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  #161 (permalink)  
Old 03-03-2013, 8:29 PM
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"Did a video of 10 meters today. Not a place I check out often and my antenna is probably no good there. I gave it a shot however:
CR-1 vs R75 daytime 10 meters - YouTube" CR-1 vs R75 daytime 10 meters - YouTube

That Costa Rican DX contest station sounds louder on the the R75 despite barely moving its S-meter. However that station registers a steady S9 on the CR-1. Something's amiss with the CR-1 meter.

Seems the CR-1 always shows high meter readings, even without hearing a station, right? Ambient QRN level on 28 megs should probably be about S1-S2 most of the time. Maybe less on a poor antenna.

Thanks for the video.
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  #162 (permalink)  
Old 03-03-2013, 11:26 PM
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I scanned through the lower band of MW (with the scan button). I will say, the CR-1 is ok on MW, however the R75 is much better. I have done a fair bit of DX in the MW band. The CR-1 would not be my top pick in this area.

The video has no explanations or whatnot. I feel the video speaks for itself. You don't here the tough pileups or much of anything for that matter. Although my local 680 booms in as expected.

Commradio CR-1 MWDX test below 1000KHz - YouTube
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  #163 (permalink)  
Old 03-04-2013, 1:02 AM
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Corbintechboy, what sort of antenna is connected to the CR-1 on your MW video? There seems to be a slight buzzing (fluorescent lights?) that might benefit from a noise blanker.

I presume that video was recorded in the evening. The 540 to 1000 KHz range should be full of broadcast stations every 10 kHz. What I'm hearing isn't that impressive. Other than your local station few stations are really "armchair copy."

Notice that your local station on 680 KHz can also be barely heard on 670 and especially on 690. I believe that station in Corbin runs less than one KW but I have no idea how close you are to the antenna.
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  #164 (permalink)  
Old 03-04-2013, 2:07 AM
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Quote:
Originally Posted by corbintechboy View Post
I scanned through the lower band of MW (with the scan button). I will say, the CR-1 is ok on MW, however the R75 is much better. I have done a fair bit of DX in the MW band. The CR-1 would not be my top pick in this area.

The video has no explanations or whatnot. I feel the video speaks for itself. You don't here the tough pileups or much of anything for that matter. Although my local 680 booms in as expected.

Commradio CR-1 MWDX test below 1000KHz - YouTube
Sounds like a lot of RFI in that range.
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  #165 (permalink)  
Old 03-04-2013, 6:27 AM
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Originally Posted by nickcarr View Post
Sounds like a lot of RFI in that range.
Never really an issue in that area. I will do some comparisons with the R75 tonight and get a video out.
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  #166 (permalink)  
Old 03-04-2013, 10:21 AM
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I would make sure that any other devices such as cable boxes and flat-screen TVs are turned off.
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  #167 (permalink)  
Old 03-04-2013, 10:45 AM
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Thanks for doing the comparisons CTB. I might be off base here but don't you need to put preamp 1 on the R75? My R8500 ran at full RF gain so signals (s-meter) were always stronger on it with the preamp off on the R75. Is the CR-1 running full gain?
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  #168 (permalink)  
Old 03-04-2013, 12:42 PM
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Originally Posted by corbintechboy View Post
Never really an issue in that area. I will do some comparisons with the R75 tonight and get a video out.
In the MW video there's clearly some powerline noise there. What are you using for a power source -- the internal battery?
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  #169 (permalink)  
Old 03-04-2013, 12:44 PM
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Quote:
Originally Posted by woody_46 View Post
Thanks for doing the comparisons CTB. I might be off base here but don't you need to put preamp 1 on the R75? My R8500 ran at full RF gain so signals (s-meter) were always stronger on it with the preamp off on the R75. Is the CR-1 running full gain?
Heck, I had my R75 on PREAMP 2 for about 99.9% of its entire life.
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  #170 (permalink)  
Old 03-04-2013, 1:06 PM
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Quote:
Originally Posted by nickcarr View Post
Heck, I had my R75 on PREAMP 2 for about 99.9% of its entire life.
I just figured the CR-1 was running at full gain. If the R75 wasn't that's why the discrepancy in S meter readings between the two. I noticed in the videos the preamp wasn't on for the R75. I only got an accurate S meter reading with preamp 1 on with my R75. Sensitivity measurements in the manual also show it with the preamp on.
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  #171 (permalink)  
Old 03-04-2013, 4:26 PM
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Anyone else receive a radio or confirmation as shipped? My order shows as shipped but no tracking number (yet).
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  #172 (permalink)  
Old 03-04-2013, 4:31 PM
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Originally Posted by NRD-505 View Post
Anyone else receive a radio or confirmation as shipped? My order shows as shipped but no tracking number (yet).

