F5T Premium kit GB - Page 33 - diyAudio
Go Back   Home > Forums > Commercial Sector > Group Buys

Group Buys Members group buys

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 18th December 2012, 09:39 PM   #321
sts9fan is offline sts9fan  United States
diyAudio Member
 
Join Date: Apr 2006
Location: MA
dK 845 - V3 (2) , PSU (2) - Yes
RusselC - V2, PSU - Yes
Dane - V2, PSU - Yes
mkoerner - V2 (2), V3 (1)
mordikai - V2 (2), PSU - yes
mordikai - V3 (2), PSU - yes
sts9fan - V2, PSU - yes
Naturlyd - V2 (2), V3 (2), PSU - yes
Wijgers - V2, PSU - no
SRMcGee - V3, PSU - yes
skunark - V3, PSU - yes
Tytte71 - V3, PSU - yes
Bugzbunny - V3 (2), PSU - Yes
Kvorning- V3(2), PSU -Yes
wjh - V2, PSU - yes
backefel - V2, PSU -yes
Lo_Tse - V3, PSU - no
RKH - V3, PSU - no
fudce - V3, PSU - yes
PKI - V2, PSU - no
mortron - V1/V2 Std, PSU - yes

I had to make a change. I also fixed it in the spreadsheet.
  Reply With Quote
Old 18th December 2012, 11:33 PM   #322
Lo_Tse is offline Lo_Tse  Canada
diyAudio Member
 
Join Date: Dec 2006
Quote:
Originally Posted by theguy View Post
Buzzforb,

I see you've consolidated the V1/V2 columns: was going to ask about that.

I've specified a zero tax and shipping rate in that sheet for now; will add shipping column to orders sheet.

One other thing I noticed is that lo_tse's custom order comments and price has been over-written with the calculated order price; don't know whether you or lo_tse changed this.

Here's what he/she had originally:
- $125 (kit price) + $64 (2 sets of FETs) + $24 (16 diodies) =$213.00. I added extra components (see column L). My total price will be $213 + $44 = $257.00. Please double check my calculation.
- would like to get 2 x CL30, 2 xCL60 thermistors, 4 extra diodes, and one more set of FETs ($6.0 + $6.0 + $32.00 = $44 extra)

theguy,

Thank you very much for keeping track of things and managing the spreadsheet. I have updated my order in the sheet (again!) and I will remind Buzzforb about my extra order when he collects funds.

Regards,
  Reply With Quote
Old 18th December 2012, 11:58 PM   #323
Lo_Tse is offline Lo_Tse  Canada
diyAudio Member
 
Join Date: Dec 2006
Quote:
Originally Posted by theguy View Post
OK, got it: wasn't understanding how the factor applied.

One question:
- if I do that multiplication on 25V, I get 32V, which is the rail voltage specified in the manual for V1/V2 main board schematics: so far, so good
- however, the manual refers to a rail voltage of 48V for beefed up V2 PSU, but this may just be example calculation: not really following how this PSU section fits in
Since the PSU for the amp is a capacitor filtered one, the output voltage will be secondary voltage (an rms value) x 1.414. E.g. 25 secondary x 1.414 = 35.35 V => this is the output voltage. However, one also has to consider voltage drop over the diode/rectifer bridge (~0.6/0.7 v per junction). And do not forget that we are using a CRC filter, there will be voltage drop across the resistor. Depending on the current bias set for the output FET's, the drop will be total current draw multiply by the reisitor value. E.g. if the total current draw is 4 amps, the drop will be 4 x 0.1 ohm = 0.4 V. Lastly, when the load is heavy and draw a lot of current , the voltage will sag a bit too.

Overall, prepare to lose 2-3 volts of the output voltage. Anyway, whether you are using 31V or 30.5V is no the end of hte world.

I hope these info helps.

Regards,
  Reply With Quote
Old 19th December 2012, 12:39 AM   #324
diyAudio Member
 
buzzforb's Avatar
 
Join Date: Oct 2010
Location: Burlington, NC
Secondary voltage times 1.3 is a very good estimate for Class A. Vdrop in this PSU will be minimal, as we will have a very small equivalent R of about .05omhs. That was main point of paralleling so many .47R resistors in the article. In theory, passing 50A will drop only 2.5V. Don't worry about it too much, as most folks wont leave a couple of watts very often.
__________________
...Shape the sound , Man!
  Reply With Quote
Old 19th December 2012, 01:16 AM   #325
diyAudio Member
 
buzzforb's Avatar
 
Join Date: Oct 2010
Location: Burlington, NC
I have most of my info pulled together. Will contact suppliers tomorrow to confirm qty available. Closing of the GB will happen some time tomorrow if all goes as planned. Emails will go out then.
__________________
...Shape the sound , Man!
  Reply With Quote
Old 19th December 2012, 01:53 AM   #326
diyAudio Member
 
buzzforb's Avatar
 
Join Date: Oct 2010
Location: Burlington, NC
Need some help. Could non US based GB members check to see if you can source 2SC 4793, so i don't have to pick an alternative.
__________________
...Shape the sound , Man!
  Reply With Quote
Old 19th December 2012, 09:34 AM   #327
diyAudio Member
 
Join Date: Jun 2010
Location: Gothenburg
It doesn't seem like the big companies carries it (Maplin, Radioshack, Farnell, Elfa, Conrad or Rapid).
Mouser did carry it, but won't have it in stock until March.

However, TME seem to have 4k+ pcs in stock and they source cheap Indel and Talema transformers as well.(I've never bought anything from them before but maybe someone else has some input on the store?)

EDIT:
AKSA mentioned in an old thread that MJE15030 might work as well as a replacement. It might be easier to source.

Last edited by backefel; 19th December 2012 at 09:39 AM.
  Reply With Quote
Old 19th December 2012, 10:03 AM   #328
diyAudio Member
 
Join Date: May 2012
Quote:
Originally Posted by buzzforb View Post
Need some help. Could non US based GB members check to see if you can source 2SC 4793, so i don't have to pick an alternative.
In F5 schematic, I cannot find 2SC4793.
  Reply With Quote
Old 19th December 2012, 11:18 AM   #329
diyAudio Member
 
Join Date: May 2012
I've found 2sc4793 in F5 turbo V3. There is 2sc4793 in v2 kit part, isn't there?
  Reply With Quote
Old 19th December 2012, 11:30 AM   #330
diyAudio Member
 
buzzforb's Avatar
 
Join Date: Oct 2010
Location: Burlington, NC
lehuy173,
Not trying to be ugly, but please take the time to read the article. It explains evrything very well, much better than I could. If you still have questions, I will be more than happy to answer them. I have solved the bjt issue, as I have found that I had 50 leftover from last Gb. so no issue there. Emails will go out later today to confirm all the info I have for everyone. Hopefully the parts can be here at the beginning of the year, and then it will just be a matter of waiting on the PSU boards. For those not getting them, kits will go out immediately.
__________________
...Shape the sound , Man!
  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
FS: Audiosector amp - chassis and premium kit Colin Swap Meet 1 29th October 2009 04:15 PM
My Vifa/Scan Speak Project - Solen Premium kit conscious Multi-Way 7 3rd December 2007 08:43 PM
AudioSector LM3875 dual mono premium kit. nodiak Swap Meet 1 16th October 2007 06:38 PM
FS: Audio Sector Premium LM3875 Kit Firebottle Swap Meet 2 23rd July 2006 08:46 AM
NIB BrianGT LM3875 Premium GC kit. Tony D. Swap Meet 9 1st September 2004 04:43 PM


New To Site? Need Help?

All times are GMT. The time now is 04:19 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