New SDR CommRadio CR-1

[nanZor]

PAR VHF-FM trap restores airband

Went back to the club station to give airband monitoring a bit more time.

With an S10 reading and no signals seemingly present, I knew something was up. The PAR vhf-fm notch fixed that, and the CR1a sounds just fine on airband now with about an S3 to S4 reading with no signals present.

The AOR airband passband filter worked too, but I'm going to leave that for HT duty, and stick to PAR for my filtering needs for the CR1a. I couldn't switch them fast enough to make a precise judgement, but my nod goes to the PAR.

At home I don't really need the filters, but will leave the trap attached anyway for good measure.

 

[nanZor]

Can't duplicate QST review with distorted audio

One of my major attractions to the CR1a is the cleanliness of the audio. Even though I'd like to see some tweaks / feature improvements, I find the audio chain superb - especially for teeny smc componentry.

I tried to force the issue to see if I could come up with low level distortion, and the closest I could come was purposely using the wrong jack with the wrong impedance.

The headphone jack is only rated at 40 milliwatts into a 16 ohm load. The speaker output is rated at 800 milliwatts into an 8 ohm load.

So generally I use the jacks as they were designed - that is I don't put a an 8 ohm speaker into the headphone jack! I'm not saying QST was doing this - I don't know without details, but doing that is similar to what they were reporting and I've done it by mistake many times with other gear.

My own testing with the headphone jack is that like most other amps that use small componentry, impedance matching is important - at the very least going no lower than what it is rated for for best results. So far, the Yaesu YH77sta and Radiosport RS20 headsets are my favorite, and have impedances higher than 8 ohms to provide a nice load to the amps, instead of a near-short. Those along with the Palstar speaker show no signs of low level distortion - at least to ME since everything is subjective.

Note that all of my testing is also SOLELY from battery, internal or external, to make sure I'm not inadvertently listening to ground-loops or other junk. The rig is also floating on batteries only when testing antennas as well - just to make sure I'm not introducing anything funky from a wall-wart.

 

[nanZor]

Survives multiple ESD strikes

The last few days have been windy and dry. I also have cheap synthetic carpeting, sneakers, cotton clothing, a floating CR1a, and a glass tabletop.

Merely standing up from the shack chair and touching a rig can take it out - like I did with an Icom 718's vfo encoder a few years back.

Did the same today by accident with the CR1a with a full four-finger zap that a wizard would be proud of. It survived.

Later, it happened again, but this time it all went into the headphone jack. Lost audio completely, could no longer tune, and could no longer adjust volume. It wouldn't even shut down completely normally. OUCH.

I did a forced shutdown by holding the power button down longer than usual, and it all came back fully operational.

Thanks Don! I guess you did try and fight ESD.

 

[corbintechboy]

The last few days have been windy and dry. I also have cheap synthetic carpeting, sneakers, cotton clothing, a floating CR1a, and a glass tabletop.

Merely standing up from the shack chair and touching a rig can take it out - like I did with an Icom 718's vfo encoder a few years back.

Did the same today by accident with the CR1a with a full four-finger zap that a wizard would be proud of. It survived.

Later, it happened again, but this time it all went into the headphone jack. Lost audio completely, could no longer tune, and could no longer adjust volume. It wouldn't even shut down completely normally. OUCH.

I did a forced shutdown by holding the power button down longer than usual, and it all came back fully operational.

Thanks Don! I guess you did try and fight ESD.

Don was very proud of the fact that the radio had many layers of static protection.

Glad to know it works. Good job Don (I know you read these forums, take care of yourself).

I will probably never get to test it. I keep the humidity in here pretty much level with a humidifier. I can't stand shocking everything I touch. lol

 

[nanZor]

160m is back with MFJ 1046 preselector!

Got the passive preselector in today, and at night when the 40m broadcasters are rolling in, it wiped out 160 in many places. Why is there a Russian guy talking in the cw dx window?

That was the most noticeable problem it fixed. By surprise though, it also fixed the random tuning-pops in that band!

