Warning: Creating default object from empty value in /homepages/11/d132647312/htdocs/Amfone/mkportal/include/SMF/smf_out.php on line 47
Good receiver for AM on Ham Bands?




 
The AM Forum
October 01, 2023, 05:31:57 PM *
Welcome, Guest. Please login or register.

Login with username, password and session length
 
   Home   Help Calendar Links Staff List Gallery Login Register  
Pages: 1 ... 3 [4]   Go Down
  Print  
Author Topic: Good receiver for AM on Ham Bands?  (Read 61189 times)
0 Members and 1 Guest are viewing this topic.
K5UJ
Contributing
Member
*
Offline Offline

Posts: 2845



WWW
« Reply #75 on: December 05, 2011, 08:45:01 PM »

I put on cans only if it makes the difference between copy and no copy.

I prefer speakers, but I am in comfortable range of at least a dozen big signals from the western Great Lakes region and down south and over to Missouri and Iowa.  Nothing like a big carrier and big audio.  crank up the volume and enjoy. 
Logged

"Not taking crap or giving it is a pretty good lifestyle."--Frank
k4kyv
Contributing Member
Don
Member

Offline Offline

Posts: 10062



« Reply #76 on: December 05, 2011, 09:50:40 PM »

Here is some useful info on post-WWII receivers, including descriptions and photos.

http://www.radioblvd.com/Post-WWII%20Ham%20Gear.htm


Click here for a guide to the entire website
Logged

Don, K4KYV                                       AMI#5
Licensed since 1959 and not happy to be back on AM...    Never got off AM in the first place.

- - -
This message was typed using the DVORAK keyboard layout.
http://www.mwbrooks.com/dvorak
N1KK
Member

Offline Offline

Posts: 26


« Reply #77 on: December 06, 2011, 07:00:49 AM »

Hello John

I was reading your description,
"It has an SME antenna input, a USB port, and an audio line out."
What is the audio line out for if you need a sound card for the audio?

Ken
N1KK




Ken,

I restore old tube receivers for a living. I have a Collins 74A-2a on the bench right now along with a Hallicrafters HT-37 transmitter, and a Collins R390a in waiting. I know most of the radios mentioned here inside and out. I'm listening on an SP-600 and an HQ110a right now.

What I will tell you is the SDR is probably the best fidelity option out of the lot. Now Dave, W2VW has his SDR's mixed up. The one I referred to is the Soft66LC2, which is not a "Softrock", but instead a complete receiver with its own front end. You do not have to use another radio's I.F. stage.

Here's and image of the board for this SDR which comes full assembled and tested. It comes with a little case that you have to cut some holes in for the connectors and LED.


It has an SME antenna input, a USB port, and an audio line out. It is powered by the USB port (FYI: It doesn't seem to have the ground loop problems or RF hash problems reported on other SDR's using USB). All you need is a decent stereo audio card and you can have whatever bandwidth filters you want 22k, 6k, 9k, 25k 41k ... it just depends on the sampling rate of your sound card and its driver. I use the M-Audio Delta 44 which works amazingly well at $150. But you can use the built in soundcards as well.

Here's and image of the board in the case (less front cover). Behind it you can see the bottom part of the software, in this case its the WinRad software.


Here's a link to a YouTube video of it working. Mind you its a Japanese Ham, but you can see how it works here. The radio in the video is the version just before the 66LC2, called the 66ADD. The Soft66LC2 is the current model. Here's the link:



You can use WinRad software to control this and it is simple to use. You get a visual display of the band. and you can see the spectral display of the signal your listening to on that. I believe there is a way to use the Flexradio (PowerSDR) software but I haven't figured that out yet on this SDR. (BTW, Has anyone tried that yet with this SDR?)

You can purchase it directly from Kazunori Miura, JA7TDO at his website via PayPal. The fully assembled unit which requires only the holes in the case is $118 including shipping. The link to his site is http://zao.jp/radio/order/#soft66ad

As far as how it sounds relative to a old tube radio, its much clearer. And since you can see the signal, you can contour the filters to match the signal your trying to receive. And you can use Synchronous Detection to help reduce fades. It's really cool. It's just not Vintage!

