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Vintage Amateur and Military Radio Amateur/military receivers and transmitters, morse, and any other related vintage comms equipment. |
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22nd Jul 2021, 5:17 pm | #1 |
Dekatron
Join Date: Apr 2019
Location: Worthing, West Sussex, UK.
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What is QRP?
What is QRP in relation to radio/ham radio ?
David |
22nd Jul 2021, 5:22 pm | #2 |
Dekatron
Join Date: Apr 2012
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Re: What is QRP
"Low Power".
Precisely what 'low power' means depends.... in the US where Kilowatt stations are commonplace. 100 Watts can be considered QRP. Here in the UK, QRP is generally seen as under-ten-watts; some would say under-five-watts. See the G-QRP club site: http://www.gqrp.com/about.htm |
22nd Jul 2021, 5:29 pm | #3 |
Dekatron
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Re: What is QRP
QRP is the three letter 'Q' code which means either ''Shall I reduce power?" when used as a query and "Yes, Reduce Power" when used as an answer.
A list of 'Q' codes here:- https://www.giangrandi.org/electroni...io/qcode.shtml You might wonder why anyone would say 'QRP' when they could just say 'Reduce Power' but all of this goes back to the Morse only days when sending whole words was a fairly slow business, so abbreviations and codes like the 'Q' code were used frequently. When used in the context of 'QRP operation', generally speaking it means 'working using only low transmitter power'. For HF, this may be 5 watts or less and often much, much less especially with respect to CW / Morse operation. Even in these days of mainly voice operation you will still hear people saying 'Q' codes such as 'QTH', 'QSL', 'QRT' and so on. -Crossed with G6Tanuki. |
22nd Jul 2021, 5:30 pm | #4 |
Dekatron
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Re: What is QRP
Then you get "flea power", just a few milliwatts.
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22nd Jul 2021, 5:33 pm | #5 |
Nonode
Join Date: Jun 2013
Location: Surbiton, SW London, UK.
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Re: What is QRP?
And that is designated QRPp, 1 watt or less.
The leading UK amateur radio retailer ran an advert stating "Life's too short for QRP" ! |
22nd Jul 2021, 6:00 pm | #6 |
Moderator
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Re: What is QRP?
Go back to the origins.
QRP is a Q-code QRP = please reduce your power QRP? = Shall I reduce my power. QRO is the opposite, increase. QRP has become a synonym for low power operation. S meter scales and hence signal reports are close to logarithmic. You can reduce power quite a bit and yet get only small seeming reduction in signal report (assuming they were given honestly in the first place) Conversely you have to make very large increases in power to get much of an increased report. Where the whole thing comes unstuck is where there are large levels of background noise, like the now ever present fug from SMPS in light bulbs and gizmos of all sorts. For a listener in such an environment, intelligibility drops rapidly as a signal comes down to and below the noise floor. On the whole, CW Morse has become the main mode. There are QRP specialist clubs around the world G-QRP in the UK, QRP-ARCI in the US, OK-QRP in the Czech republic, and so on. On the whole they are a pretty friendly bunch without that hard edge of gamesmanship you may find in some contesters. David David
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22nd Jul 2021, 6:42 pm | #7 |
Moderator
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Re: What is QRP?
Most amateur radio has lost the home construction ethos, but I understand most QRP activities involve home constructed kit. In that sense, the culture is close to that of UKVRRR.
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22nd Jul 2021, 7:38 pm | #8 |
Dekatron
Join Date: Apr 2012
Location: Wiltshire, UK.
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Re: What is QRP?
I'd actually say that modern digital-modes like FT8 are the logical succession of hand-generated CW QRP: it's amazing just how far you can work with a few Watts on FT8 etc.
'Writing DSP code" is 21st-century home-construction. |
22nd Jul 2021, 11:05 pm | #9 |
Dekatron
Join Date: Apr 2019
Location: Worthing, West Sussex, UK.
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Re: What is QRP?
Thank you all, I know a lot more now about QRP, I had previously seen it referenced as Low Power but did not really understand in what context. I do not fully understand all of it but it is very interesting.
David |
22nd Jul 2021, 11:05 pm | #10 |
Nonode
Join Date: Nov 2015
Location: Welwyn Garden City, Hertfordshire, UK.
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Re: What is QRP?
I will submit that FT8 and most other digital modes are far from that.
