F5 Turbo Builders Thread - Page 170 - diyAudio
Go Back   Home > Forums > Amplifiers > Pass Labs

Pass Labs This forum is dedicated to Pass Labs discussion.

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
Reply
 
Thread Tools Search this Thread
Old 24th March 2013, 05:29 PM   #1691
diyAudio Member
 
Join Date: May 2012
Location: Northamptonshire, UK
Hi All

Have made the correction now to Jfet wiring. Pictures attached. Also inc a picture of the underside of the PSU. Have used 2.0mm silver-plated copper wire. The blue and black flex wires hanging of of the audio boards are for test purposes only.
Attached Images
File Type: jpg _DSC0279.jpg (729.1 KB, 447 views)
File Type: jpg P1070225.jpg (411.2 KB, 351 views)
File Type: jpg _DSC0280.jpg (984.3 KB, 357 views)
  Reply With Quote
Old 26th March 2013, 09:47 PM   #1692
Rixsta is offline Rixsta  United Kingdom
diyAudio Member
 
Join Date: Feb 2004
Location: Barrow-In-Furness, Cumbria
Send a message via Skype™ to Rixsta
Lovely Amp there!

just wondering, would this transformer do for F5T ?

Toroid transformer 600VA, 230V/2x24V/2x12,5A, dia.153x68mm, wire 150mm, 5,0kg
Toroidal transformer TST 600/224 | GES-ELECTRONICS

I ask as it looks rather small, also it says how many amps the 2x12v is but not the 2x24
__________________
www.Rixsta.co.uk Free music recorded by me/DIY pics Currently Selling, amps=Zen V4, Zen-lightenment‎, Jean Hiraga 20w, F5, F5T
  Reply With Quote
Old 26th March 2013, 09:54 PM   #1693
Rixsta is offline Rixsta  United Kingdom
diyAudio Member
 
Join Date: Feb 2004
Location: Barrow-In-Furness, Cumbria
Send a message via Skype™ to Rixsta
I think id probably go with this one tho
600W Toroid transformer Input:0-115-230V Output:24V-0-24V 12V-0-12V | eBay

Hows that look for F5T ? and i think on the 12v winding i could probably somehow power the B1 Buffer. 2 birds with one stone! poor birds
__________________
www.Rixsta.co.uk Free music recorded by me/DIY pics Currently Selling, amps=Zen V4, Zen-lightenment‎, Jean Hiraga 20w, F5, F5T
  Reply With Quote
Old 26th March 2013, 09:58 PM   #1694
nrg2009 is offline nrg2009  United States
diyAudio Member
 
Join Date: Apr 2009
Location: Detroit, born and raised in the netherlands.
True, a third bird would be harmed if you used the 12V for a speaker protection board.
  Reply With Quote
Old 26th March 2013, 10:42 PM   #1695
lgreen is offline lgreen  United States
diyAudio Member
 
lgreen's Avatar
 
Join Date: May 2003
Location: San Diego, USA
Quote:
Originally Posted by AndrewT View Post
If you adopt the dual purpose soft start and slow charge by inserting a resistance in the primary then you must use a long time delay.

If you adopt that long time delay then the consequence is resistor overheating.
But the basic problem is that a primary resistance is not effective in limiting the secondary current.

If one adopts a combination of high resistance Power NTCs to avoid the resistor overheat risk, then you will find that the secondary current limiting is even less effective, due to the large reduction in resistance of the now hotter NTCs.

It seems that my message is not getting through.
Would you all start thinking and if necessary measure the effectiveness of your slow charge proposals and report here to prove me wrong. I am sure there are many who would love that outcome and an apology from me for misleading the whole community.
There's the challenge. Prove that added resistance in the Primary is effective in limiting the charging current of the capacitors in the secondary circuit.
I have a lot of amps over here and have used soft starts consisting of NTCs inline with the primary then switched out after a delay. A couple CL-60's, 70's or 80's (10-46 ohms each).

When the relay switches out the NTCs to connect the primary directly to the AC line you can hear the inrush "booooing" into your amp. Increasing the primary resistance and increasing the delay don't do very much. Its hard to measure with a DMM because the DMM cannot lock on so good so a little tricky to see what is going on.

