I think you only need the rf amp above 20 meters. My homebrew receivers have no rf amp before the mixer and hear better then the R390a I had did.
Now if you want good performance on 15 and 10 meters, you likely need an rf amp, or maybe if you use really crappy antenna's, but on a good antenna, you get much more signal then even the old gear needs. Brett N2DTS ----- Original Message ----- From: "Jim Miller WB5OXQ in Waco" <[EMAIL PROTECTED]> To: "Discussion of AM Radio in the Amateur Service" <[email protected]> Sent: Sunday, February 17, 2008 8:19 PM Subject: Re: [AMRadio] Wanted: Receiver - New England > Watch out for some of the very old receivers that don't have a very good > front end and are not very sensitive. I would try to look at specs and find > a receiver that has at least 1 microvolt sensitivity. Stay away from the > smaller rigs that do not have an rf amplifier and some don't. always check > the tube lineup to make sure. Some even have 2 rf amp tubes. I have owned > rigs like the NC183s that have push pull audio out and others like an NC98 > that had only a 6aq5 making a watt but sounded real good and rich connected > to the correct speaker and the speaker has a lot to-do with how good the > audio sounds. I use a 2 way speaker that came from a tube type Zenith > stereo radio. It has a 8" woofer and a 2" tweeter and was built to be used > on a radio that only made 1.5 watts of audio so it drives easily with single > ended output radios and sounds very full and rich. If you love rich tone > stay away from small speakers that have small drivers in them but be aware > that if you use a large system built for a home stereo system it may need > more power than many radios can put out. > Here is a good web site that may have useful information for you. > http://www.dxing.com/swrx.htm > > ----- Original Message ----- > From: "JT Croteau" <[EMAIL PROTECTED]> > To: "Discussion of AM Radio in the Amateur Service" > <[email protected]> > Sent: Sunday, February 17, 2008 6:58 PM > Subject: Re: [AMRadio] Wanted: Receiver - New England > > > >I want to thank everyone who has responded so far, both on and off > > list, to this thread. Brett, N2DTS, said, a couple posts posts back, > > that I need to take a better inventory of my priorities so let me try > > and clarify what they are to me. > > > >>From what I've read, there are two categories of receivers; > > "Battle-Fields" and Hi-Fidelity and it is very difficult to have your > > cake and eat it to. Unfortunately, I am trying to have a mixture of > > both but leaning more towards Hi-Fi because it is the pure love of the > > sound of AM that is driving me to setup this AM station. > > > > I am learning that there is no perfect receiver and it is very hard > > for a newbie like me to pick one. I wish I had the luxury to afford > > to buy several different ones like some people but I can only afford > > one receiver at the moment A big problem for newbies is the fact > > that EVERYONE has differing opinions for each model and it's often > > hard to get two people to totally agree on the same model. For > > example, I'll ask for opinions on an ABC-123 and one person will > > reply, "oh yeah, it's awesome on AM" while another will say "stay > > away, it's only good for slopbucket signals". If I could afford > > multiple purchases, it'd be much easier to take a gamble and > > experiment but I can't so it's very difficult to choose from just > > looking at specs and "opinions". > > > > With this said: > > > > AM 75M and 40M coverage is my primary interest at this time, I will > > NEVER be using the radio to tune in slopbucket nor CWer. SWL and 160M > > coverage would be nice as well but it will be a couple years before I > > have space for a 160M antenna. > > > > Hi-Fidelity is near the top of my must haves but not if it's > > results in a huge hit on receiver performance. However, I definitely > > don't want bottom of the barrel communications grade audio. I've been > > in some shacks where the audio fills the room and you can feel the > > audio down to your bones. I want to achieve this or as close as I can > > get within my budget. > > > > Looks, style, size, and weight don't really matter as it's what's > > inside the box that counts to me. Ideally the smaller the better and > > if it fits in a standard 19" rack, all the better as I have plenty of > > rack space. > > > > Budget - Yeah, this will always be an issue for me. But I can > > realistically afford to spend a max. of $400 on a receiver so I may > > not be able to get super Hi-Fi with this budget but I would think that > > I should be able to still find something with very good fidelity. If > > I had the money to go all out, I'm the type of person who definitely > > would so I am not trying to cheap out on this. But I do want to get > > something now rather than save an wait.. patience and me have never > > gotten along. > > > > Since my first post a couple days ago, I've been reading a bit about > > Hallicrafters SX-17's and SX-42's with their push-pull 6V6's and how > > they can really make some very nice audio - a couple people seem to > > really like these. However, for some reason, these two rigs don't > > seem to be mentioned much.. are they genuine "sleepers" in this case? > > The SX-17 appears to have good sensitivity and good selectivity with > > an IF bandwidth switch actually works. I think I read that the narrow > > position is somewhere around 4-5 kc and the wide is somewhere around > > 10-12 kc. > > > > Has anything I've said made sense and may point me to more specific > > models of receivers I should be looking at? > > > > Thanks again. > > > > -- > > JT Croteau, N1ESE - Manchester, NH (FN42gx) > > Contest Manager, TARA Skirmish > > ______________________________________________________________ > > Our Main Website: http://www.amfone.net > > AMRadio mailing list > > Searchable Archives: http://www.mail-archive.com/[email protected]/ > > List Rules (must read!): http://w5ami.net/amradiofaq.html > > List Home: http://mailman.qth.net/mailman/listinfo/amradio > > Help: http://mailman.qth.net/mmfaq.html > > Post: mailto:[email protected] > > To unsubscribe, send an email to [EMAIL PROTECTED] with > > the word unsubscribe in the message body. > > > > > > ______________________________________________________________ > Our Main Website: http://www.amfone.net > AMRadio mailing list > Searchable Archives: http://www.mail-archive.com/[email protected]/ > List Rules (must read!): http://w5ami.net/amradiofaq.html > List Home: http://mailman.qth.net/mailman/listinfo/amradio > Help: http://mailman.qth.net/mmfaq.html > Post: mailto:[email protected] > To unsubscribe, send an email to [EMAIL PROTECTED] with > the word unsubscribe in the message body. ______________________________________________________________ Our Main Website: http://www.amfone.net AMRadio mailing list Searchable Archives: http://www.mail-archive.com/[email protected]/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:[email protected] To unsubscribe, send an email to [EMAIL PROTECTED] with the word unsubscribe in the message body.
