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  #241 (permalink)  
Old 03-08-2013, 2:58 PM
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Hello,

Has anyone else tried receiving VHF/UHF signals, like NWS in the 162 MHz range? I am getting mostly distorted audio. On some signals I get clicking like a geiger counter. HF seems fine.

I checked using a test setup of a discone antenna and passive power divider hooked to a R2500 and the CR-1. CR-1 was using battery power. CR-1 DSP Version is 1592.

HF sensitivity was close between the R2500 and CR-1. HF appears to perform fine.

Code:
VHF R2500 S1 signals were about 50% quieting on the CR-1 with barely detectable audio.
    R2500 S5 signals were full quieting on the CR-1 with very low audio level and distorted audio.
    R2500 S7 signals were full quieting on the CR-1 with better audio level. Audio is still distorted.
This is strange as the signal quiets the noise, but there is a problem with audio recovery.

Code:
UHF R2500 S1 signals were not heard on CR-1 
    R2500 S3 signals were barely heard on CR-1
    R2500 S5 signals were about 50 percent quieting on the CR-1.
    R2500 S7 signals were full quieting on the CR-1
The audio on UHF sometimes has the same gieger counter clicking noise as on NWS WX, but the audio does not seem distorted.

This confirms my impression that my CR-1 is somewhat deaf on UHF.

73 Eric
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  #242 (permalink)  
Old 03-08-2013, 3:05 PM
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My observation on VHF too, Eric.

Real bad distortion on NWS. Intelligible but not really listenable.
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Old 03-08-2013, 3:44 PM
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NRD-505

Like I said, burn is seen when the power is off. What you're seen are what I'll call 'interesting aftifacts'.
I do see what you're refering too. It looks like it's showing something like 27.000 or something like that.

Big bucket!
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Old 03-08-2013, 3:50 PM
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VHF/UHF issues are being worked on. Firmware fix, of course. CommRadio told me they will be posting /e-mailing a schedule for their software upgrades, listing the topic of the fix (S-Meter, VHF/UHF, etc.) and anticipated release dates of the software for upgrading. Although not always the best at communicating stuff, I do know they are working on resolving issues while tending to production and shipping hardware. Feel free to keep working and reporting the bugs, it all goes into the master TO-DO list.
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Old 03-08-2013, 6:35 PM
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Quote:
Originally Posted by WB2KTG View Post
NRD-505

Like I said, burn is seen when the power is off. What you're seen are what I'll call 'interesting aftifacts'.
I do see what you're refering too. It looks like it's showing something like 27.000 or something like that.

Big bucket!
"Burn In" images are seen on the CRT phosphors when the CRT is off, but the long lasting effect of that process is that, eventually, the image is seen with the CRT on. I am seeing the images with the OLED on. Does the OLED image go away? It hasn't yet.

Maybe "permanent pattern-dependent uneven OLED light output" would be a more appropriate term.

Perhaps a "White Screen" could be in the menu to "wipe" the OLED and level the output.
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  #246 (permalink)  
Old 03-08-2013, 7:29 PM
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After discovering last week that Hurricane Sandy had broken the center insulator of my Big Assed Dipoole back in October, I finally got my new antenna installed. A Bigger Assed Dipole! More copper, higher in the air, resonant frequency ~1.4 MHz! Plenty of signals now.

I did this afternoon what I had tried with marginal success a couple of weeks ago. I fired up the CR-1, my Racal 6790 and my SDR-IQ, I ran competitive tests as follows- Find a signal on the CR-1, listen to it for a while, switch the antenna to the Racal, listen to it there, switch the antenna to the SDR-IQ hooked up to a Panasonic laptop, listen to it there. Mentally compare. Find another signal of interest on the SDR-IQ, listen, listen to same signal on Racal, listen to same signal on CR-1, etc. By rolling through the receivers like this, I got good comparisons of the receivers. I listened throughout the 20M CW band and the 7.5 MHz AM commercial broadcast band. I have concluded that each receiver is capable or receiving what each of the other receivers receive, the sensitivity of all three are basically the same. Strong signal handling was basically the same for all three also. I show in one of the attachments the screen of the SDR-IQ listening to a strong (by American standards) signal. The audio quality of the CR-1 was lesser than either the Racal with a small desktop computer speaker, or the SDR-IQ with the laptop computer's internal speakers. The CR-1 couldn't go as loud, and sounded constrained. Wanting to see if this was a circuit or an internal speaker limitation, I got a KRK ST-8 audiophile studio monitor and hooked it to the CR-1. As the attached silly looking image shows, the speaker is considerably out of scale to the receiver. Well, I could crank the volume on the CR-1 to a LOUD level, and the audio sounded BEAUTIFUL, listening to the music on 7490 KHz! The internal speaker is indeed the weak link in the chain, but then again, for a communications grade 3" internal speaker would you expect more? Fine for it's intended application, but great improvement can be gained with an external speaker (or headphones). Then again, when I got my Drake TR-7 and my ICOM IC-735 many years ago, I got external speakers with them too... Sounds MUCH better for music, voice AND even CW.