John, W2WDX
Logged
W2WDX
Guest
« Reply #78 on: December 13, 2011, 04:21:50 PM »

Hi Again,

Let me first say, I'm not a fan of the Collins S-line for AM use. Collins by this time really got a SSB bias (as did many manufacturers of this period). However they are very nice for SSB.

On the Soft66, let me simplify this a bit. The audio out is to drive the software used to process the audio. There is a proprietary method used by these SDR's to process the audio called I&Q.

The audio out on the card is not meant to be for listening (while you could), it's meant to feed the software. So do not think of this output on the card as a line output or speaker output, as in a normal receiver. It is meant to be sent to software for further processing, so as to be listenable.

There is much material online about the process, so read that. (I won't bore everyone here going over this.) Suffice it to say, the specific type of audio goes into the audio card on your computer and the software processes the signal into a usable analog audio signal you can listen to. It is a broadband signal fed into the software, and it can then be manipulated and viewed as a bandpass (depending on your cards max sample rate). The software does the filtering, spectrum display, equalization, and most of the functions that allow you to tune in the signal. This is an over simplification, but gives you the idea of whats going on.

Read information on the FlexRadio site, WinRadio or anything regarding SDR receivers online and this will give you all the technicals on what's going on with I&Q and SDR in general.


John, W2WDX
 
Logged
K3ZS
Member

Offline Offline

Posts: 1037



« Reply #79 on: December 14, 2011, 10:59:03 AM »

I & Q signal processing is old hat technology, used for decades in Doppler radar, phased array radar, digital cellphones and military communications.   It is not something new that ham radio has been created for ham radio.
Logged
K3ZS
Member

Offline Offline

Posts: 1037



« Reply #80 on: December 14, 2011, 11:02:44 AM »

And also todays digital TV, both on the air and cable.
Logged
w3jn
Johnny Novice
Administrator
Member

Offline Offline

Posts: 4620



« Reply #81 on: December 14, 2011, 11:54:08 AM »

I/Q processing in ham radio receivign is as old as the GE YRS-1 DSB sync detector circa 1952, and probably older.  ANy phasing SSB xmitter also obviously does I/Q processing to reject the unwanted sideband.
Logged

FCC:  "The record is devoid of a demonstrated nexus between Morse code proficiency and on-the-air conduct."
KM1H
Contributing
Member
*
Offline Offline

Posts: 3519



« Reply #82 on: December 14, 2011, 11:56:32 AM »

Bell Labs was doing it before WW2
Logged
Todd, KA1KAQ
Administrator
Member

Offline Offline

Posts: 4305


AMbassador


« Reply #83 on: December 14, 2011, 02:47:28 PM »

Let me first say, I'm not a fan of the Collins S-line for AM use. Collins by this time really got a SSB bias (as did many manufacturers of this period). However they are very nice for SSB.

No bias involved, Collins focused on communications gear, not entertainment receivers. As did others. High fidelity wasn't a consideration for most folks using AM. Punchy audio was more valued to cut through the heterodynes and other noise on the bands. In fact, about midway through production of the KW-1 Collins changed the values of numerous components to restrict the audio further, just for this reason.

Many of us prefer the older sets that provide higher fidelity for AM use these days, because it's great to enjoy when you can. In the case of older tube receivers, push-pull output really does the job. Coupled with a speaker capable of covering the spectrum of frequencies, something like and early Super Pro where you can open up the IF to 16 kc on a quiet night with big signals is a thing of beauty.

On the noisy nights, I can't imagine trying to operate without the utility of the 75A-4 with its steep skirts and its passband tuning. Especially when a station cozies up next to your QSO. The trade off is - the audio leaves a lot to be desired at 6 kc as well as other limitations. As Steve points out, at narrower bandwidths, the speaker you choose matters less since it doesn't need to be HiFi. The aging process tends to take away some high frequency ability too.

I think the last P-P output tube receiver was the SX-62B, beating the HRO-60 by about a year. But the HRO-60 offers far more utility and performance for amateur use, and was probably the top of the heap for development, making it tough to beat if you can only have one receiver (and don't want to bother with external audio amps) with the best available technology of the day.