For the most part I plan to leave it bypassed unless doing 160, but when I get another chance I'll see if the preselector helps do away with some random tuning pops I get on the higher bands. We'll see.

Not being able to disable / tame the agc on the CR1a makes tuning external circuits like transmatches and adjustable loading coils tedious. Fortunately, the dial calibration on the MFJ preselector is close enough. A transmatch is a different story, so you'll need another radio, or perhaps an antenna analyzer since you won't know by tuning manually until you are right on top of your target.

Still, not complaining as I just pulled about 22 hours from an 8-pack of Powerex 2500 AA rechargeables with it. Again, blown away by what only 75 milliamps (when internal battery is fully charged) is accomplishing.

 

[WB2KTG]

CR-1a Power Supply Functionality

Hertzian-

"about 22 hours from an 8-pack of Powerex 2500 AA rechargeables" Were you using all 8 batteries in series to give the radio 12V? If so, I believe you would get almost the same 22 hours using 4 batteries in series to give yourself 6V, then another almost 22 hours with the second set of 4 batteries. I'm pretty sure the internal regulator in the CR-1a just drops and regulates the internal voltage to provide the ~5V necessary for proper function. I believe anything over the 5V is dissipated as heat. If I'm wrong about your using all 8 batteries in series, nevermind...

 

[nanZor]

I was running an 8-cell holder in series. Wanted to keep the voltage up, so the current stays low. The watts drawn by the CR1a stays the same, so it just follows the PIE (P/I*E) chart.

I wanted to make sure that I could fully drain the NiMH batteries without damage - and that means stopping at about no lower than 1v per cell. So at 8v, I pulled it and it was starting to nosedive in voltage anyway. Still above the 6v lower voltage limit on the dc input.

The nimh cells are pampered with a Maha/Powerex 8-cell charger.

Other battery news: about 90 minutes from an Imedion 8.6v rechargeable before it started to nosedive at 7.5v.

Aluminum-Air diy batteries: FAIL. 1A at 1V seems nice but only when unloaded. The CR1a load, even as small as it is, caused a major voltage drop. And after an hour or so, the salt-water electrolyte and oxidation ate through the kitchen foil and caused a mess underneath and on the table. Fun, but messy.

Now operating and charging the CR1a from a NOCO Genius GB30 lithium jumpstarter pack via the usb port just for kicks.

The CR1a is a lot of fun for battery geeks like me, that's for sure.

 

[nanZor]

My camping / hiking setup

Trying to keep components / wiring to a minimum for a backpack, the NOCO lithium jumpstarter turns out to be ideal.

Anker 14w folding panel - charges either the cr1a or Noco directly.
NOCO GB30 lithium jumpstarter. Clamps left in vehicle.

Took the CR1a down to the point where the battery status icon has an "X" inside, and didn't feel like discharging it to the point where the battery's own protective circuit activated.

Took about 4.5 hours for the NOCO jumpstarter to charge the CR1a fully via USB, and left the noco with about 50% left.

Noco obviously jumps a dead truck to get me off the mountain, but will also charge and operate the CR1a via usb, and has about 24wh capacity. The dimmable leds tested out great in the backyard tent for area lighting. I'm going to time it out from a fully-charged internal battery just to know for sure.

The best news is that I detect NO QRM from the dc-dc converters during charge or discharge to my portable antennas only 5 feet away from HF to UHF, unless I place the unit directly on top of my coax.

Despite this, I kind of wish the cr1a had a programmable APO or automatic power-off timer.

 

[n0sa]

What External Speaker do You Use for CR-1

I have a CR-1a and I am using an RS Optimus Pro.
It works and looks good but is a bit on the bassy side.
I was wondering if anyone has good luck with maybe a bit smaller
speaker that looks and sounds good with the CR-1.
It would be nice if CommRadio made a matching speaker that
is the same size as the CR-1. I like to set my CR-1 on top
of my Optimus speaker.
So, what have you had good luck with.
I just got a brand new CR-1a and I am having fun with it with
a home brew wideband active loop.
Larry
n0sa

 

[n0sa]

Using the CR-1a with a transmitter?

