[PPRAANet] Temperature Testing of "1 Watter"

[Paul Signorelli]

The sunspots are all gone and the weather outside is frightful.
i have several radios that were 'unqualified' for FYBO (Brrrr), Polar Bear (Grrrrr), and Winter Field Day,  (WFDeee) operations.

The temperature in COS dropped to +2 F last night and i  left my "1 Watter" rigs  outside overnight.
These radios have commercial parts in them, not MIL temperature range parts.

  I  tested the 1W20 (20 meter) and the 1W40 (40 meter) versions.
 One has NiCad's and the other LiIon cells.
My (1W20) '1 Watter'  is refitted into an old PRC319 military radio chassis.
See QRP Quarterly, October 2016, p. 20.
My 1W40 is in a very small LMB box with internal 14500 LiIon cells.

Both passed the test.
The 1W20 was running on a  1AH,  24V battery.
There was full power and no chirp.
The QRP Guys Frequency counter
< http://www.qrpguys.com/> was bright and right on frequency.

This rig has big knobs for gloved operation.
 The 1W40 internal battery was not fully charged and became discharged quickly.
It had low power output and a little chirp (599c) until I switched to an external battery.
The 1W40 worked fine with an external battery.
It has small switches that are hard to get at with gloves on but once set, gloves can be used.

  If you have not seen the "1 Watter" kit go to Diz's web site at:
< http://www.kitsandparts.com/1watter-V3.php>.

 3 years ago i put my PRC64, PRC74, PRC319's, plus my Elecraft KX1, outside for an overnight cold soak
 at -5F.  Some of my green radios were designed for -30F operation.
  i re-measured the Power and Frequency of each units in the morning while they were still cold.
i also checked the receiver sensitivity and modulation. They all passed.

This was a slow Thermal Soak not a Thermal Shock test.
(Thermal Shock can crack SMT solder joints...don't want to do that).
i measured the room temperature (+60F) RF Power output and Frequency prior to the test.

After testing i brought the radios back up to +60F in a low humidity room with the power removed
to prevent dendrite growth.
You don't want the radios powered as they go through the dew point.
You could do some testing like this using your home freezer but that could cause Thermo Shock damage.
 i wouldn't recommend any Thermo Shock testing unless you are prepared to fix your radio.

Now all the radios qualified I am ready to go, except for the 14,000 foot high altitude test, which is next.
Grrrr/Brrr/Wfdeee....
Here are last years 2016 FYBO Rules <http://www.azscqrpions.org/>, Feb. 4, 2017

and WFD is at: <https://www.winterfieldday.com/rules/>, Jan. 28/29, 2017.
Paul w0rw
Snowy Colorado