Other observations - the AGC on the CR-1 was the best of the three. No user adjustable settings, but for all signals in all modes, it just works right. The Racal is pumping and heaving despite having adjustable time constants, and the SDR-IQ running SpectraVue was only marginally better. Don't know how or what is being done, but it sure works good!
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Old 03-08-2013, 10:34 PM
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"the sensitivity of all three are basically the same."

"the AGC on the CR-1 was the best of the three."

"Strong signal handling was basically the same for all three also"




This is the impression that I had when listening to the recording by Fenu linked above Yesterday. I presume that the AM Broadcast Band (530-1700KHz) performance(on the 1.4 MHz Resonant Wire) is similar using the big antenna to the other radios? It also sounds to me that the Phase noise performance is perhaps quite good, as it sounds clean when tuning across a strong signal, and there does not seem to be a great deal of additional rushing or spraying sound on the sidebands like on some rigs with known phase noise issues.

Thanks for the update

73,

Mike

Last edited by KA0KLQ; 03-08-2013 at 10:38 PM.. Reason: Added frequency range
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  #248 (permalink)  
Old 03-08-2013, 10:48 PM
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"Real bad distortion on NWS. Intelligible but not really listenable."

Here, try one of these: http://radiotimeline.com/ar-radio_shack_cube12-174.jpg I've owned several. Great sound and never any screws missing.
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Last edited by K0OD; 03-08-2013 at 10:51 PM..
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  #249 (permalink)  
Old 03-08-2013, 10:54 PM
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Pi$$ poor on HF though... Like I stated, VHF/UHF will be fixed in firmware.
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  #250 (permalink)  
Old 03-09-2013, 12:34 PM
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Device Characterization is the process of measuring relevant parameters of a piece of hardware or a system under study. This afternoon, for absolutely no good reason at all, I decided to characterize the power requirements of the CR-1. These measurements were taken with a sample size of two receivers, both at DSP1592 revision.

To do this, I provided power to the radios using a Hewlett Packard 6216A variable voltage, current limiting power supply. This power supply provides an analog meter which can be switch selected to display either voltage output or current output.

I powered up the CR-1 and tuned to 10 MHz WWV, a nice strong signal with 'loud' audio output. Cranked it all the way to full volume using the internal speaker. I got the following readings:

Volts mA Power (W)
6 130 .78
9 84 .76
12 65 .78

Both units performed virtually identically. The specification for the receiver says the power consumption at full audio load shall be less than 1 W. These units were ~3/4 W. The specification was met with significant safety factor. Bravo CR-1!

Sorry about the columns not lining up above. I typed it correctly, but RR deleted some spaces on me.
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Old 03-09-2013, 2:56 PM
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Are there expected to be any RF performance differences between the internal battery and external power supply?
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Old 03-09-2013, 3:15 PM
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There better not be any difference! The only time I could imagine a difference would be if someone were to be using an electrically noisy wall-wart or something like that. The radio does have appropriate shielding and is designed to work under normal environmental conditions, but I'm sure a switching supply wall wart could be found which would really make it (or any other radio in the vicinity) sound nasty.
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Old 03-09-2013, 5:36 PM
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Thanks to all for your observations on this new radio. I got brave and ordered one yesterday. Look forward to playing with the CR-1 and seeing how it compares with some of my other gear.
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Old 03-09-2013, 6:11 PM
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Quote:
Originally Posted by ve6brz View Post
Thanks to all for your observations on this new radio. I got brave and ordered one yesterday. Look forward to playing with the CR-1 and seeing how it compares with some of my other gear.
Welcome to the club! Enjoy.
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Old 03-09-2013, 8:54 PM
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Quote:
Originally Posted by WB2KTG View Post
Device Characterization is the process of measuring relevant parameters of a piece of hardware or a system under study. This afternoon, for absolutely no good reason at all, I decided to characterize the power requirements of the CR-1. These measurements were taken with a sample size of two receivers, both at DSP1592 revision.

To do this, I provided power to the radios using a Hewlett Packard 6216A variable voltage, current limiting power supply. This power supply provides an analog meter which can be switch selected to display either voltage output or current output.

I powered up the CR-1 and tuned to 10 MHz WWV, a nice strong signal with 'loud' audio output. Cranked it all the way to full volume using the internal speaker. I got the following readings:

Code:
Volts      mA      Power (W)
  6          130         .78
  9           84         .76
 12           65         .78
Both units performed virtually identically. The specification for the receiver says the power consumption at full audio load shall be less than 1 W. These units were ~3/4 W. The specification was met with significant safety factor. Bravo CR-1!

Sorry about the columns not lining up above. I typed it correctly, but RR deleted some spaces on me.
Hello,

Thanks for the information.

I find the battery life is pretty good. I did not time it, but I used the CR-1 on mostly battery for two days of listening at 5 hours or more per day. I have it recharging now as I am listening to AIR on 11620.

I went out to a local electronics store to get a BNC-F to 1/8 Phone Plug Adapter. I also got some other adapters so I can use the CR-1 with my loop and active antenna.

