I'd like to weigh in on this topic with my 2 cents worth, being a long time QRP operator on various bands and modes...
I think QRP means soething different depending on what kind of operating you do. On HF, its generally 5 watts into a simple antenna, such as a dipole or vertical.
HF digital, there isnt much of a distinction (psk31) as many run 5 watts into a dipole vs maybe 20-30 watts into a similar antenna for QRO?
I operate VHF and microwave. to me, on 2m SSB tropo, I consider QRP to be 5-10 watts into whatever and however large an array you can muster, as most QRO stations run 50 watts or more into a similar antenna.
EME ops typically defines QRP as anything under about 500 watts or so into a single yagi. (no matter how large that single yagi is)
Meteor Scatter I've been called QRP running 50 watts into 10 elements.
However, on 10 GHz, I run 2 watts into a 18 inch offset fed dish, and I do NOT consider myself QRP. I'm an "average powered station" with that setup. When I ran 200 mW into the same dish, it was questionable even then if I could consider myself QRP. 2 watts = about 2-4KW ERP, 200 mw -= 200-400W ERP. (I havent actually MEASURED the gain, this is calculated ERP)
QRP is a relative term. Depending on what kind of operating you do, ERP certainly does take into account whether you're QRP or not.
I think in the satellite realm, I would understand QRP to be 5 watts or less into a low gain antenna. Maybe I'm wrong about this, as I'm still a relative newcomer, however This puts everyone on an even keel as far as someone stepping over another to make it fair for everyone. I know there are operators on the main channel that might tweak up the power to get thru on a busy channel. I know, because I have when I started out. I have realised it wasnt right, and now my power stays at 5 watts on the 857. Do i consider myself QRP on AO-51? well, with my homebrew 3 ele/6 ele V/u antenna on a fixed elevation mount, yea, at times I do, when running 5 watts. I actually have LESS antenna gain than someone would have with a handheld yagi because the antenna is hardly ever pointing right at the bird.
The QRP channel does provide some interesting experimentation like what Tim, N3TL and others have done, exploring "how low can you go" and still make contact. To me, THAT is the kind of experimentation that seems like a logical purpose for the "QRP" channel.
As a side note, hasnt the rule always been to run just enough signal to achieve a downlink of reasonable quality? I remember this from my AO-10 days. Too much power on an SSB bird robs power from everyone. Too much power on an FM bird robs others from getting in. Michael Heim Chief Engineer, Forever Broadcasting New Castle PA WKST WJST WWGY 814-671-0666 ARS KD0AR
----- Original Message ---- From: Sebastian w4as@bellsouth.net To: AMSAT BB AMSAT-BB@amsat.org Sent: Friday, December 19, 2008 11:10:45 PM Subject: [amsat-bb] Re: QRP re deux
I agree 100% with you Jim.
If you look at it another way. Standing on relatively flat terrain with 5 watts from an HT on a simplex channel will give you a mile or so on FM.
That same 5 watts from the same HT at the Empire State Building observation deck will give you coverage to several miles, if not several states.
Either of those two scenarios, I consider to be QRP.
73 de W4AS Sebastian
On Dec 19, 2008, at 6:49 PM, Jim Danehy wrote:
the premise that I follow is that QRP in the ham fraternity for decades prior to AMSAT was 5 watts output from the final stage of the transmitter . . . any other attempt which hopes to replicate that simplistic approach is speculation based upon a dynamic that is flawed from lack of accurate measurements . . . and constantly changing parameters . .
HAPPY HOLIDAYS
Jim W9VNE
_______________________________________________ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
I made my first 50 or so AO-51 contacts using my FT-60 with an offbrand equivalent of the Diamond NR770HA.
I quickly figured out that it was not a game of power for me, since at the time I did not have a way to use more power, but rather a game of timing.
BTW: With that omni, AO-51 came in at about an S2 at the most.
On Sat, Dec 20, 2008 at 6:51 AM, Michael Heim kd0ar@sbcglobal.net wrote:
I'd like to weigh in on this topic with my 2 cents worth, being a long time QRP operator on various bands and modes...
I think QRP means soething different depending on what kind of operating you do. On HF, its generally 5 watts into a simple antenna, such as a dipole or vertical.
HF digital, there isnt much of a distinction (psk31) as many run 5 watts into a dipole vs maybe 20-30 watts into a similar antenna for QRO?
I operate VHF and microwave. to me, on 2m SSB tropo, I consider QRP to be 5-10 watts into whatever and however large an array you can muster, as most QRO stations run 50 watts or more into a similar antenna.
EME ops typically defines QRP as anything under about 500 watts or so into a single yagi. (no matter how large that single yagi is)
Meteor Scatter I've been called QRP running 50 watts into 10 elements.
However, on 10 GHz, I run 2 watts into a 18 inch offset fed dish, and I do NOT consider myself QRP. I'm an "average powered station" with that setup. When I ran 200 mW into the same dish, it was questionable even then if I could consider myself QRP. 2 watts = about 2-4KW ERP, 200 mw -= 200-400W ERP. (I havent actually MEASURED the gain, this is calculated ERP)
QRP is a relative term. Depending on what kind of operating you do, ERP certainly does take into account whether you're QRP or not.
I think in the satellite realm, I would understand QRP to be 5 watts or less into a low gain antenna. Maybe I'm wrong about this, as I'm still a relative newcomer, however This puts everyone on an even keel as far as someone stepping over another to make it fair for everyone. I know there are operators on the main channel that might tweak up the power to get thru on a busy channel. I know, because I have when I started out. I have realised it wasnt right, and now my power stays at 5 watts on the 857. Do i consider myself QRP on AO-51? well, with my homebrew 3 ele/6 ele V/u antenna on a fixed elevation mount, yea, at times I do, when running 5 watts. I actually have LESS antenna gain than someone would have with a handheld yagi because the antenna is hardly ever pointing right at the bird.
The QRP channel does provide some interesting experimentation like what Tim, N3TL and others have done, exploring "how low can you go" and still make contact. To me, THAT is the kind of experimentation that seems like a logical purpose for the "QRP" channel.
As a side note, hasnt the rule always been to run just enough signal to achieve a downlink of reasonable quality? I remember this from my AO-10 days. Too much power on an SSB bird robs power from everyone. Too much power on an FM bird robs others from getting in. Michael Heim Chief Engineer, Forever Broadcasting New Castle PA WKST WJST WWGY 814-671-0666 ARS KD0AR
----- Original Message ---- From: Sebastian w4as@bellsouth.net To: AMSAT BB AMSAT-BB@amsat.org Sent: Friday, December 19, 2008 11:10:45 PM Subject: [amsat-bb] Re: QRP re deux
I agree 100% with you Jim.
If you look at it another way. Standing on relatively flat terrain with 5 watts from an HT on a simplex channel will give you a mile or so on FM.
That same 5 watts from the same HT at the Empire State Building observation deck will give you coverage to several miles, if not several states.
Either of those two scenarios, I consider to be QRP.
73 de W4AS Sebastian
On Dec 19, 2008, at 6:49 PM, Jim Danehy wrote:
the premise that I follow is that QRP in the ham fraternity for decades prior to AMSAT was 5 watts output from the final stage of the transmitter . . . any other attempt which hopes to replicate that simplistic approach is speculation based upon a dynamic that is flawed from lack of accurate measurements . . . and constantly changing parameters . .
HAPPY HOLIDAYS
Jim W9VNE
Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
participants (2)
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Andrew Koenig -
Michael Heim