Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Solid State Talk all about solid state amplification.

Just another lateral FET amp
Just another lateral FET amp
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 30th July 2019, 06:31 PM   #21
voltwide is offline voltwide  Ireland
diyAudio Member
 
Join Date: Jan 2010
Now there is some work in progress....
__________________
tuby or not tuby, that is here the question!
  Reply With Quote
Old 30th July 2019, 08:38 PM   #22
rsavas is offline rsavas  Canada
diyAudio Member
 
Join Date: Aug 2012
Location: Ontario
I have been using JLCpcb for a while now, I think they are great for what they are worth. Cheaper than pcbway, so I am sticking with them.
I have had no data load rejections to date. I made a mistake once and caught it early enough to contact them to scrap the design before it got into production.
I can get them delivered fast with DHL express and pay duties/brokerage or the really slow way with DHL post I guess it is, but it comes via Canada Post and no brokerage/duties.

Good luck with your design voltwide, nice to see pics of your work, I can see how much more assy is required for a TO-3 metal can vs a TO-264 as I have used.

Last edited by rsavas; 30th July 2019 at 08:41 PM.
  Reply With Quote
Old 30th July 2019, 10:00 PM   #23
voltwide is offline voltwide  Ireland
diyAudio Member
 
Join Date: Jan 2010
Thank you for the kind wording.

Quote:
Originally Posted by rsavas View Post
I can see how much more assy is required for a TO-3 metal can vs a TO-264 as I have used.
You can see some good reason why this case is obselete
__________________
tuby or not tuby, that is here the question!

Last edited by voltwide; 30th July 2019 at 10:04 PM.
  Reply With Quote
Old 30th July 2019, 10:03 PM   #24
voltwide is offline voltwide  Ireland
diyAudio Member
 
Join Date: Jan 2010
Meanwhile the first module is populated.
Attached Images
File Type: jpg 07_module1_top_IMG_20190730_224130773.jpg (172.9 KB, 229 views)
File Type: jpg 08_module1_bot_IMG_20190730_224111769.jpg (192.7 KB, 218 views)
__________________
tuby or not tuby, that is here the question!
  Reply With Quote
Old 30th July 2019, 10:05 PM   #25
nigelwright7557 is offline nigelwright7557  United Kingdom
diyAudio Member
 
nigelwright7557's Avatar
 
Join Date: Apr 2008
Location: Carlisle, England
Quote:
Originally Posted by voltwide View Post
Thank you for the kind wording.


You see a good reason why this case is obselete
I found I could use my pcb as a drill template and get very good results.
I line up pcb with heatsink then clamp pcb to heat sink.
I then drill one of the transistor mounting bolt holes.
I put a bolt through the hole and tighten it down.
I then drill opposite end of heatsink and bolt that down.
You can now drill out rest of the holes through the pcb (with care.)
I have done quite a few this way and never had a problem.
I found for the connecting wire holes a hand held drill was better to stop the drill biting in the wrong place. I put the drill through the pcb hole and start it up slowly.
They are a pain and much harder than single hole transistors but nothing wrong with a bit of nostalgia !
__________________
PCBCAD51 and PCBCAD360 out now >>> https://www.murtonpikesystems.co.uk
  Reply With Quote
Old 30th July 2019, 10:07 PM   #26
rsavas is offline rsavas  Canada
diyAudio Member
 
Join Date: Aug 2012
Location: Ontario
The case is not really obsolete but certainly not used as much as the past with the newer plastic. TO-3 are more reliable as they are hermetically sealed, so no or little moisture absorption to contaminate in the pressure cooker test.
  Reply With Quote
Old 30th July 2019, 10:08 PM   #27
voltwide is offline voltwide  Ireland
diyAudio Member
 
Join Date: Jan 2010
Quote:
Originally Posted by Walkalone View Post
Hi Voltwide,
How is the quality of these PCBs? I've ordered many PCBs from Chinese but there is no anywhere i actually feel OK.

Regards,
Cuong Nguyen
I cannot complain about quality - it is fine. Being a "coarse" design with much clearance requirements are relaxed and it is hard to manufacture scrap.
__________________
tuby or not tuby, that is here the question!
  Reply With Quote
Old 30th July 2019, 10:16 PM   #28
voltwide is offline voltwide  Ireland
diyAudio Member
 
Join Date: Jan 2010
Quote:
Originally Posted by nigelwright7557 View Post
I found I could use my pcb as a drill template and get very good results.
I line up pcb with heatsink then clamp pcb to heat sink.
I then drill one of the transistor mounting bolt holes.
I put a bolt through the hole and tighten it down.
I then drill opposite end of heatsink and bolt that down.
You can now drill out rest of the holes through the pcb (with care.)
I have done quite a few this way and never had a problem.
I found for the connecting wire holes a hand held drill was better to stop the drill biting in the wrong place. I put the drill through the pcb hole and start it up slowly.
They are a pain and much harder than single hole transistors but nothing wrong with a bit of nostalgia !
I do not take the pcb as a stencil but a 1:1 printout from my laser printer, which is sufficiently accurate. With paper stencil I punch-mark and then drill. This is less convenient but I avoid any ugly damage of the pcb.
__________________
tuby or not tuby, that is here the question!
  Reply With Quote
Old 30th July 2019, 10:20 PM   #29
nigelwright7557 is offline nigelwright7557  United Kingdom
diyAudio Member
 
nigelwright7557's Avatar
 
Join Date: Apr 2008
Location: Carlisle, England
Quote:
Originally Posted by voltwide View Post
I do not take the pcb as a stencil but a 1:1 printout from my laser printer, which is sufficiently accurate. With paper stencil I punch-mark and then drill. This is less convenient but I avoid any ugly damage of the pcb.
If you go gently the hole aligns the drill into it.
Also, using an electric hand drill with the drill down the hole before you start stops the pcb hole being widened out.
__________________
PCBCAD51 and PCBCAD360 out now >>> https://www.murtonpikesystems.co.uk
  Reply With Quote
Old 30th July 2019, 10:30 PM   #30
voltwide is offline voltwide  Ireland
diyAudio Member
 
Join Date: Jan 2010
Some remarks to the actual pcb layout. Being 2-sided big copper filled areas are possible. So I divided the amp into 2 zones: the input zone with LTP ending at the input of the VAS. All nets of this area carry little voltage levels, so they are screened by a copper fill connected to analog GND.
The second zone is the power, carrying all the nets at the high output level. This includes the VAS output as well. This hole area is screened by a copper plane connected to the output. The idea behind this is to minimize the parasitic capacitive loading of the VAS by the well known method of an active screen.
The top view of the pcb shows these two areas, separated by a wide trench acting as "isolation barrier".

And this isolation barrier is bypassed by a minimized bunch of tht resistors and caps.
__________________
tuby or not tuby, that is here the question!
  Reply With Quote

Reply


Just another lateral FET ampHide 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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Lateral MOSFETs JaredC79 Solid State 79 1st March 2016 10:39 AM
double die lateral fet vandenberg Swap Meet 2 20th November 2013 03:28 PM
Lateral F4/BA buzzforb Pass Labs 16 21st October 2011 04:30 AM
Lateral FET and Rds on? AndrewT Everything Else 2 27th December 2005 08:05 PM
lateral vs vertical,P vs N Leolabs Pass Labs 3 15th February 2005 07:01 PM


New To Site? Need Help?

All times are GMT. The time now is 07:45 AM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 14.29%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Copyright ©1999-2019 diyAudio
Wiki