Years ago I modified a VHF jointed telescoping whip by replacing the whip part with a 72 inch whip from Radio Shack, It has a BNC connector on the end. So now I can use this and other shorter telescoping whips with the 1/8 phone jack antenna input.

The 6 foot whip is overkill, but it worked reasonably good. I need to try it with a counterpoise as well. The signal improved if I touched the ground part of the BNC connector.

While at the store I spotted a 7.2 volt 200 mA Monocrystalline Solar Panel for the Arduino. It has the right plug for the CR-1 so I am going to try it tomorrow. I suspect it can run the radio, but not charge the battery.

73 Eric
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Old 03-09-2013, 11:59 PM
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Hello everyone. I got my CR1 on Friday, and have been playing with it quite a bit. It is interesting how everyone is having varied experiences with the radio, probably depending a lot on location, antenna and expectations. I'll share mine briefly if I may.
* I immediately encountered the freeze problem with my radio, so the update fixed all that. The VHF/UHF is still distorted, but I know they're working on it.
I guess the biggest problem I have is with the AGC shutting the radio down in any congested HF band. For example, 31m in the daytime gives me a +10 to +30 on the S meter throughout the band, whether on a station or not. This lowers the sensitivity of the radio so much that I can't get adequate volume out of it wherever I am tuning in the band. It seems that any signal up to 100khz away will affect the AGC this way. I have tried an external speaker but there just isn't enough audio and it's because the RF gain is effectively all the way down. I am using my 130' flattop antenna fed with ladder line into a 4:1 balun. I have had similar problems with Winradios and the TenTec RX350, but only for signals within 10khz of the tuned frequency. The S meter is allegedly not working right, and I never see less than an S8, but otherwise I think it's telling me what it is seeing in a very broad piece of the band.
Other items: there is no bass in the AM audio. Having a couple of SDR's such as the Perseus and the Andrus MK1.5, I know an SDR has the potential to blow a conventional radio away in AM fidelity. I would like to see more low end.
The squelch only works in FM. Need it for HF and VHF Air.
I don't see why there are separate Amateur and Shortwave bandplans. With a few small exceptions, the two services don't overlap, so I would think just two settings; one for automatic band tuning and one for manual would work better. My AR5000 works like this.
I have this radio on the same antenna as several others through a MiniCircuits passive coupler, and it creates some noise in the other receivers on some bands.
Okay; I've been *****ing because I got that email from the company president yesterday, and he is obviously listening, so I want to put my two cents in for future upgrades.
And here's what I like! It's beautifully made, has a beautiful display and well thought out operation. When the AGC is not shutdown, it receives most everything my other receivers get. Communications sound good and the receiver is quiet. I was very pleased to get the battery option, and it seems to run all day without a problem. I am especially excited that the company is interested in responding to our desires, and willing to extend the return period in good faith. I am looking forward to a long relationship with the CR1.
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Old 03-10-2013, 8:40 AM
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Default Return Policy?

Hi All,
New member & first post.

Does anyone know what the return policy is for the CR-1? I did not see it on the site nor have I seen it here. I have written to the company 2x so far & I have not received even a automated response. I remain very interested, but am put off by the lack of any response. Makes me wonder about issues down the line.

BTW- thanx to all who have posted their CR-1 experience. - 73 Bob
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Old 03-10-2013, 11:19 AM
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Bob-

I am not an employee of CommRadio, but am a radio buddy of the president and chief design engineer Don Moore N0HDX. I am also a beta tester and work as a design / production engineer in the Radio/Computer world as my day job.

I'm sure you will receive a response from someone there shortly. CommRadio is a division of AeroStream Communications, a well established company working primarily in military and other specialized RF product lines. The CR-1 is the embodiment of Don Moore's desire to make a special piece of gear for the amateur and SWL communities. If successful, we may see other products further down the pike. (Did anybody say 'matching transmitter'???).

The company and Don are 100% legitimate and stand behind their product fully. Their standard practice, which I didn't find on their website either, is to offer a 30 day return privilege for any reason whatever. The radio, right now, may be considered by some to be incomplete, since not all of the published specifications have been met. However, the company is rapidly resolving this, and at the same time fixing bugs, and incorporating new features based on user suggestions. Isn't that what we all really want in the long run? My personal recommendation is to support the CR-1 and help it to be the best it can be. Don will be able to do that with all of our help and support!
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Old 03-11-2013, 9:44 AM
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Default Image Issues on the CR-1

Sadly, I'm seeing a problem with images on the CR-1. It will occur on very strong signals (+30 or higher on the S-Meter) and will be 70 Khz higher than the actual Frequency, with the image having a signal level 10 or 20 DB lower, dependent on the strength of signal on the Actual Frequency. Seeing this on the Hi-Z HF antenna input with a Sangean 22 foot reel antenna, so no high end antenna setup. A reboot does not resolve the problem. Powering off the receiver and back on while tuned to the image results in the image still being received after reboot. Hopefully this can be resolved in a firmware update.
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Old 03-11-2013, 11:29 AM
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Default A Sanity Check Please!

I observe the images as reported only on AM signals. Has anybody heard images on either SSB or CW? I want to see if my experiences are the norm.

Thanks All!

Bob
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