Home
JAQForum Ver 24.01
Log In or Join  
Active Topics
Local Time 00:43 02 Jul 2025 Privacy Policy
Jump to

Notice. New forum software under development. It's going to miss a few functions and look a bit ugly for a while, but I'm working on it full time now as the old forum was too unstable. Couple days, all good. If you notice any issues, please contact me.

Forum Index : Microcontroller and PC projects : MM2: General purpose instrumentation PCB

     Page 2 of 2    
Author Message
bigmik

Guru

Joined: 20/06/2011
Location: Australia
Posts: 2947
Posted: 05:55pm 18 Jun 2015
Copy link to clipboard 
Print this post

Hi Steve,

I like that one... I didnt think, when I designed the BP170, to incorporate an Opto-isolator..

Whilst that one is a mosfet relay a standard Opto would have worked a treat as well..

in either case it is a moot point as the circuit I employed works and works well.

One criteria was that there was to be minimal components as space was at a premium, I think I could have squeezed a SMD version on the board but not a standard DIP chip.

Regards,

Mick



Mick's uMite Stuff can be found >>> HERE (Kindly hosted by Dontronics) <<<
 
centrex

Guru

Joined: 13/11/2011
Location: Australia
Posts: 320
Posted: 10:13pm 18 Jun 2015
Copy link to clipboard 
Print this post

Hi all
Re riston PCB material.
Jcar used to sell it but no longer, Acetronics do not answer the phone number listed on the web site.
I have never tried the Kinsten system, looks like I will have to give it a go. With riston I used a negative as the artwork, Kinsten I believe requires positive artwork. Price wise it appears to be on a par with what I used to pay for riston.

With regard to the led driver for the display I use the one on Bigmicks BP170 but with the transistor connected in the normal manner, into the collector out the emitter, works like a charm.

Regards
Cliff



Cliff
 
bigmik

Guru

Joined: 20/06/2011
Location: Australia
Posts: 2947
Posted: 11:07pm 18 Jun 2015
Copy link to clipboard 
Print this post

Hi Cliff,

  centrex said  
With regard to the led driver for the display I use the one on Bigmicks BP170 but with the transistor connected in the normal manner, into the collector out the emitter, works like a charm.


As is my recommendation (latest manual Located HERE )

Version 2 will have the transistor the correct way around..

Regards,

Mick
Mick's uMite Stuff can be found >>> HERE (Kindly hosted by Dontronics) <<<
 
centrex

Guru

Joined: 13/11/2011
Location: Australia
Posts: 320
Posted: 04:55pm 04 Jul 2015
Copy link to clipboard 
Print this post

Hi all
I have tried the Kinsten system and it works ok. Had a problem with a couple of broken tracks but I think it is not being used to the system.
I can readily get tracks 32 mills 0.8 mm wide with 16 mills 0.2mm spacing.
The broken track problem appears to be that the coating is easily scratched which allows the etchant to do its job.

To me it is not as good as what I was used to with Riston coated boards but it will probably get better with practice.

Cliff
Cliff
 
Bill7300
Senior Member

Joined: 05/08/2014
Location: Australia
Posts: 159
Posted: 04:14pm 30 Mar 2016
Copy link to clipboard 
Print this post

Ristron was negative resist. We used to use 3M reversal film to achieve the negative. Still have a carton of that film around here somewhere, along with a heap of Ristron pcb blank but unfortunately, the reversal film seems to have had a finite lifespan, as I have been unable to get it to develop. Maybe 30 years in storage was a tad long.

Aircraft builder at this end too, although I do have two flying 'planes to use as test beds. I have just found this discussion, so I am now anxiously trying to follow Peter's developments.
Bill
 
Bill7300
Senior Member

Joined: 05/08/2014
Location: Australia
Posts: 159
Posted: 11:28pm 31 Mar 2016
Copy link to clipboard 
Print this post

  matherp said   My boards arrived yesterday so I've built one up to test. Of course for a production environment the display and the RTC would be soldered direct rather than socketed and the board would only be populated to the extent required.




Everything seems to work well with the ILI9341 or




ILI9163.

There are a couple of changes I need to make for version 2. First I should have had a decoupling capacitor across the power pins of the MCP3424 ADC. Second, the silkscreening for the diodes is the wrong way round (thanks RS!).

In addition I've added a header for an openlog to the layout.

I'll continue to test and make changes to version 2

Update
Unfortunately the PWM control of the backlight doesn't work. I knew it might be an issue as I am trying to turn off a p-channel mosfet connected to 5V with a gate at 3.3V - it stays on
The next version will have to use a npn transistor to switch the mosfet




if required. If anyone wants one of the current version PCBs then send me a PM and and I'll pop one in the post. I have 8 spare.


Did you lay out a later version of this pcb, Peter?
Bill
 
     Page 2 of 2    
Print this page


To reply to this topic, you need to log in.

The Back Shed's forum code is written, and hosted, in Australia.
© JAQ Software 2025