Has anyone tried using the CR-1a with a transmitter for ham radio use?
I like to experiment with CW transmitters and if there was an easy way to add
a mute function to the CR-1a it would make a nice CW transmitter-receiver.
Larry
n0sa

 

[nanZor]

I like to set my CR-1 on top of my Optimus speaker.

Quite a lot of options here. While I haven't personally listened to them, perhaps the West Mountain Radio COMspkr would be worth looking at. Sit one of them on the desk sideways, and put the CR1a on top. The RF filtering would come in handy since you are also thinking of using it with a transmitter / mute control. Of course use the front panel line out jacks, and not the rear speaker jack.

My favorite passive solution that sounds great (at least to me), and looks like a good mate is the Palstar SP30b (black wood).

 

[EricCottrell]

Hello,

My CR-1 had tuning problems for months. The frequency would jump up and down and I really have to turn the tuning knob slowly for the radio to somewhat tune.

Tonight I decided to look at it on the scope and it turns out the rotary encoder is noisy. No wonder I had problems. I guess I need to ship it off to get it fixed.

73 Eric

 

[EricCottrell]

Hello,

I decided to try spraying contact cleaner on the noisy encoder carefully and hope it seeped into the cracks. It worked! All the noise went away and now the CR-1 tunes great!

73 Eric

 

[EricCottrell]

Hello,

The encoder problem returned this morning, so the cleaner was only a temporary fix.

73 Eric

 

[nanZor]

You've only done half the job.

Earlier, I put my vfo through a prolonged torture test to the point where I had a similar situation. The encoder was fine, it was just that it was *physically* jumping with a totally dry shaft. I had a similar issue with an older Yaesu FT-840 vfo shaft with super tight tolerance.

Like you, I used contact cleaner on my CR1a, DeOxit which of course cleaned it, BUT the skipping shortly returned as the shaft has no lubricant.

Now that the shaft is clean, I used 3-in-1 multipurpose oil (red white black bottle) *sparingly* - like 3 drops max and let it settle.

No problems after 3 months, and so far no gunking up like wd40 tends to do eventually. VFO is nice and smooth, although snug like it was when it was brand new.

 

[EricCottrell]

You've only done half the job.

Earlier, I put my vfo through a prolonged torture test to the point where I had a similar situation. The encoder was fine, it was just that it was *physically* jumping with a totally dry shaft. I had a similar issue with an older Yaesu FT-840 vfo shaft with super tight tolerance.

Like you, I used contact cleaner on my CR1a, DeOxit which of course cleaned it, BUT the skipping shortly returned as the shaft has no lubricant.

Now that the shaft is clean, I used 3-in-1 multipurpose oil (red white black bottle) *sparingly* - like 3 drops max and let it settle.

No problems after 3 months, and so far no gunking up like wd40 tends to do eventually. VFO is nice and smooth, although snug like it was when it was brand new.

Hello,

Thanks, I will try a little light machine oil.

73 Eric

 

[SigIntel8600]

CR-1a

I received a CR-1a for Christmas. So far the receiver is performing as expected. Does anyone know if there are any updates in the pipeline? Is anyone aware of any third party software development? Thanks.

 

[KB2RSK]

After reading about a year and a half worth of posted comments of the CR-1 and the CR-1A I have decided to take the plunge and put my order in. Should be receiving it with in the next few days.
Hope to be able to post my personal evaluation. I have been an amateur OPR since the age of 14, and now at 61 plus. I have had hands on experience with some old boat anchors and new SDR related transceivers. This should be another one of those interesting adventures. 73 and hope to comment soon.

 

[APSN556]

I Highly suggest owners of this radio join the yahoo group at https://groups.yahoo.com/neo/groups/CommRadio/info

 

[KB2RSK]

ok
Thank You