IBOC and ssb or sync detection


lrdheat
 

I had a question concerning IBOC and sync: A strong signal (at least at my QTH in Laredo, TX) from an IBOC station (KRLD Dallas 1080 KHz) creates quite a bit of hash on 1070 and 1090. When using my Grundig G3 on 1070 (KNX Los Angeles), I was expecting to have less hash on the lower sideband or lower sideband sync than on the upper sideband (or upper sideband sync. Surprisingly (to me), the signal from 1070 was cleaner on upper sideband! When I checked for reception of a station on 1090, the LOWER sideband was cleaner! Why would this be?
 
An unrelated question or 2...The G3 holds sync, even on weak signals on upper sideband. On lower sideband, the set loses sync more easily (on weak signals). In the few days that I have had the set, it seems to be getting better at holding lower sideband sync. Is this possible? Could I be burning the set in and getting better results? I do have some local stations mix into sideband and sync reception...I can defeat this by touching the antenna base, or by deploying the atenuation switch. Could local mixing products result in sync working better on the upper sideband than lower? Sync or ECSS tuning works well on the G3, and makes some weak, beady sounding stations much steadier and stronger.
 
On mw, the set is sensitive (similar to the G5) below about 1100 KHz down into the lw band. With sync or ECSS tuning, stations emerge from nothingness near the upper part of the am range, but is still less sensitive than the G5. Overall, the performance ECSSwise and sync make the G3 a satisfying set.
 
Heatwave


jim_kr1s <jkearman@...>
 

Synchronous and SSB-ECSS detection depend on a locally generated signal at the intermediate frequency (IF). To allow the use of a single bandpass filter at the IF, that locally generated signal (beat-frequency oscillator -- BFO) is shifted in frequency when you toggle from LSB to USB. It's possible the BFO signal in your receiver is not aligned correctly, and also possible it's drifting as the set ages. This correlates with sporadic quality problems sometimes reported with other Grundig models.

73,

Jim, KR1S
http://qrp.kearman.com/ 


lrdheat
 

Thanks, Jim.
 
Is an allignment of the BFO a big job?
 
Heatwave


--- On Thu, 2/18/10, jim_kr1s wrote:

From: jim_kr1s
Subject: [ultralightdx] Re: IBOC and ssb or sync detection
To: ultralightdx@...
Date: Thursday, February 18, 2010, 6:47 AM

 
Synchronous and SSB-ECSS detection depend on a locally generated signal at the intermediate frequency (IF). To allow the use of a single bandpass filter at the IF, that locally generated signal (beat-frequency oscillator -- BFO) is shifted in frequency when you toggle from LSB to USB. It's possible the BFO signal in your receiver is not aligned correctly, and also possible it's drifting as the set ages. This correlates with sporadic quality problems sometimes reported with other Grundig models.

73,

Jim, KR1S
http://qrp.kearman. com/ 


jim_kr1s <jkearman@...>
 



--- In ultralightdx@..., Richard Berler wrote:
>
> Thanks, Jim.
>   
> Is an allignment of the BFO a big job?

Richard,

I saw the reply on ABDX, and that could explain what's happening. I don't know how to align the BFO in that radio. It could be simple or not. When a signal is tuned in accurately in AM mode, something you should be able to do on any strong US station, and the radio is switched to SSB, there should either be no heterodyne, or if there is one, it should be the same pitch on either sideband. If that's the case, the BFO is aligned. The G3 reviews don't give its sync detector high marks, unfortunately. How's its performance compare with traditional ULRs you've used?

73,

Jim, KR1S
http://qrp.kearman.com/ 


Gary Kinsman
 

Hi Richard,

I believe the post on ABDX regarding the IBOC digital sideband layout, and the resulting interference, is correct.

One other thing to keep in mind is that KNX itself is an IBOC station. It's a local for me, but using SSB sync to listen to it results in a lot of digital noise. DSB sync, like that on the Eton E1 series, solves this problem. I believe the E1 is the only portable with DSB sync. I wish Eton would have added this sync mode to the G3 as well.

Regards,
Gary

--- In ultralightdx@..., Richard Berler <lrdheat@...> wrote:

I had a question concerning IBOC and sync: A strong signal (at least at my QTH in Laredo, TX) from an IBOC station (KRLD Dallas 1080 KHz) creates quite a bit of hash on 1070 and 1090. When using my Grundig G3 on 1070 (KNX Los Angeles), I was expecting to have less hash on the lower sideband or lower sideband sync than on the upper sideband (or upper sideband sync. Surprisingly (to me), the signal from 1070 was cleaner on upper sideband! When I checked for reception of a station on 1090, the LOWER sideband was cleaner! Why would this be?
 
