View Single Post
Old 28th Feb 2005, 6:19 pm   #26
David_Robinson
Pentode
 
David_Robinson's Avatar
 
Join Date: Feb 2004
Location: Nottingham, UK
Posts: 94
Default Re: Multi-Channel VHF Modulator Design

Quote:
Originally Posted by oldeurope
... programm the PIC. I am not able to do this.
If you want to build this design I can send you the programming file. You just need a PIC programmer (mine cost about 50).
Quote:
The leak current of this cap can change the bias!
The cap I used is a ceramic chip (surface mount) not an electrolytic. The leakage is very low.
Quote:
... place the electrolytic from the bias pot to ground to block noise from the 5V.
Good point although I haven't noticed a problem.
Quote:
Originally Posted by flyback
... your video should be band limited to ~3.0MHz, is this somthing that you have found is a problem?
Well, keep this to yourself as it is very hush-hush, but I am developing a standards converter too, and this produces the input video bandwidth times 405/625 which is a bit more than 3MHz...
__________________
Look that up in your Funk and Wagnall's

Last edited by Dave Moll; 27th Jun 2007 at 10:23 pm. Reason: correct for username change in quote
David_Robinson is offline