LD-1B Part One

I ordered the Lazy Dog Engineering LD-1B SDR receiver on Tuesday and had it in the mailbox on Thursday.  Impressive delivery time I must say.  It came in a small box with a mini cd that included Winrad 1.6.1 and the control software for the LD-1B.

Construction is excellent.  It is in a black aluminum chassis and has an on/off button on the front and two led’s.  The back consists of a usb connector, three 3.5mm connectors and a power connector for a wall wart.

I got out my newer Lenovo Thinkpad that is running Windows 7 64bit and installed Winrad and the LD-1B control software with no problems.  Then I realized the new laptop had no discernible mic jack which is needed to feed the output from the LD-1B to the pc for processing by Winrad.  So I got out a USB dongle sound card that I had and plugged it in.  I turned on the LD-1B and Win7 recognized and configured it right up.  Off we go.

I used it that way for awhile.  It was ok and I started to familiarize myself with Winrad and the controls for the LD-1B.  I found that to bring up the LD-1B control panel you just hit the H key twice.  I played with it this way for a couple of hours, but began to realize that since I was using a really low end sound card, the image rejection wasn’t very good.

So I pulled out a Creative Labs E-MU 0202 USB sound card that I had purchased to work with another SDR I am building.  That’s when the fun began.  I have spent the last two days trying to get the 0202 working.

First the cd for the 0202 doesn’t include Win7 64 bit drivers.  After a search on the internet, I found some beta drivers for it and downloaded them.  Fine, they installed ok and I thought great, here we go.  I would just plug the audio cable from the other sound card in to the input on the back of the 0202.  Doesn’t work.

E-MU 0202After many hours of searching the internet, I finally found information that says you can’t use the 3.5mm jack on the back of the 0202 for input, you only get one channel.  I searched a bit longer and finally found this link: http://www.genesisradio.com.au/G40/11assemblyG40.html that shows you how to make a cable for an 0202 that works for SDR.  After two trips to the local Radio Shack, I get the correct components and the cable is made.

I can now use the LD-1B at a sample rate of 192k with good rejection I believe.  I need to work with the sound card and Winrad more to get the feel of everything.  One thing I have learned is there is a learning curve to SDR.  It’s not the same as firing up the old Icom 746Pro and tunning the dial.  Not harder, just different.

Now I have one problem.  Again with the 0202.  I will go along just fine and then the audio coming from my headset will just stop.  I still see the images on the screen, just no audio out of the head set.  So I am not sure if that is a software issue, or a hardware problem with the 0202.

My first impression of the LD-1B is that it is a well built little unit.  It was pretty much plug and play.  The E-MU 0202, not so much.  So far for me, it has been finicky with documentation in short supply.

More later as I have more time to play with it.  But it does seem like the LD-1B is a good rig to get your feet wet in SDR!

6 comments

  • Patricia

    I’m on the same learning path with the LD-1b and the emu 0202. I am using the 0202 for input and a usb dongle for output. I originally was getting what I thought was ‘crosstalk’ when I used the 202 for input & output. The crosstalk would start as soon as I powered up the SDR and always be a faint signal in the background. It is now gone when I use a separate output device.

    Playing with the 0202’s input level controls and the Winrad’s channel skew calibration is very tricky, but can eliminate the most images.

    I am in the process of hooking an older transceiver with a T/R switch as the transmit section with the SDR as the receiver. Hope to be on 40 meters this weekend.

    73’s

    Patricia – AB4CT
    Montgomery, AL

  • Patricia,

    Thanks for your comments. I am sure others would appreciate it if you could document what you have done so far. Information on setting Winrad up with a E-MU 0202 is kind of sketchy at best. It is surprising considering how many people recommended the sound card.

    Are you using the ASIO 24 bit drivers? If so, how do you seperate the input from the output?

  • Patricia

    Using the ASIO 24 bit drivers? Good question. No I am using the windows 16 bit drivers, since there is no option to use the ASIO drivers for input and something else for output. I might reconnect the speakers to the 0202 this weekend and give it a try — to see if I still get that low level “crosstalk”.

    I had a time getting the E-MU 0202 working in the first place. I am running a Windows XP box – actually did a fresh install then tried installing the drivers. I did it about a half-dozen times before it was right. Actually, it was probably right after the first install. Something is flaky with the drivers and I have to do restart Windows in Safe Mode after every shutdown. If I don’t, about half the time the system will ‘hang’ at startup and never go to the desktop. The other half of the time, it will load to the desktop but not find the 0202 drivers. As soon as the reboot in Safe Mode finishes, I ‘restart’ and Windows restarts properly with the 0202 available.

    Since I only use this machine for WINRAD, this is not too much of a problem. I try to do a restart every Saturday morning – just to clean things up a bit.

    Using the EMU 0202 with the LD-1b… Don’t use the mini 1/8″ connector marked L-mic, you need to have two separate cables (use a 1/8″ splitter and two 1/8″ mini connectors – mono cables) On the EMU-0202 end you will need a couple of 1/8″ male to 1/4″ adapters. You can find them at Radio Shack. One goes in the 1/4′ jack marked L input and the other goes in the center of the special microphone connector. Yes, if you look closely, there is a 1/4 hole there for the right input.

    Deciding which cable goes into which input on the back is a tossup. When you start WINRAD and you discover things are not exactly on frequency, you can switch them at the back of the 0202 (there is actually a menu that lets you switch them also)

    The two controls for left and right input (on the front) are fairly sensitive. Start with the left control almost at minimum and the right control about at 1. There actually isn’t a “1” marked, but you know what I mean. As you begin using the LD-1b with WINRAD, you will find that you need to balance the two inputs in order to reduce images, but that is for later. Plug the cable from the 0202 into your speakers and you are ready.

