PI Project update

[Anonymous]

Hi Eric
I think you are right about OFC Eric. What do you think about noises of resistors? Should we use metal-film resistors in all stages of detector? or only for pre-amp and filters?
Andrew

 

[Anonymous]

Hi Andrew,
I use metal film resistors as a matter of course. The price is not much different to carbon film and you get 1% tolerance, lower noise, higher reliability and long term stability.
Eric.

 

[Anonymous]

Carl, with reference to those big honkin' Caps have you ever thought of soldering them to the reverse side of the board this can be done by either....>
Option A. Using a double sided board and on the component side removing all the copper except for the pads to the caps thus allowing them to be inserted into the board from the 'solder side'(you will however need to ensure continuity best method is either through hole plating[not an option to many] an eyelet [again not open to many] or by drilling a small hole next to the pad and running a link from the component side to the solder side (although slightly complex this option would be open to all)
or
Option B. By Firstly bending the legs of the caps at rightangles, covering the caps in heatshrink (to insulate them) laying them parrallel to the board and placing the bent legs onto the pads for This of course is the lest complex BUT does mean that you have two leads running parrallel, half the diameter of the caps in which to induce some noise
either of these methods would have to be better than remotely mounting the Caps .....what do you think? for that matter what does anybody think???

 

[Anonymous]

Good to see you drop by...
Yes, I've reverse-mounted devices before. The problem I ran into, and did not really expend any gray matter trying to resolve, was that I could not get the to cap leads in the same location. So I just stuck them where I could, with the expectation of wiggling in the cap wherever it would fit. That could include the back side of the board.
- Carl