Thanks, Brett for these delightful thoughts on receivers. Very informative.
Dave, W3ST Secretary to the Collins Radio Association Publisher of the Collins Journal www.collinsra.com ----- Original Message ----- From: "Brett Gazdzinski" <[EMAIL PROTECTED]> To: <amradio@mailman.qth.net> Sent: Friday, October 17, 2003 9:02 AM Subject: RE: [AMRadio] FW: Homebrew receiver > Dave, > I always loved the Collins receivers, but they were very poor > for AM work, as I guess you know. > When AM was in, the technology did not seem to support > good filters, xtal filters were in, or low frequency IF > stages, both had drawbacks for hi fidelity AM reception. > When mechanical filters came out, the move to ssb was already > in motion, so Collins concentrated on building a good ssb receiver > for ham use. They were very successful. > > I don't think Collins ever designed a good audio output stage > in anything they built, not like the direct coupled, push pull > output amp like the Scott receivers had, or the hi power > push pull output some of the Hallicrafters receivers used. > > They were not alone, and the best sounding audio receivers were > built at a time when some of them were used as hi fidelity > amplifiers for other things, my Scott has a phono input... > > The Collins receivers could be upgraded easy these days, with an add on > low distortion AM detector, and good filters, into an outboard > audio amp. > Anything that uses a 455Khz IF frequency can be upgraded > quite a bit with the kiwi filters, you can tack on a new detector > without any trouble, and all the Collins receivers were very accurate > in frequency, very stable, with good frequency resolution. > > One of these days, I will get around to upgrading a 75S1 for > hi fidelity AM reception. Those receivers are still quite reasonable > in price, and nice and small. > I had one some time ago, but sold it. > On AM, it was as broad as a barn door, but I did not know about > the kiwi filters then. > > Way back, when receivers like the NC303 were at fests for $50.00, > I don't think you could come up with anything better for AM reception. > Some older radios had better fidelity, but had poor (or no) frequency > resolution, poor bandwidth shape factors, and other problems. > I think only the R390 with outboard audio was in the ball park. > > Its quite surprising that the NC300/303 still sells for a reasonable > price these days....when you see them, they are well under > the cost of something like a 75a4. > Once and a while, I see them for $200.00 or less. > That is a lot of receiver for the price! > > > Brett > N2DTS > > > > -----Original Message----- > > From: [EMAIL PROTECTED] > > [mailto:[EMAIL PROTECTED] Behalf Of David Knepper > > Sent: Friday, October 17, 2003 8:21 AM > > To: amradio@mailman.qth.net > > Subject: Re: [AMRadio] FW: Homebrew receiver > > > > > > Very fine, Brett. In all the receivers that I have at the > > Collins Radio > > Center, I like the NC-303, the best for AM > > > > > > Dave, W3ST > > Secretary to the Collins Radio Association > > Publisher of the Collins Journal > > www.collinsra.com > > _______________________________________________ > AMRadio mailing list > AMRadio@mailman.qth.net > http://mailman.qth.net/mailman/listinfo/amradio
