serin resistors

[k_shirtcliffe]

I notice that on the rudolph infra red upgrade kit there aren't any serin 10/22k resistors.

The circuit diagram can be seen on page 39 of the following file http://www.rev-ed.co.uk/docs/axe107.pdf

Why is this? I thought that these were essential for proper operation?

Does this mean that if I am creating a board for my students which *does not* have a download/serin socket, I do not need to have the 10/22k resistors?

Thanks a lot,
- k e v -

 

[inglewoodpete]

Hi Kev,
Check the documentation for the Rudolph kit. <A href='http://www.rev-ed.co.uk/docs/AXE107.pdf' Target=_Blank>External Web Link</a>
In particular, page 39, &quot;Infra-red Upgrade PCB&quot; point 9.

 

[Michael 2727]

The serin nees to be tied to neg to prevent the chip from locking up, thinking a new
D/L was on the way.
The use of a 10K is just good practice,
<b>yanno what kids are like, anthing could happen </b> .