Heatwave


Powell
 

The Sony ICF-2010 has DSB sync, but I hear the E-1's is superior. I often get very strong selective fades on WLAC, and with the G3 it gets rather upset on these deep fades. It doesn't bother the 2010 much, but on really bad ones the upper / lower LED switches back and forth. You would think with all the DSP power that can be written into the chips they would have done a better job. Sensitivity on MW and SW need to seriously be improved. Of course I can use one of the tuneable loops on MW to perk things up, but I don't want to HAVE to unless I have to and WLAC is my strongest AM signal at night and on the G3 it's barely OK. At least WLAC and WCKY don't have their IBOC on right now.

Powell in the woods near Silverstreet, SC

--- In ultralightdx@..., "gkinsman1" <gkinsman@...> wrote:

Hi Richard,

I believe the post on ABDX regarding the IBOC digital sideband layout, and the resulting interference, is correct.

One other thing to keep in mind is that KNX itself is an IBOC station. It's a local for me, but using SSB sync to listen to it results in a lot of digital noise. DSB sync, like that on the Eton E1 series, solves this problem. I believe the E1 is the only portable with DSB sync. I wish Eton would have added this sync mode to the G3 as well.

Regards,
Gary


jim_kr1s <jkearman@...>
 



--- In ultralightdx@..., "Powell" wrote:
>
>  You would think with all the DSP power that can be written into the chips they would have done a better job.


I guess they don't think the market is there. I'd like to try an E1. What I've read makes me think you're lucky to get a good one, though.

73,

Jim, KR1S
http://qrp.kearman.com/ 


Gary Kinsman
 

Hi Powell,

Actually the Sony 2010 has SSB sync (USB or LSB), but not DSB sync. I've owned one for about 24 years.

I owned several E1XM units, but never got one that worked totally right.

The best sync detector of my current radios is on my Sat 800, but it doesn't have DSB sync.

Both the E1/E1XM and Sat 800 have better sync detectors than the Sony 2010, but I doubt that these two models will still be working after more than 20 years.

Regards,
Gary

--- In ultralightdx@..., "Powell" <w4opw@...> wrote:

The Sony ICF-2010 has DSB sync, but I hear the E-1's is superior. I often get very strong selective fades on WLAC, and with the G3 it gets rather upset on these deep fades. It doesn't bother the 2010 much, but on really bad ones the upper / lower LED switches back and forth. You would think with all the DSP power that can be written into the chips they would have done a better job. Sensitivity on MW and SW need to seriously be improved. Of course I can use one of the tuneable loops on MW to perk things up, but I don't want to HAVE to unless I have to and WLAC is my strongest AM signal at night and on the G3 it's barely OK. At least WLAC and WCKY don't have their IBOC on right now.

Powell in the woods near Silverstreet, SC


lrdheat
 

I tried an E1...it's sensitivity off of the whip was similar to the G5. I was hoping for a miracle off of the whip (which I'm sure isn't possible to engineer, but hope springs eternal...) Of course, the superior sync modes and 10 Hz ssb increments allowed for superb ECSS listening. Both sidebands sounded identical on the E1. As is the case with my G3, the SONY 7600 GR sounded more natural on the upper sideband, muddier on the lower, although again, not unpleasantly so. On mw, the whip proved ok sensitivitywise, but un-nullabe. In am mode on sw, the G5 is beadier, less steady, weaker on the weaker signals than the G5. On ssb (or sync), the G3 is much closer in (perceived) sensitivity with the G5.
 
On your G3's...do you have local station mixing products when utilizing ssb or sync? I find that I can defeat this by touching the bottom of the antenna as I hold the radio, or by using the attenuation switch. The G5 and SONY 7600 GR did not suffer from this.
 
Heatwave


--- On Thu, 2/18/10, jim_kr1s wrote:

From: jim_kr1s
Subject: [ultralightdx] Re: IBOC and ssb or sync detection
To: ultralightdx@...
Date: Thursday, February 18, 2010, 8:58 PM

 


--- In ultralightdx@ yahoogroups. com, "Powell" wrote:
>
>  You would think with all the DSP power that can be written into the chips they would have done a better job.


I guess they don't think the market is there. I'd like to try an E1. What I've read makes me think you're lucky to get a good one, though.

73,

Jim, KR1S
http://qrp.kearman. com/ 


jaypolicow@snet.net <jaypolicow@...>
 

The 2010 does not have DSB (Dual Sideband) sync...you select either Upper or Lower sideband sync by fine tuning until either the Upper or Lower Led lights up.

