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Author Topic: 5KC Audio  (Read 47150 times)
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ke7trp
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« Reply #75 on: July 27, 2010, 02:40:20 PM »

Data?  LOL!!!!   How about using them side by side. Screw the data.  I use the one that works better Smiley  Modern SS rigs are made for one purpose.  To go into a pile up, hear one guy and null the rest.  Roofing filters, DSP, twin PBT, auto notch ect.. are all made for that purpose.  In this area the icom is fantastic. However, Its signal to noise ratio, its audio quality and sound cannot compare to the old BW/R390.


C
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Steve - WB3HUZ
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« Reply #76 on: July 27, 2010, 03:09:57 PM »

And this is where DR is important. Audio wasn't part of the discussion.

I completely agree that many old receivers will produce better sounding audio than many newer SS RXs (mostly due to wider bandwidths in the older RXs). I have several old RXs just for this reason (and they look cool too) - some dating back the 1930's. But, I've also used a ton of new SS RXs. And many sound just as good or better than the old tube radios (mostly due to better AGC and detectors).

Blanket statements like "SS RXs can't compare to tube RXs", and "tube RXs sound better than SS RXs"  are not only wrong in many specific cases, as time passes, they are wrong in the general instance too.


Data?  LOL!!!!   How about using them side by side. Screw the data.  I use the one that works better Smiley  Modern SS rigs are made for one purpose.  To go into a pile up, hear one guy and null the rest.  Roofing filters, DSP, twin PBT, auto notch ect.. are all made for that purpose.  In this area the icom is fantastic. However, Its signal to noise ratio, its audio quality and sound cannot compare to the old BW/R390.


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KB2WIG
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« Reply #77 on: July 27, 2010, 03:52:54 PM »

More info on DNR


http://familydoctor.org/online/famdocen/home/pat-advocacy/endoflife/003.html

klc
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k4kyv
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Don
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« Reply #78 on: July 27, 2010, 04:11:33 PM »

I wouldn't say that, some of the old Hy-brid rigs with a li'll interest preformed rather well Smiley
an receive was solid state.

One of the worst examples of that type of receiver was the Yaesu FT-101E series, circa 1978.  The  receiver was double conversion with tunable i.f. somewhat like the 75A-4, but everything was solid state.  The receiver is sensitive enough, but it goes belly up in the presence of a nearby strong signal, even if that signal is at the other end of the band. The old Kenwood T599/R599 pair has similar problems.

Later on, Yaesu went to the FT-300 series which pre-mixed the VFO with the xtal oscillator and used single conversion, for a tremendous improvement.  Then they came out with the FT-901 series that used a PLL configuration instead of simply mixing the oscillators with heterodyne converters.

My friend across town had an FT-301 and he used to be perplexed that I could hear signals on my old pre-WW2 National HRO with the 2.5 volt tubes better than he could with his Yaesu.
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Don, K4KYV                                       AMI#5
Licensed since 1959 and not happy to be back on AM...    Never got off AM in the first place.

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Ed/KB1HYS
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« Reply #79 on: July 27, 2010, 07:12:44 PM »

My kenwood TS-520 hears quite well, but is of course very narrow, listening to one sideband of an AM signal can be useful under certain band conditions, but not really what it was designed for it's definitely optimized for CW and SSB.

 The 390A is FB running an outboard amp to good size speakers, salvaged the amp board from an old home stereo and feed the rectified IF output to it.
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73 de Ed/KB1HYS
Happiness is Hot Tubes, Cold 807's, and warm room filling AM Sound.
 "I've spent three quarters of my life trying to figure out how to do a $50 job for $.50, the rest I spent trying to come up with the $0.50" - D. Gingery
K5UJ
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WWW
« Reply #80 on: July 27, 2010, 08:57:14 PM »

If only we could make a storm QRN eliminator we'd be in good shape this time of year. 
Oh yeah, such a thing exists--it is called the 1 KW carrier.  Unfortunately we're not allowed to use it.

Back to receivers now....
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« Reply #81 on: July 28, 2010, 09:22:07 AM »

I use 4 KW TS-830's as IF's for 6M and up. After a few simple mods, filters, etc, they are pretty much bullet proof and that is with the additional RX gain from the transverters.  In fact they are so hot I bypassed the transverters IF amps in the DEM units as I didnt need the gain to overcome anything.

For years I had a pair of Drake C Lines with lots of mods not mentioned by Sherwood. Its been too long ago to remember the IMD performance but they were excellent under DX contest conditions and Im LOS to many of the top stations in the country. Ive learned to take Sherwoods list with a bit of skepticism as the test setups vary over the years so there is no true correlation. Plus some tests were done by others.

The NCX-3 was a 1960 design with a single high IF and there were probably others even earlier. The NCX-5 has a reputation of being extremely sensitive along with a great AGC and overload handling.

Carl
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W2PFY
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« Reply #82 on: July 28, 2010, 10:16:29 AM »

Quote
ne of the worst examples of that type of receiver was the Yaesu FT-101E

I found that my EE had little sensitivity above 20 meters and had to use a preamp to make it hear.
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