by my wife), but I'll have a look at Patrick's suggestion. Thanks anyway for the comment.

 

[emyeuoi]

Ciao Patrick,

Arghh... As usual I am late 🙁 Just discovered this nice project

Any chance you have spare pcbs?

Thanks and Regard,
Enrico

 

[EUVL]

Check your PM.


Patrick

 

[arnd13]

Hello Patrick,

ist it possible to get 2 pcbs (only the pcbs of the amplifier)?

Thanks and Greetings from Germany

Arnd

 

[arnd13]

I forgot, of course the pcbs for the ccs too 🙂

 

[EUVL]

You may wish start a (new) GB-2 thread and wait till we have minimum 10 subscribers.
We'll only offer the PCB set, as in GB-1.


Patrick