Jay Allen

--- In ultralightdx@..., "Powell" <w4opw@...> wrote:

The Sony ICF-2010 has DSB sync, but I hear the E-1's is superior. I often get very strong selective fades on WLAC, and with the G3 it gets rather upset on these deep fades. It doesn't bother the 2010 much, but on really bad ones the upper / lower LED switches back and forth. You would think with all the DSP power that can be written into the chips they would have done a better job. Sensitivity on MW and SW need to seriously be improved. Of course I can use one of the tuneable loops on MW to perk things up, but I don't want to HAVE to unless I have to and WLAC is my strongest AM signal at night and on the G3 it's barely OK. At least WLAC and WCKY don't have their IBOC on right now.

Powell in the woods near Silverstreet, SC


--- In ultralightdx@..., "gkinsman1" <gkinsman@> wrote:

Hi Richard,

I believe the post on ABDX regarding the IBOC digital sideband layout, and the resulting interference, is correct.

One other thing to keep in mind is that KNX itself is an IBOC station. It's a local for me, but using SSB sync to listen to it results in a lot of digital noise. DSB sync, like that on the Eton E1 series, solves this problem. I believe the E1 is the only portable with DSB sync. I wish Eton would have added this sync mode to the G3 as well.

Regards,
Gary


Powell
 

That's strange as there IS sync on mine in  the AM DSB mode. The Sony 7600 has sync also but it's not as good. Sync detection should be standard on ALL radios made that have an AM section!
 
 
Powell 
NNNN
POP email is powell at backroads DOT net



From: gkinsman1
To: ultralightdx@...
Sent: Thu, February 18, 2010 10:32:05 PM
Subject: [ultralightdx] Re: IBOC and ssb or sync detection



Hi Powell,

Actually the Sony 2010 has SSB sync (USB or LSB), but not DSB sync. I've owned one for about 24 years.


Powell
 

Then,  [  on the 2010  ]    when I have, lets say WLAC tuned in and I press sync and there is a severe selective fade, the radio automatically finds the best sideband to switch to.... on super bad strong selective fades I've seen the red LED switch back and forth rapidly. A standard AM radio was totally unlistenable, while the Sony was fine. The G3 does NOT do this and will drop out of sync mode MOST ungracefully.    
 
 
Powell
 
NNNN
POP email is powell at backroads DOT net



From: "jaypolicow@..."
The 2010 does not have DSB (Dual Sideband) sync...you select either Upper or Lower sideband sync by fine tuning until either the Upper or Lower Led lights up.

Jay Allen


Gary Kinsman
 

The 2010 shouldn't "automatically" be selecting the sideband in sync mode. Mine doesn't work this way.

Also, listen to the 2010 in sync mode on an IBOC station, and you'll hear digital "rushing" noise, no matter which sideband is selected. On the E1/E1XM, in DSB sync, this noise is absent.

--- In ultralightdx@..., "Powell E. Way III" <w4opw@...> wrote:

Then,  [  on the 2010  ]    when I have, lets say WLAC tuned in and I press sync and there is a severe selective fade, the radio automatically finds the best sideband to switch to.... on super bad strong selective fades I've seen the red LED switch back and forth rapidly. A standard AM radio was totally unlistenable, while the Sony was fine. The G3 does NOT do this and will drop out of sync mode MOST ungracefully.    
 

Powell
NNNN
POP email is powell at backroads DOT net


Powell
 

That's the way mine works, and if you have the sync on and there is a selective fade with IBOC .... WHOOO boy you get the digital rushing noise that reminds you of a train running through. It's better in narrow, but PFFFT I would rather listen in wide.
 
 
Powell
 
NNNN
POP email is powell at backroads DOT net



From: gkinsman1
The 2010 shouldn't "automatically" be selecting the sideband in sync mode. Mine doesn't work this way.

Also, listen to the 2010 in sync mode on an IBOC station, and you'll hear digital "rushing" noise, no matter which sideband is selected. On the E1/E1XM, in DSB sync, this noise is absent.


Powell
 

I was told the sync on the 2010 will automatically pick which sideband to switch to in a strong selective fade.  That's when I am in regular wide AM and press the sync button.  Until WTAM and KMOX started running IBOC that was  "**THE"** only way WBT was listenable at night and I'm 80 or so air miles from the transmitter. Now, at night 1110 is just   FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF
I am lucky to be close enough  to hear the WBT-FM on 99.3 from Chester, SC .

Powell
 
NNNN
POP email is powell at backroads DOT net