[arm-allstar] I think I found a new BF-888s board, need help finding COS

[Doug Crompton]

Andy,

  There have been many iterations of the 888 but in all cases they retain
the 8 pin chip where COS is picked up. I am attaching a photo from the
howtos at hamvoip.org showing the chip. There are two 8 pin chips and part
numbers are often hard to find. One of them is the spot - pin 1. Placement
of the chips changes so you will need to check which one it is. The COS
goes high on signal - 0V no signal, >2.5V signal.  If you cannot find a
connection on the circuit side you will have to remove the board to get to
the chip. Info on doing that is in the howto.


*73 Doug*

*WA3DSP*

*http://www.crompton.com/hamradio <http://www.crompton.com/hamradio>*


On Sat, Aug 11, 2018 at 12:38 PM, "Andrew Hull KE8HEV via arm-allstar" <
arm-allstar at hamvoip.org> wrote:

> Hello All,
> I'm in the process of building a simplex node (RA-40 & BF-888s).
>
> The BF-888s that I received has a date stamp on the board of 2017-11-04. I
> believe that this is an updated revision from the board that Chris Hood
> documents here:
> http://www.chrishoodblog.com/allstar-node-with-bf-888s-short-board/
>
> The design looks similar enough that the RX Audio, PTT, and Mic Audio
> appear to be in the same places. However, I'm at a loss for COS.
>
> Has anyone already solved the mystery for this revision? My Google attempts
> have turned up nothing.
>
> If not, could anyone offer some advice on how to find it myself? I consider
> myself in the "knows enough to be dangerous" category of low level
> electronics. So, with a friendly shove in the right direction, I hope I can
> find it.
>
> Here's a photo of my board. I haven't taken it off the heatsink to get a
> look at the other side.
> https://photos.app.goo.gl/pcnRfK2X7Pt8HhXKA
>
> Thank you!!
>
> 73,
> Andy
>
> --
> Andy Hull
> KE8HEV
>
> [Any errors in spelling, fact, or tact are transmission errors]
> _______________________________________________
>
> arm-allstar mailing list
> arm-allstar at hamvoip.org
> http://lists.hamvoip.org/cgi-bin/mailman/listinfo/arm-allstar
>
> Visit the BBB and RPi2/3 web page - http://hamvoip.org
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.hamvoip.org/pipermail/arm-allstar/attachments/20180811/c0b0ba8c/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: cos.jpg
Type: image/jpeg
Size: 98859 bytes
Desc: not available
URL: <http://lists.hamvoip.org/pipermail/arm-allstar/attachments/20180811/c0b0ba8c/attachment-0001.jpg>