[Skimmertalk] Red Pitaya set up with N6TV's instructions

[dd5xx at web.de]

> I tried the script Bob mentioned on his tutorial, but unfortunately it did not work on the latest Alpine OS SDcard image.

Hello again,

I looked into Bobs' script and I think I know why it fails when I try to run it:
if one use Pavel's latest SDcard image which runs GNU/Linux Alpine the default shell is "ASH" and not "bash". You can check it with the shell prompt command "echo $SHELL". So you need to modify Bob's shebang (1st line in script xadc.sh) and change it to

#!/bin/ash

Because ASH shell is using other syntax the following voltage function fails, too. But I don't care about the voltages at the moment so I commented out these lines. The whole script looks like that:

----BEGIN-----

#!/bin/ash

# path to IIO device
XADC_PATH=/sys/bus/iio/devices/iio:device0

################################################################################
# temperature
################################################################################

OFF=`cat $XADC_PATH/in_temp0_offset`
RAW=`cat $XADC_PATH/in_temp0_raw`
SCL=`cat $XADC_PATH/in_temp0_scale`

FORMULA="(($OFF+$RAW)*$SCL)/1000.0"
VAL=`echo "scale=2;${FORMULA}" | bc`
echo "in_temp0 = ${VAL} ..C"

-----END------

I am running it now with "watch ./xadc.sh" so the script is invoked each 2 seconds and I see the actual temperature. In the background the task "sdr_transceiver_hpsdr" is running so I will monitor the temperature for a while. After 10 minutes it is ~66 ° C. I am using the aluminium case without any fan. So in my humble opinion this should be sufficient, shouldn't it ?

Best 73
Saki, DD5XX



Gesendet: Mittwoch, 04. Oktober 2017 um 22:37 Uhr
Von: "Wes Cosand" <wes.cosand at gmail.com>
An: dd5xx at web.de
Cc: skimmertalk <skimmertalk at contesting.com>
Betreff: Re: [Skimmertalk] Red Pitaya set up with N6TV's instructions

Hi Saki:
 
I am using an old 12 volt power supply from a dead laptop to power my fan.  It is quite noisy but it is in the basement.  I am no expert but the FPGA chip gets hot, even with the aluminum, case as Bob has documented.  I would be hesitant to run it on 6 bands without a fan. 

But you can measure the temperature yourself with the Linux script that Bob documents on his web page.
 
Wes WZ7I