November 22, 2011

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"RF Power Measurement for QRPers"

Online chat discussion log ...
<20:34:32>"George - N2APB": See more on the Micro908 Antenna Analyzer at
<20:44:09>"George - N2APB": Regen info: Australian mag:  google "Lamphouse One"
<20:57:04>"George - N2APB": Possible missing wire going to the SDR Cube's rear panel connector?
<20:58:22>"George - N2APB": Computations for R in the Micro908
<21:04:40>"Joe - N2CX": Simple audio headsets work fine as well
<21:05:27>"George - N2APB": Sony USB Audio UAB-260 ... Milt is using
<21:06:04>"George - N2APB": Joe is using $20 headset from Staple.  Also used headset from iPod Touch.
<21:06:32>"George - N2APB": Chuck is using an extended telephone speaker + wire.
<21:07:26>"George - N2APB": At top of the Touch platform, in center/top, click on the Events tab, and then behind it is a tab for the channel messages
<19:59:23>"Bill - KD5TFD": Someone was asking for refs on DSP earlier ..."Understanding DSP" by Richard G Lyons is a pretty good text
<20:05:15>"Ray K2ULR": It's also a help to use headsets... keeps feedback from doubling away!
<20:16:26>"Joe - N2CX": info on njqrp meeting at
<20:18:29>"Bill - KD5TFD": I've used a WM2
<20:18:46>"Chuck-WA6LTV": HI GEORGE TESTING IPOD TOUCH 4, text messaging .
<20:18:54>"Milt-W8NUE": QRP Wattmeter Kit from K5BCQ kits
<20:19:13>"LarryW2LJ": I have the OHR WM1
<20:19:37>"Joe - N2CX": NORCAL had one though it is snow out of stock
<20:20:06>"Bill - KD5TFD": link for the wm2:
<20:20:21>"Joe - N2CX": NOGA sold the NOGAWATT dual meter DIY kit
<20:31:31>"Jim - N2ADR": Turn off voice prompting: menu   Self/Sound Pack/ Sounds Deactivate
<20:32:46>"John - KE3S": I think it's notification sounds on the iPad.
<20:34:26>"Joe - N2CX": TO220 package!
<20:38:35>"Ray K2ULR":
<20:38:52>"Dave AA3UR": Ohmite
<20:41:06>"Joe - N2CX": HP 431 i think
<20:41:24>"Joe - N2CX": 410 C is a VTVM
<20:43:17>"Milt-W8NUE": bolometer, not thermocouple???
<20:43:27>"Joe - N2CX": Hi accuracy at mw power levels and easy to burn out!
<20:44:15>"Jim - N2ADR": Resistive power meters have almost infinite frequeny response
<20:46:56>"George - N2APB": KangaUSA Kits ...
<20:47:20>"George - N2APB": Elecraft W1 Power Meter ...
<20:51:04>"George - N2APB": Great power reference chart .... QRP Quarterly magazine for Spring 2003, page 42
<20:51:51>"Bruce - N1RX": DBM chart:
<20:55:30>"John - KE3S": NT7S QRP-L Rig test procedures sheet 11 has that conversion chart you mentioned.
<20:58:58>"Bill - KD5TFD": Jackson Harbor battery kit:
<21:00:58>"George - N2APB": Battery power-off timer circuit ....
<21:01:41>"Joe - N2CX": WB9KZY Chuck Olson Jackson harbor
<21:01:52>"Ray K2ULR": $4.50 plus shipping
<21:03:01>"Bruce - N1RX": cool. nice and cheap
<21:04:30>"George - N2APB": Bruce really recommends the circuit from Jackson Harbor Press ...
<21:09:50>"George - N2APB": Simple RF-Power Measurement, Making power measurements from nanowatts to 100 watts is easy with these simple homebrewed instruments ... June 2001 QST, page 38
<21:12:22>"Milt-W8NUE": +7dBm = 5mW
<21:14:09>"Bruce - N1RX": home-brew 40dB tap:
<21:30:45>"Bill - KD5TFD":
<21:32:55>"Bill - KD5TFD": SSDRA .. only $173 from:
<21:33:01>"Bill - KD5TFD": No -- out of print
<21:33:07>"Bill - KD5TFD": but has a pic of the book
<21:48:31>"Jim - N2ADR": ARRL Arduino book Pay $75/page, deadline June 1; email; they need more authors!
<21:52:10>"Joe - N2CX": George, the ARISSAT was what Steve Bible discussed at DCC
<21:54:45>"Douglas KA2UPW": Here's some links:  See the current satellite position of ARISSat-1 at
<21:57:35>"Douglas KA2UPW": Latest live telemetry from the satellite (updated from ground stations around the planet) is at
<21:59:13>"Douglas KA2UPW": last one... the live-from-orbit slow scan TV pictures from ARISSat-1 are at
<22:02:03>"Ray K2ULR": What about that "Fireball" rig??
<22:03:04>"George - N2APB": Too simplistic
<22:06:49>"Bill - KD5TFD": rasberry Pi potentially an interesting board for such a project.
<22:07:17>"George - N2APB": Been looking at Cypress SoC
<22:09:30>"Mike N2EAB": A KD1JV MMR-40 type xcvr, adapted for10m?
<22:10:26>"Douglas KA2UPW": My Dollar store special:  16' tape measures to use as ground radials
<22:15:53>"Joe - N2CX": Joe Jesson, the MiniCircuits pwr meter is $700 !!!!!!!
<22:17:01>"Joe - N2CX": That is the RF power transistor - big brother to the ones in the PennyWhistle.
<22:20:31>"Bill - KD5TFD": here here .. big thanks to Jeremy NH6Z for the server
<22:23:36>"Mike N2EAB": Thank you for making this forum available! 73