Need help quick please! P101 bias related

ShinOBIWAN · 25th April 2005, 10:54 AM

Hi all!

I'm just about to test my P101 that I've finished constructing.

Problem us I'm unsure as to whether or I have the bias set to min or max

pps:
Rod says to set resistance to minimum on the 20k pot, I have installed it in the same orientation as shown below:

Do I turn fully clockwise or anticlockwise as you look at the board in the picture above for min resistance?

Help please, and thanks.

pinkmouse · 25th April 2005, 11:09 AM

Morning!

Use your meter set on ohms to find out which pin is the wiper on the preset, (usually the centre), then with your probes across the two other pins alter the setting until you get minimum resistance.

ShinOBIWAN · 25th April 2005, 11:12 AM

Also where does the '-' from the speaker go to?

Is it P-GND?

richie00boy · 25th April 2005, 11:14 AM

The speaker ground returns to the star point at your PSU caps.

pinkmouse · 25th April 2005, 11:14 AM

Star ground.

pinkmouse · 25th April 2005, 11:14 AM

Snap!

ShinOBIWAN · 25th April 2005, 11:14 AM

Quote:

Originally posted by pinkmouse
Morning!

Use your meter set on ohms to find out which pin is the wiper on the preset, (usually the centre), then with your probes across the two other pins alter the setting until you get minimum resistance.

Morning to you good sir!

Thanks I'll try that.

ShinOBIWAN · 25th April 2005, 11:18 AM

Quote:

Originally posted by richie00boy
The speaker ground returns to the star point at your PSU caps.

Cheers PM and Rich, what a helpful bunch.

Only problem is I don't have a starground on my PSU, here take a look:

Hmm what do I do?

pinkmouse · 25th April 2005, 11:42 AM

One of the 0V tags should do.

richie00boy · 25th April 2005, 12:03 PM

Quote:

Originally posted by pinkmouse
One of the 0V tags should do.

Choose the one located most central on the trace. Look on the copper side.

25th April 2005, 10:54 AM	#1
ShinOBIWAN diyAudio Member Join Date: Feb 2004 Location: UK	Need help quick please! P101 bias related Hi all! I'm just about to test my P101 that I've finished constructing. Problem us I'm unsure as to whether or I have the bias set to min or max pps: Rod says to set resistance to minimum on the 20k pot, I have installed it in the same orientation as shown below: Do I turn fully clockwise or anticlockwise as you look at the board in the picture above for min resistance? Help please, and thanks.

25th April 2005, 11:09 AM	#2
pinkmouse diyAudio Moderator Join Date: Apr 2002 Location: Chatham, England	Morning! Use your meter set on ohms to find out which pin is the wiper on the preset, (usually the centre), then with your probes across the two other pins alter the setting until you get minimum resistance. __________________ Al I conceive of nothing, in religion, science or philosophy, that is more than the proper thing to wear, for a while. Charles Fort

25th April 2005, 11:14 AM	#4
richie00boy Did it Himself diyAudio Member Join Date: Nov 2003 Location: Gloucestershire, England, UK	The speaker ground returns to the star point at your PSU caps. __________________ www.readresearch.co.uk my website for UK diy audio people - designs, PCBs, kits and more

25th April 2005, 11:14 AM	#5
pinkmouse diyAudio Moderator Join Date: Apr 2002 Location: Chatham, England	Star ground. __________________ Al I conceive of nothing, in religion, science or philosophy, that is more than the proper thing to wear, for a while. Charles Fort

25th April 2005, 11:14 AM	#6
pinkmouse diyAudio Moderator Join Date: Apr 2002 Location: Chatham, England	Snap! __________________ Al I conceive of nothing, in religion, science or philosophy, that is more than the proper thing to wear, for a while. Charles Fort


	Please consider donating to help us continue to serve you. Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving

25th April 2005, 11:12 AM	#3
ShinOBIWAN diyAudio Member Join Date: Feb 2004 Location: UK	Also where does the '-' from the speaker go to? Is it P-GND?

25th April 2005, 11:42 AM	#9
pinkmouse diyAudio Moderator Join Date: Apr 2002 Location: Chatham, England	One of the 0V tags should do. __________________ Al I conceive of nothing, in religion, science or philosophy, that is more than the proper thing to wear, for a while. Charles Fort

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
quick question on fixed bias	sorenj07	Tubes / Valves	3	6th August 2007 02:26 PM
esp p101	djronbxs	Solid State	2	6th January 2007 01:02 AM
Setting the bias on an ESP P101	still4given	Solid State	17	31st January 2005 05:36 PM
p3a bias trouble, quick question :)	Mattyo5	Solid State	13	13th May 2004 08:03 PM
quick bias tolerance question...across source resistors	Mattyo5	Solid State	6	12th October 2003 11:09 AM

New To Site?	Need Help?
Register to Participate Search Privacy Statement Contact Us	Frequently Asked Questions Did you forget your password? Mark Forums Read