A computer gives you massive processing gain so the radio path can be 20-30dB weaker than needed for simple hand sent CW (Morse). You work 10-100x as far? Big surprise! Your DX is no prize at all. It has some interest but that is all. You can work CW by your own efforts and you can homebrew the TX/RX and/or use surplus or historic gear. Otherwise you can download or code the digital stuff. It's the individual's choice which skill you prefer to use. Once all that is left is FT8 and derivatives, what use is any vintage gear without a computer? Progress is good but not if it cuts off history. Last edited by Jon_G4MDC; 22nd Jul 2021 at 11:28 pm. |
23rd Jul 2021, 12:49 am | #11 |
Nonode
Join Date: Oct 2010
Location: Tintinara, South Australia, Australia
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Re: What is QRP?
And digital modes are mostly not 'conversational', very much in the 'you're 5 9 - next operator please' style of short, sharp contact.
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23rd Jul 2021, 8:31 am | #12 |
Nonode
Join Date: Mar 2010
Location: Dukinfield, Cheshire, UK.
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Re: What is QRP?
Maybe drifting OT, but several years ago (before the QRM - oops, 'man-made interference' - got so bad) we did a little experiment on our 160m net. We normally ran about 10w PEP, which was more than enough, but we decided to reduce our powers to see just how well we could hear each other at real QRP levels.
We all got down to ~50mW before readability began to suffer badly. We couldn't do that now. One of our net members lives quite close to a new tram line and has a huge noise level. Any significant reduction from my normal 10w and he loses me in the hash. This was AM btw.
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23rd Jul 2021, 12:44 pm | #13 |
Dekatron
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Re: What is QRP?
Does Q stand for "Question" ? if not then why was Q chosen as the first letter of the codes.
David |
23rd Jul 2021, 12:49 pm | #14 | |
Dekatron
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Location: Oxford, UK.
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Re: What is QRP
Quote:
Craig |
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23rd Jul 2021, 12:55 pm | #15 |
Dekatron
Join Date: Apr 2019
Location: Worthing, West Sussex, UK.
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Re: What is QRP?
CW I assume is Continuous Wave but in simple terms what is it in terms of radio reception/transmission operation ?
David |
23rd Jul 2021, 12:57 pm | #16 |
Dekatron
Join Date: Apr 2011
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Re: What is QRP?
Q....When I was leaning Morse at Alf's Academy it was always God Save The Queen...
dah dah di(t) dah. Lawrence. |
23rd Jul 2021, 1:08 pm | #17 |
Octode
Join Date: Jun 2004
Location: Reading/Fakenham, UK.
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Re: What is QRP?
There are at least 150 Q-codes. They were used for professional Morse communications (merchant marine and aviation for example) to reduce time to send a message and of course is not language dependent. Now only a dozen or so are used by radio amateurs in Morse code contacts. They are occasionally used in amateur voice communication, but this is unnecessary unless the signals is weak or the other station does not have English as a first language.
Q has nothing to do with 'question' - AFAIK! Low power (QRP) communications by radio amateurs is probably where the majority of home construction now resides. There are plenty of QRP kits, to assemble yourself now - probably more than ever! The UK G-QRP Club issues a quarterly magazine with lots of constructional articles. Membership is £6 per annum and hasn't gone up for at least a decade! In amateur circles, QRP generally refers to a carrier power of 5 watts or less. For anyone interested, there's more than you ever wanted to know about the Q (not QR!) code on the internet. 73 (not a Q-code, but an ancient telegraphy abbreviation for 'best wishes'!) Ian |
23rd Jul 2021, 1:18 pm | #18 |
Dekatron
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Re: What is QRP?
It's a bit of a misleading name actually, since when sending morse the wave is not at all continuous, but normally off, and switched on only for short and long periods to signify dots and dashes.
At the receiver end the mere presence or absence of the signal would be quite difficult to hear, so a receiver in CW reception mode usually mixes the incoming signal with another 'local' RF signal - often known as a BFO or Beat Frequency Oscillator - whose frequency is just an audio frequency different from that of the incoming signal. Mixing these two signals together produces an audio tone whenever the distant transmitter is sending a signal, and no tone when it is not. The injection of the local 'near' RF frequency to create a tone may take place in the I.F stage rather than the RF stage. Morse can also be sent as audio tones using audio modulating modes such as FM and AM and received in the normal way for those modes, but then this is not CW, even though the carrier IS actually on all the time during transmit on those modes. |
23rd Jul 2021, 1:25 pm | #19 |
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Re: What is QRP?
There is even a Q code for 'Please shine a searchlight on the underside of a cloud in the hope that I can see it and work out where the aerodrome is' This one is at the more desperate end of the Q code spectrum
But meanings have become distorted over the years. QSL is 'Please confirm contact'. It doesn't necessarily have to involve postage stamps and pre-printed cards. David
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23rd Jul 2021, 1:52 pm | #20 | |
Dekatron
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Re: What is QRP?
Quote:
Dah Dah Dit Dit Dit... Dit Dit Dit Dah Dah |
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