@chiily, IMO you are using BC327/337 with very high Hfe's in the PSU, it is not exactly oscillating but it is regulating as expected in a kind of semi-SMPS-mode (I would call it). You could try to use BC's with a lower Hfe or you could try to lower R100, 103, 200 and 203 from 330ohm down to 47ohm. Be sure that C105, 205 are of a high-esr (cheap) type (do not use low-esr capacitors here). Also you could try to add a small (10/20pf or so) capacitor between B and C of Q105, 205.
Thank you for your help...
Okay, I can't remember which hfe bin the PSU BCs came from...I'll try some from the lowest hfe bin, but the hfe of the 337 starts where the 327's hfe finishes
. Is that for all the BCs in the regulator stage, or specific ones to target first?Though Am I better lowering the resistors? Resistors are easier to de-solder
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I have a simple CRCRC with four QSpeed diodes. R is 0.47, C is about 6,800uF each. Really simple...
As I've only built one board I just have one transformer, CRCRC - a mono supply.
I'm not frustrated...The help I'm getting on here is wonderful. I'm sure we'll, together sort out the problems I'm seeing. Then other people can learn from what we have done...
there is always hope
Very funny man.
. I have finished only the PSU stage +/- 18V rocked-solid. Now still waiting for the next bunch of BCs to arrive to measure and complete the next stage itself. In the regulator section i used hFE ~300 BCs.
Very funny man.
None of the BC337s I have go that low..they start at around 500...
My GB BC 337 started from 490 upwards and Bc327 from only 310-360 thus not a single match transistor. I bought some BC 327/337- 25 from tayda electronics but most of them measured up to 300 only so the search continues.From Oz the options are limited in ordering components and so expensive.
Quan.
And we are back to BCXXX40 problem
I have started a new tread maybe worth posting there.
The whole Idea is to swap transistors as needed
http://www.diyaudio.com/forums/swap-meet/226166-paradise-bcxxx-40-a.html
Chiily I have plenty of low 327 (380 Hfe) as posted there and far to many 327 with Hfe abowe 560 my NPN are around 500 (fairchild) and 420 (GB)
Got 2 batches from Fairchild and the ones in goodies bag
Unless we help each others out matching Hfe is a problem
send PM with your addres and I will send you same of what I have if you need it
I am going to order same from diotec from conrads as soon as my bank account recovers from the recent festivity
But once more my R2 boards where built with the realy hi Fairchilds and are fine
I have started a new tread maybe worth posting there.
The whole Idea is to swap transistors as needed
http://www.diyaudio.com/forums/swap-meet/226166-paradise-bcxxx-40-a.html
Chiily I have plenty of low 327 (380 Hfe) as posted there and far to many 327 with Hfe abowe 560 my NPN are around 500 (fairchild) and 420 (GB)
Got 2 batches from Fairchild and the ones in goodies bag
Unless we help each others out matching Hfe is a problem
send PM with your addres and I will send you same of what I have if you need it
I am going to order same from diotec from conrads as soon as my bank account recovers from the recent festivity
But once more my R2 boards where built with the realy hi Fairchilds and are fine
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And we are back to BCXXX40 problem
I have started a new tread maybe worth posting there.
The whole Idea is to swap transistors as needed
http://www.diyaudio.com/forums/swap-meet/226166-paradise-bcxxx-40-a.html
Chiily I have plenty of low 327 (380 Hfe) as posted there and far to many 327 with Hfe abowe 560 my NPN are around 500 (fairchild) and 420 (GB)
Got 2 batches from Fairchild and the ones in goodies bag
Unless we help each others out matching Hfe is a problem
send PM with your addres and I will send you same of what I have if you need it
I am going to order same from diotec from conrads as soon as my bank account recovers from the recent festivity
But once more my R2 boards where built with the realy hi Fairchilds and are fine
Thank you. Pm on your way. BTW i did post on the trade/swap thread but no reply.
quan.
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The Ghz scope is currently in the repair shop EEVblog #405 - Lecroy 9384C Oscilloscope Repair - Part 3 - YouTube
This (and other experiences reported) make me doubt the Hfe hypothesis. If I read these well it may even be that higher Hfe's work better... I have to think about this.
Thank you for your help...
Okay, I can't remember which hfe bin the PSU BCs came from...I'll try some from the lowest hfe bin, but the hfe of the 337 starts where the 327's hfe finishes
Though Am I better lowering the resistors? Resistors are easier to de-solder
The resistors is easiest, just parallel the 330 by a 56ohm value and when it makes no improvements you can easily remove them.
Maybe the next thing to try is adding the ceramic 10/20 (or even up to 100pf) capacitors, this is also easy to implement and remove (if needed).
I finally fired up the Paradise;well regulator sections only as I still need to obtain better matched transistors; and it worked as expected 
I used a transformer with 20V secondaries which gave +- 27.3 vdc at the board and was able to adjust the reg output when things had warmed up.The heatsink settled at 50C after 30/40 mins. Back to matching transistors.
I used a transformer with 20V secondaries which gave +- 27.3 vdc at the board and was able to adjust the reg output when things had warmed up.The heatsink settled at 50C after 30/40 mins. Back to matching transistors.
I finally fired up the Paradise;well regulator sections only as I still need to obtain better matched transistors; and it worked as expected
I used a transformer with 20V secondaries which gave +- 27.3 vdc at the board and was able to adjust the reg output when things had warmed up.The heatsink settled at 50C after 30/40 mins. Back to matching transistors.
Cool, or actually rather warm but not to (e.g. 50degC if fine).
One step beyond: impatient i build up a psu with stock parts of my shelf. Works better like the lipo batteries, no hum, no noise, i´m amazed about the silence.
I think it´s also the result of the shunt regulator design, thank you FdW!
Next step: sending some bucks to italy, buying some cases. I want build it up like my sold pass pearl:
Chris
I think it´s also the result of the shunt regulator design, thank you FdW!
Next step: sending some bucks to italy, buying some cases. I want build it up like my sold pass pearl:
Chris