    Now with the sound board installed and running – you know this because the little app on your desktop marked “EMU-0202” or some such thing can be clicked and shows you that the device is set for 192 Kz or 96…and of course you have installed the WINRAD software and the LD-1b dll’s. You are ready to give it a try.

    Start WINRAD & go to “Select Sound Card” to select the input and output sound cards. Click OK> I don’t remember if you need to restart WINRAD or not???

    The software remembers the things you select via menus so that when you start winrad, it immediately loads the LD-1b LO app. Move the slider to the frequency you select. I chose 7.251, which is one of the choices and click Start. If all is well – and you have an antenna that will receive 40 meters, the waterfall display will begin and noise will come from your speakers. I like 7.251 because it is the frequency of the South Coast Amateur Radio Net (SOUTHCAR) from 8:00 – noon EST. Each morning I start here and it confirms that my receiver is right on frequency.

    When I first used WINRAD, I could only receive on 40 meters (that is the only antenna I have right now) and ssb signals were all USB. Funny, I thought 160 – 40 (except for 5.1 mhz) was LSB… (it is!)

    I had my cables backwards. Switchin them and I found WWV right on the money.

    Now you are up and running. In the Show Options menu, check to see if you are using the WWME drivers or the ASIO drivers. Give the ASIO Drivers a try. I hear that they give you a lower noise level.

    Learn to spot images. Once you know what they look & sound like, try adjusting the input levels on the 0202 and moving the sliders on the channel skew calibration. I have found the most change when I click on the 1 to 4 sample delay right or left.

    If you have problems with low background noises that don’t change as you move across the band or audio that drops out completely, you might try the built-in sound card and a USB sound dongle. That solved it for me.

    I love the graphic display! Sometimes, I can see a half dozen sideband signals across almost 100 kc of spectrum and even more code signals. Hope this helps someone get started.

    Patricia – AB4CT
    Montgomery, AL

  • Patricia,

    Awesome information. I had been looking for a write up like that for sometime. Come back often and let me know how it is going.

    Allen – KBØASQ

  • Patricia

    A short addition about using the E-MU 0202 sound box with the LD-1B SDR…

    I had a few minutes last night so I connected my speakers (cheap – cheap – cheap) to the 1/8″ stereo connector on the read of the 0202. (I also have a USB Logitech headset that I use when the radio bothers the OM) With both the input and output connectors using the 0202, I went into options and selected the ASIO 24 bit drivers.

    The noise immediately decreased. I listened to 40 meters for a while then decided to continue learning how to reduce the various images. I had become fairly proficient using the front controls on the 0202 along with the Channel Skew Calibration setting. I went into the Calibration settings and clicked on the right delay button – immediately the sound stopped! The waterfall display continued and even showed that as I made adjustments I could increase & decrease the image strengths.

    I changed back to the 16 bit drivers – selected the Logitech headset and the sound came back. I’m not certain if when I again selected the 24 bit drivers the sound stayed or I had to exit and restart. I did this a couple of times to verify that the sound dropping was a real problem.

    On the way to work, I realized that a work-around might be to start up with the 16 bit drivers, select the frequency range I wanted to work – reduce images THEN switch to the ASIO drivers. I’ll try it tonight.

    Patricia – AB4CT
    Montgomery, AL

  • Patricia

    A few further comments about my experiences with the LD-1B Software Defined Radio from Lazy Dog Engineering:

    (1) I found an MFJ preselector on eBay and it performs great. Of course it doesn’t track automatically, but I had a preselector years ago and it really brings the weak signals out of the noise. It makes a very faint ssb signal readable.

    (2) More on images… When you look at the waterfall display at a SSB signal, it is not difficult to discern if it is USB or LSB. The USB signal is shaped like a capital “D”, with a very sharp dropoff on the left side and the modulation is on the right. Likewise a LSB signal is shaped like a capital “D” turned backwards with the sharp dropoff on the right side. This is important because if you are on 160, 80 or 40 meters, almost all of the sideband signals will be LSB. If you see a sideband signal that won’t tune in with the LSB button but will tune in with the USB button, then it PROBABLY is an image. Take a peek at the other side of the display to see if there is an opposite signal that you CAN hear properly with LSB. The one you can hear with LSB is the signal and the other is an image. (just backwards on all other bands that allow voice) You can probably reduce the image. This is important, if you are building a rig and need to know the frequency of the signal so you can tune your transmitter.

    (3) More on antennas… I have been using an inverted V 40 meter antenna (hanging in a terrible forest of trees!) since I first received the LD-1B. A few weekends past, a friend, who put up the 40 meter V, climbed and added an 80 meter V. Prior to the new 80 meter V, I had good local (southeast US) reception on 40 M and the occasional 80 meter signal. All other bands were almost devoid of signals. Now, I get great reception on 80. Additionally, I found 20 meters active a week or so ago and 10 meters was booming. Nothing on 15 – guess I’ll have to add a 15 meter V in a couple of weeks.

    I hope to be on 40 meters sideband this weekend. I have tuned the antenna on both 40 & 80 and have a T/R switch that seems to function as required. Using a separate receiver and transmitter is a bit klugy, but hopefully, the T/R switch should keep me from burning out the preselector and the receiver. If you remember old photos from the 1920’s and 30’s ham stations – three or four wood boards with various tubes, capacitors and coils and a big knife switch running to various lengths of wire, well my station doesn’t look that terrible, but it’s not a FLEX 5000 either!

    Patricia AB4CT
    Montgomery, Alabama

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