[amsat-bb] Re: ERP is not QRP apples and oranges

n3tl@bellsouth.net n3tl at bellsouth.net
Fri Dec 19 20:04:16 PST 2008


Jim and all,

"after all the goal is to allow those with lesser powered rigs (HT) to have a channel on AO 51 where they could be more competitive with restricted power . . . "

Maybe Drew, Gould or someone else will comment on this. I've never heard any control operator or member of the AO-51 scheduling team state that as a reason for a "QRP" frequency pair. The first time they activated that pair after I started working the satellites, I didn't jump in with my 5 watts and Arrow. I tried the AL800 whip, then 300 milliwatts, then 50 milliwatts on Duracells. And when they all worked over there, I took 'em to 145.920/435.300 - and they worked there, too. They also worked on AO-27 and SO-50 ... all of them not just once or twice, but repeatedly.

I guess that's why I personally have never felt "less competitive" on the "regular" AO-51 pair when I'm running 5 watts into a handheld antenna with gain and directional radiation. 

73 to all,

Tim
-------------- Original message from "Jim Danehy" <jdanehy at cinci.rr.com>: -------------- 

AMSAT started using the term QRP when they probably should have used ERP or more accurately "estimated" ERP . . . after all the goal is to allow those with lesser powered rigs (HT) to have a channel on AO 51 where they could be more competitive with restricted power . . . maybe a better interpretation of ERP should be ESTIMATED RESTRICTIVE POWER rather than EFFECTIVE RADIATED POWER which in amateur radio is more speculative than accurate as I have attempted to point out in prior posts . . . unfortunately when I run 5 watts output on AO51 "QRP" channel I only have one set of satellite antennas to use . . .I could . . .( might be interesting ) use my Bird 25 watt 2 meter slug . . . on the other side of the attenuator (which I built years ago 10 db) so I could use 1/2 watt Uplink to my 10 db antenna or 50 watts estimated ERP . . .before I do that I 
> think I will attempt my last ham goal, EME . . . 
> 
> Jim W9VNE 
> 
> 
> ----- Original Message ----- 
> From: Jim Danehy 
> To: n3tl at bellsouth.net 
> Sent: Friday, December 19, 2008 9:40 PM 
> Subject: Re: [amsat-bb] ERP is not QRP apples and oranges 
> 
> 
> AMSAT started using the term QRP when they probably should have used ERP or 
> more accurately "estimated" ERP . . . after all the goal is to allow those with 
> lesser powered rigs (HT) to have a channel on AO 51 where they could be more 
> competitive with restricted power . . . maybe a better interpretation of ERP 
> should be ESTIMATED RESTRICTIVE POWER rather than EFFECTIVE RADIATED POWER 
> which in amateur radio is more speculative than accurate as I have attempted to 
> point out in prior posts . . . unfortunately when I run 5 watts output on AO51 
> "QRP" channel I only have one set of satellite antennas to use . . .I could . . 
> .( might be interesting ) use my Bird 25 watt 2 meter slug . . . on the other 
> side of the attenuator (which I built years ago 10 db) so I could use 1/2 watt 
> Uplink to my 10 db antenna or 50 watts estimated ERP . . .before I do that I 
> think I will attempt my last ham goal, EME . . . 
> 
> Jim W9VNE 
> 
> 
> 
> 
> 
> ----- Original Message ----- 
> From: n3tl at bellsouth.net 
> To: Jim Danehy ; amsat-bb at amsat.org 
> Sent: Friday, December 19, 2008 8:17 PM 
> Subject: Re: [amsat-bb] ERP is not QRP apples and oranges 
> 
> 
> Amen, brother. 
> 
> Something occurred to me earlier today in thinking about this ongoing 
> discussion that includes a few different threads. 
> 
> Given all the information I can find about the nominal transmitter powers of 
> the satellites I have worked [AO-7, AO-16, AO-27 (currently inactive), AO-51, 
> FO-29, SO-50 and VO-52], at least half of every satellite contact I've made has 
> been QRP - the half coming this way from space. Most of mine - but not all - 
> have been 2-way QRP. 
> 
> 73, Merry Christmas and Happy New Year to all, 
> 
> Tim - N3TL 
> 
> 
> -------------- Original message from "Jim Danehy" : 
> -------------- 
> 
> ERP is not QRP . . . . . . I never saw anything in FCC exams about QRP or 
> > ERP but it has been a long time for me since I was last examined . . . 
> > folks are confusing ERP and QRP . . . 5 watts out QRP driving an amp . . 
> . get real . . . it is 5 watts out of the final stage feeding the antenna . . . 
> the gain of the antenna does not have anything to do with QRP it has to do with 
> ERP . . . one is apples and the other is oranges . . . the original issue arose 
> out of someone feeling that folks using the AO 51 QRP channel were not using QRP 
> . . . well I use 5 watts on the QRP channel but I only have fairly big yagis for 
> satellites . . . If the goal is to have HT users with compromised antennas use 
> the "QRP" channel then drop the QRP designation and ask the users to keep the 
> power to 5 watts out from the final stage of the transmitter and then WHAT ? ? ? 
> 5 watts many can compute but that is it . . . ERP is guess work by most . . 
> > . that is my point . . . seems senseless to me but surprising the 
> responses . . 
> > . ERP is not QRP different concepts . . . apples and oranges . . . . 
> > 
> > Jim W9VNE 
> > _______________________________________________ 
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> _______________________________________________ 
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