I can confirm what Andrew is saying, the technique of putting resistance before the primary does not work so great. Maybe it would if you really had a large amount of resistance but I have never tried anything much over 100 ohms.

That said, I've not blown any fuses with my amps so while its not perfect it seems to be doing ok.
__________________
Retired from DIY (2010) but still lurking now and again. My DIY audio projects- PartTimeProjects.com.
  Reply With Quote
Old 27th March 2013, 07:30 AM   #1696
oiphy is offline oiphy  Norway
diy newbie
diyAudio Member
 
oiphy's Avatar
 
Join Date: Sep 2011
Location: norway
Quote:
Originally Posted by Rixsta View Post
I think id probably go with this one tho
600W Toroid transformer Input:0-115-230V Output:24V-0-24V 12V-0-12V | eBay

Hows that look for F5T ? and i think on the 12v winding i could probably somehow power the B1 Buffer. 2 birds with one stone! poor birds
Transfer Multisort Elektronik ? Online-katalog | Mer šn 100 000 produkter som erbjuds


bought 4 pcs from tme. quick and easy.
__________________
" If you're going throu hell, keep going"
  Reply With Quote
Old 28th March 2013, 08:22 AM   #1697
AndrewT is offline AndrewT  Scotland
diyAudio Member
 
Join Date: Jul 2004
Location: Scottish Borders
Quote:
Originally Posted by lgreen View Post
............... but I have never tried anything much over 100 ohms.

That said, I've not blown any fuses with my amps so while its not perfect it seems to be doing ok.
I have used 140r in a couple of soft starts with smaller toroids.
__________________
regards Andrew T.
  Reply With Quote
Old 28th March 2013, 11:27 PM   #1698
diyAudio Member
 
Join Date: May 2012
Location: Northamptonshire, UK
Default Zen Mod, F5 testing process

Hello

About to turn on the amp for the first time. I have already tested the PSU which gives me 35v.
Can anyone please explain to me in layman terms what 'IQ' means in this context? Is this the low voltage across R7 and R8?

I understand the principles of 'offset' between PSU and speaker out.
  Reply With Quote
Old 28th March 2013, 11:36 PM   #1699
Zen Mod is offline Zen Mod  Serbia
diyAudio Member
 
Zen Mod's Avatar
 
Join Date: Jan 2003
Location: ancient Batsch , behind Iron Curtain
Iq means quiescent current ;

don't rush ; re-read that little setting tutorial few times

it will settle eventually , and you'll know what you're doing
__________________
my Papa is smarter than your Nelson !
clean thread; Cook Book;PSM LS Cook Book;Baby DiyA ;Mighty ZM's Bloggg;Papatreasure;Papa...© by Mighty ZM
  Reply With Quote
Old 30th March 2013, 12:37 PM   #1700
Rixsta is offline Rixsta  United Kingdom
diyAudio Member
 
Join Date: Feb 2004
Location: Barrow-In-Furness, Cumbria
Send a message via Skype™ to Rixsta
Default power supply

Need a little input here, do you think id be crazy if i had one of these per channel for the power supply?

6*10000UF/50V The protection of high quality Power supply board with speaker AC | eBay
__________________
www.Rixsta.co.uk Free music recorded by me/DIY pics Currently Selling, amps=Zen V4, Zen-lightenment‎, Jean Hiraga 20w, F5, F5T
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
F5 Turbo Circuit Boards chchyong89 Pass Labs 2342 9th July 2014 12:15 AM
F5 Turbo is posted Nelson Pass Pass Labs 635 6th April 2014 10:51 AM
B1 builders thread Bas Horneman Pass Labs 694 25th February 2014 06:29 PM
F5 turbo problems Rob Dingen Pass Labs 17 11th January 2013 08:38 PM
F5 Turbo ............. if only !!!!!! a.wayne Pass Labs 23 21st January 2012 02:24 AM


New To Site? Need Help?

All times are GMT. The time now is 05:52 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright ©1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2