Welcome Guest! To enable all features please Login or Register.

Notification

Icon
Error

Options
View
Go to last post Go to first unread
KOHTOPA  
#1 Posted : Saturday, November 25, 2006 6:55:47 PM(UTC)
KOHTOPA

Rank: Member

Groups: Customer, Beta Testers
Joined: 11/25/2006(UTC)
Posts: 12

I've built integrated amp using Darwin, Kooka, RevC.
Now I'm planning to add LCD to the amp. Actually two of them :)
One will serve as a VU meter the other one as a Spectrum
Monitor.

My question is - what is the best connection point for LCD?
How is it usually implemented to reduce distortion/impact
on the signal? What's the max amplitude/voltage of the signal
in that point? LCD boards will be PIC based. So, the signal will
go to the PIC's DAC.
Thanks!


Russ White  
#2 Posted : Monday, November 27, 2006 4:10:03 PM(UTC)
Russ White

Rank: Administration

Groups: Administration, Customer
Joined: 10/24/2006(UTC)
Posts: 3,979
Location: Nashville, TN

Thanks: 25 times
Was thanked: 89 time(s) in 83 post(s)
KOHTOPA wrote:
My question is - what is the best connection point for LCD?
How is it usually implemented to reduce distortion/impact
on the signal? What's the max amplitude/voltage of the signal
in that point? LCD boards will be PIC based. So, the signal will
go to the PIC's DAC.
Thanks!


Thats a loaded question. :)

I would have to know exactly what you are trying to measure.

Is it the output of the revC?

If so then you really only have one choice, at the output connector.

As long as your PIC based circuit is well isolated and has a high input impedance you should have no discernible degradation in sound quality.

Cheers!
Russ
KOHTOPA  
#3 Posted : Monday, November 27, 2006 5:31:52 PM(UTC)
KOHTOPA

Rank: Member

Groups: Customer, Beta Testers
Joined: 11/25/2006(UTC)
Posts: 12

> Is it the output of the revC?

This is the question :)
Where should I fit my LCD-based VU meter? What is the usual
point? Is it between Kooka and RevC or after RevC? What is the
signal amplitude in that point?
How is such connection usually implemented - how to provide
that isolation and high inpedance?
Thank you!

Russ White  
#4 Posted : Wednesday, November 29, 2006 6:51:44 AM(UTC)
Russ White

Rank: Administration

Groups: Administration, Customer
Joined: 10/24/2006(UTC)
Posts: 3,979
Location: Nashville, TN

Thanks: 25 times
Was thanked: 89 time(s) in 83 post(s)
KOHTOPA wrote:
> Is it the output of the revC?

This is the question :)
Where should I fit my LCD-based VU meter? What is the usual
point? Is it between Kooka and RevC or after RevC? What is the
signal amplitude in that point?
How is such connection usually implemented - how to provide
that isolation and high inpedance?
Thank you!



Sorry for the late reply, but I would think it would be very dependant on the VU circuit you are using. So if the VU circuit have a rather low maximum voltage input (say < 10VPP) in that case it would have to go between the kooka and the revC.

As long as the VU circuit has its own PS and a high input impedance (I would have to see the circuit to give you any real guidance) it should be pretty well isolated. Just be careful with your GND wire (only connect it at one spot).

Sounds like a fun project, if you have a schematic or anything for me to look at I can help more.

Keep us posted! :)

Cheers!
Russ
KOHTOPA  
#5 Posted : Friday, December 1, 2006 4:51:55 PM(UTC)
KOHTOPA

Rank: Member

Groups: Customer, Beta Testers
Joined: 11/25/2006(UTC)
Posts: 12

I don't have any schematics right now. I'm just collecting
all nesessary info :) Here is the image depicting
one of the possible implementations using Crystalfontz graphics
128*64 LCD with blue backlight.

This is just my hand-made image it's not a photo :)
KOHTOPA attached the following image(s):
vu.jpg (55kb) downloaded 136 time(s).

You cannot view/download attachments. Try to login or register.
Rss Feed  Atom Feed
Users browsing this topic
Forum Jump  
You cannot post new topics in this forum.
You cannot reply to topics in this forum.
You cannot delete your posts in this forum.
You cannot edit your posts in this forum.
You cannot create polls in this forum.
You cannot vote in polls in this forum.