Same here in S.Florida.
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  #173 (permalink)  
Old 03-04-2013, 5:05 PM
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I've confirmed, the S-Meter reading is a minor software bug that should be corrected within a short while. My best advice- ignore it for the time being. The S/W team is aware of it and does have plans to make it go away. Let's hear it for downloading firmware upgrades! Did everybody order their CR-1 with the internal battery? When you unplug your external power source, a small D-Cell looking battery outline appears which tends to indicate battery status. Pretty cool to have this much performance in a field portable radio.
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  #174 (permalink)  
Old 03-04-2013, 5:11 PM
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Originally Posted by NRD-505 View Post
Anyone else receive a radio or confirmation as shipped? My order shows as shipped but no tracking number (yet).
Nope, there is no tracking number shown. Hopefully, my CR-1 will be here in the next hour or so...
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  #175 (permalink)  
Old 03-04-2013, 6:33 PM
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Default I am thinking of getting one

Hi guys , I am thinking of getting a cr 1 . I am just crazy about some of the user interface ideas used . I like the small size as well . I was holding offf because the uhf band quit at 468 which as you guys know knocks out a lot of police,fire listening. Has anyone heard if they plan on extending the 400 mhz band to include the public service stuff ? I am concerned as well of the rx ability Hopefully they will address these issues soon .I think this radio is to cool to not keep an eye on . I am not even a dedicated or experienced SWL like most of you guys just a ham kb2huk who likes to have the ability to hear it all . John Molenda
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  #176 (permalink)  
Old 03-04-2013, 8:37 PM
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Ok, I did some tests.

The CR-1 is very sensitive even in the MW band. If using the speaker alone you would not get that impression. The reason seems to be gain in the form of volume. The channel is indeed there on headphones, out of the speaker it is so faint you cannot or barely hear it.

I also noticed a type of noise below 600KHz that is not present on the R75 (the noise from the video). I cannot figure this out. Without the antenna the noise is not there so who really knows.

All in all I am impressed with the radio. It picks up really well and I am very confident that this little gem will age like fine wine. The developer is responsive and eager to make this radio the best it can be. It is worth every penny and I believe we will get more then we paid for in the form of usability and portability and the added updates are a perk that will be well received. Great radio built like a tank.
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  #177 (permalink)  
Old 03-04-2013, 11:34 PM
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Glad to read the update corbintechboy! I should be getting the receiver tomorrow afternoon.
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  #178 (permalink)  
Old 03-05-2013, 10:32 AM
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Hey CTB, I enjoyed your video's, thanks for sharing your findings.

Could the noise you mentioned be caused by the R75? I notice noise from mine.

How would you compare the CR-1 to the E1?

Thanks
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  #179 (permalink)  
Old 03-05-2013, 11:17 AM
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Quote:
Originally Posted by corbintechboy View Post
Ok, I did some tests.

<snip>
I also noticed a type of noise below 600KHz that is not present on the R75 (the noise from the video). I cannot figure this out. Without the antenna the noise is not there so who really knows.
</snip>
There is a possibility that a very strong MWBCer (maybe close to you?) either in or around 600 khz is getting in here, since the noise isn't there with the antenna off. That would pretty much eliminate circuit anomolies. Another possibility is a nearby appliance. It's hard to say for sure...Mike
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  #180 (permalink)  
Old 03-05-2013, 11:55 AM
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"There is a possibility that a very strong MWBCer (maybe close to you?) either in or around 600 khz is getting in here,"


Precisely,, but that isn't a good sign for the CR-1. There's no powerful AM station for many miles. From what I can tell, that station on 680 KHz is WCTT in Corbin KY running less that a KW. Corbin is in the middle of no where. RF boondocks. A reception paradise!

How would the CR-1 do in a major city surrounded by 5-10 KW broadcasters and maybe a Clear Channel 50 KW station or two? How does it work down to VLF listening to 25 watt NDBs or hams on 473 KHz running a few watts EIRP? Flex radios can't pull that off without outboard help!

The CR-1 attempts to do something that is very difficult to do: UHF, VHF, VLF and ham bands... all in one itty bitty cutesy package.
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