Geoff Burginon wrote:
Which particular one of Collins receivers? What was the actual specified noise floor in figures? Frankly, I doubt you can get much lower than the WinRadio G313i -138 dBm. Read also this: "If I had to choose between a Collins 95S-1 and the WR-G303i (ignoring the obvious fact that the 95S-1 tunes to 2 GHz), I would take the WR-G303i." John Wilson, ShortWave Magazine (more details on http://www.winradio.com/pdf/g303i-review-swm.pdf ) And this in fact refers to the *predecessor" of the WR-G313i, which is a much better radio still - 5 stars by WRTH. My WR-G313i does indeed have the advertized -138dBm noise floor, and even the S-meter reliably measures down to that level - with 1dB accuracy. Not speaking of the ultra-sharp continuously variable IF filters down to 1Hz bandwith. Now *that's* what I'd call winning the contest hands down. ;-) Geoff Geoff: -143 dB was the noise floor of the R-390A, according to web info. Otherwise, of course, it was an old tube (32 of them!) boatanchor with mechanical tuning, weighed a ton, and had none of the amenities that modern digital radios provide. But it WAS quiet! -- Brian Denley http://home.comcast.net/~b.denley/index.html |
On Wed, 2 Feb 2005 23:46:12 -0500, "Brian Denley"
wrote: My WR-G313i does indeed have the advertized -138dBm noise floor, and even the S-meter reliably measures down to that level - with 1dB accuracy. Not speaking of the ultra-sharp continuously variable IF filters down to 1Hz bandwith. Now *that's* what I'd call winning the contest hands down. ;-) Geoff Geoff: -143 dB was the noise floor of the R-390A, according to web info. Otherwise, of course, it was an old tube (32 of them!) boatanchor with mechanical tuning, weighed a ton, and had none of the amenities that modern digital radios provide. But it WAS quiet! -- Brian Denley http://home.comcast.net/~b.denley/index.html Thanks for the info Brian, sounds indeed awesome, I think I'd love to own this radio (and I thought I had no space left! :-). But frankly, I am still a bit confused about the noise floor. Yes I did see the Web pages which mention -143 dBm and one even says -147dBm, but some other pages specify less, for example -127 dBm, which seems to me more realistic, considering the sensitivity specs, which appear to be poorer than my WR-G313i (I have verified its sensitivity with a good signal generator, and it is actually about 2-3 dB better than specified): R-390A specs: http://members.aol.com/tcsopr/r390a.htm WR-G313i specs: http://www.winradio.com/home/g313i-s.htm How could a receiver with a higher noise floor have a better sensitivity? See also the original military specs on: http://209.35.120.129/mil-r-13947b.pdf and this table http://www.sherweng.com/table.html which shows the noise floor as -137dBm, i.e. about the same as the WR-G313i. Confusing, eh? I also note the dynamic range of the R-390A is rather poor: according to the specs on http://members.aol.com/tcsopr/r390a.htm it is only 52.7 dB (but this can't possibly be correct?), and on http://www.sherweng.com/table.html it is more reasonable 79dB (or 81dB wide-spaced), but it is still nothing compared to the 95 dB of my WR-G313i... Geoff |
Id say the Lowe is quiet, but you forgot to power it up!
B "Brian Hill" wrote in message ... "Brian Denley" wrote in message ... Brian Hill wrote: "Geoff Burginon" wrote in message news:41fe2980.12117500@news-server... On 30 Jan 2005 19:37:29 -0800, wrote: I started thinking about this tonight. I was tuning around with a Lowe HF-150, comparing it with some other receivers, and was struck by how quiet the 150 is--and by what an advantage this is when it comes to resolving weak AM signals. So, just out of curiosity, what's the quietest receiver you've used and/or owned? The WinRadio G313i by far. Noise floor -138 dBm and the continuously adjustable IF filter let's you adjust the IF bandwidth to precisely match the bandwidth of the signal. No other receiver comes close. Geoff R-390 B.H. The Collins should win this contest hands down. Nothing, to my knowledge, ever had a lower noise floor. The story is that it was only limited by the Galactic background noise level. You can't do any better than that. -- Brian Denley http://home.comcast.net/~b.denley/index.html They're pretty amazing receivers. Now if they only tuned like a SP-600 ;) B.H. |
All times are GMT +1. The time now is 07:30 AM. |
Powered by vBulletin® Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
RadioBanter.com