Logged

known as The Voice of Vermont in a previous life
N1KK
Member

Offline Offline

Posts: 26


« Reply #84 on: December 16, 2011, 06:57:33 AM »

How does the Collins 75S-1 compare to some of the others mentioned
here?  As mentioned, I have one of these and if its just as good
as the HQ-170 or NC-300/303, or some of the others, then my search
has ended.  Playing with this receiver it seems OK but not what I seem
to remember my HQ-170 was in sensitivity.  I can't remember the audio
of the HQ-170A I had even through I did use it with a Johnson Ranger
back in the 60's in AM mode

Ken
Logged
W2WDX
Guest
« Reply #85 on: December 16, 2011, 01:53:00 PM »

I & Q signal processing is old hat technology, used for decades in Doppler radar, phased array radar, digital cellphones and military communications.   It is not something new that ham radio has been created for ham radio.


Most of us know it's not new. Did I imply that? What I did say was I wasn't going to make a long description as to what it was, since many have known about for a very long time.
Logged
K3ZS
Member

Offline Offline

Posts: 1037



« Reply #86 on: December 16, 2011, 05:06:45 PM »

Sorry if my reply sounded contentious.   I was just wondering if the SDR receiver manufacturers were making it sound like they invented complex signal processing.  It is much easier in software than all the circuitry required for the hardwired methods of the past.
Logged
KM1H
Contributing
Member
*
Offline Offline

Posts: 3519



« Reply #87 on: December 16, 2011, 09:43:12 PM »

Quote
I think the last P-P output tube receiver was the SX-62B, beating the HRO-60 by about a year. But the HRO-60 offers far more utility and performance for amateur use, and was probably the top of the heap for development, making it tough to beat if you can only have one receiver (and don't want to bother with external audio amps) with the best available technology of the day.


BUT the HRO-60 was in production as late as 1968, thats a pretty long life having started in 52.

Who was the first ham/comm set with PP outputs? National and Hammarlund both had it in 36 but consumer sets such as Scott had it in 31 in the AW-12 for example.
Logged
N4BBQ
Member

Offline Offline

Posts: 7



« Reply #88 on: January 06, 2012, 02:52:23 PM »

I'm fairly new to the board here but have been licensed a while, anywayz, I'm just getting interested in playing around with AM. I don't have any of the receivers you all have mentioned, but here's what I plan to use to receive AM.

I plan to use an Empire (Singer) NF-105 for my receiver. I'm going to mod the tuning unit and add one or two 6kc@455kc crystal filters and I've built three separate (160/80/40) bandpass filters to feed the antenna into before going into the front end. I figger that'll make an ok receiver.

Have I missed anything?
Logged
Steve - K4HX
Guest
« Reply #89 on: January 06, 2012, 08:40:49 PM »

You'll have one of the more unique receivers on the bands. I used one of those very briefly about 28 years ago. I have no idea on the internals. I also used some of the old Empire antennas (loops and rods) too. These had the brown/tan crinkle finish. Cool stuff.
Logged
N4BBQ
Member

Offline Offline

Posts: 7



« Reply #90 on: January 06, 2012, 10:04:23 PM »

You'll have one of the more unique receivers on the bands. I used one of those very briefly about 28 years ago. I have no idea on the internals. I also used some of the old Empire antennas (loops and rods) too. These had the brown/tan crinkle finish. Cool stuff.

Very good. There's no real AGC in this thing so building that would be nice as well and I could convert the meter to a real S meter, but that'll be later on. I have two of these with most of the plug ins. Pretty cool stuff.
Logged
kb3rdt
Member

Offline Offline

Posts: 249


poop cup


« Reply #91 on: January 08, 2012, 08:37:34 PM »

Hello I just picked up a Hammerlund SP-600 JX for $350.00 I didn't get it for looks but works I was like wow! smooth thanks Guys for the idea!


* Hammerlund SP-600 JX.JPG (2547.97 KB, 4288x2416 - viewed 816 times.)
Logged
Pages: 1 ... 3 [4]   Go Up
  Print  
 
Jump to:  

AMfone - Dedicated to Amplitude Modulation on the Amateur Radio Bands
 AMfone 2001-2015
Powered by SMF 1.1.21 | SMF © 2015, Simple Machines
Page created in 0.086 seconds with 18 queries.